Heidi E Brown

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Books

• Oren, E., & Brown, H. E. (2023). Infectious disease epidemiology: An introduction. Springer Publishing Company.
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  Infectious Disease Epidemiology: An Introduction is a foundational textbook for public health and related health science degrees. It provides a comprehensive public health strategy for understanding and managing the spread of infectious diseases. This unique book offers an integrated approach that covers the important methods underlying the discipline of infectious disease epidemiology, while also illustrating key social and environmental factors critical for understanding disease spread and its effect on population health. The book is divided into four parts that cover the entire scope of infectious disease origin, spread, and management. It breaks down factors leading to disease emergence and modes of transmission, the social, behavioral, cultural, and environmental dimensions that contribute to communicable spread and severity, as well as the tools used for disease detection, surveillance, control, and eradication. It discusses the latest knowledge and technologies in the field-including specific coverage on the role of big data and digital disease detection, the impact and challenges of vaccines, and much more. Core epidemiologic principles are explored through rich real-world examples, utilizing a combination of case studies, popular media examples, and didactic exercises. Each chapter has an engaging narrative and includes key terms and definitions, insightful vignettes, visually compelling illustrations, thought questions, and discussion questions to foster critical thinking and spark further investigation. Infectious Disease Epidemiology: An Introduction is an essential resource for students of public health and other health professionals in developing a nuanced and comprehensive understanding of this growing and dynamic field. Key Features: Provides students with an integrated approach illustrating important epidemiologic methods and tools in the context of current and historic real-world examples Uses multidisciplinary approaches to contextualize broader socio-behavioral factors and disparities in infectious disease Illustrates how novel methodological and technological advances support progress in infectious disease epidemiology Poses engaging discussion questions in each chapter that help guide in-class discussions and group work Purchase includes digital access for use on most mobile devices or computers, and qualified instructors also have access to a full suite of instructor resources.

Chapters

• Smith, E. M., Lashway, S. G., Laukaitis, C. M., Brown, H. E., Lynch, C. F., & Dennis, L. K. (2022). Cancer. In Maxcy-Rosenau-Last Public Health and Preventive Medicine. New York: McGraw-Hill Medical.
• Garfin, G. M., Garfin, G. M., Gonzalez, P., Breshears, D. D., Brooks, K., Brown, H. E., Elias, E., Gunasekara, A., Huntly, N., Maldonado, J. K., Mantua, N. J., Margolis, H. G., Mcafee, S., Middleton, B. R., Udall, B., Huntly, N. J., Middleton, B. R., & Maldonado, J. K. (2018). Chapter 25 : Southwest. Impacts, Risks, and Adaptation in the United States: The Fourth National Climate Assessment, Volume II. In The Fourth National Climate Assessment, Volume II. U.S. Global Change Research Program. doi:10.7930/NCA4.2018.CH25
• Udall, B. H., Middleton, B. R., McAfee, S., Margolis, H. G., Mantua, N. J., Maldonado, J. K., Huntly, N., Gunasekara, A., Elias, E. H., Brooks, K. M., Brown, H. E., Breshears, D. D., Garfin, G. M., & Gonzalez, P. (2018). Southwest. In Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II(pp 1101–1184). Washington, DC: U.S. Global Change Research Program. doi:doi: 10.7930/NCA4.2018.CH25
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  Chapter 25 in the Fourth National Climate Assessment
• Ernst, K. C., Morin, C., & Brown, H. E. (2015). Extreme Weather Events and Vector-borne Diseases. In Public Health in Natural Disasters: Nutrition, Food, Remediation and Preparation. Wageningen Academic Publishers.
• Brown, H. E., Comrie, A. C., Tamerius, J., Khan, M., Tabor, J. A., & Galgiani, J. N. (2014). Climate, wind storms, and the risk of valley fever (coccidioidomycosis). In The Influence of Global Environmental Change on Infectious Disease Dynamics(pp Chapter A12). Washington, D.C.: The National Academies Press.
• Brown, H. E., Comrie, A. C., Drechsler, D., Barker, C. M., Basu, R., Brown, T., Gershunov, A., Reisen, W. K., & Ruddell, D. (2013). Health Effects of Climate Change in the Southwest. In Assessment of Climate Change in the Southwest United States: a Technical Report Prepared for the U.S. National Climate Assessment.(pp 312-339). Southwest Climate Alliance.
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  Review Editor: English, P. Health Effects of Climate Change in the Southwest. Chapter 15, in: Assessment of Climate Change in the Southwest United States: a Technical Report Prepared for the U.S. National Climate Assessment. A report by the Southwest Climate Alliance [Garfin, G., Jardine, A., Merideth, R., Black, M., and Overpeck, J. (eds.)]. 2013, Tucson, AZ: Southwest Climate Alliance.
• Liverman, D., Moser, S. C., Weiland, P. S., Dilling, L., Boykoff, M. T., Brown, H. E., Gordon, E. S., Greene, C., Holthaus, E., Niemeier, D. A., & others, . (2013). Climate choices for a sustainable Southwest. In Assessment of Climate Change in the Southwest United States(pp 405--435). Island Press/Center for Resource Economics.

Journals/Publications

• Ahn, M. W., Keith, L., & Brown, H. E. (2025).

  Rural heat health disparities: Evidence from the U.S. National Emergency Medical Services Information System (NEMSIS)

  . The Journal of Climate Change and Health, 22(2025), 100432. doi:10.1016/j.joclim.2025.100432
• Ahn, M., Keith, L., & Brown, H. E. (2025). Rural heat health disparities: Evidence from the U.S. National Emergency Medical Services Information System (NEMSIS). Journal of Climate Change and Health, 22(Issue). doi:10.1016/j.joclim.2025.100432
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  Background: Increasing average temperatures and extreme heat events due to climate change have adverse effects on human health. Previous studies focus on the heat impacts in urban areas due to the focus on the greater population and urban heat island effect, but this tendency results in the effect of heat on rural health being overlooked. Methods: Using the National Emergency Medical Services Information System (NEMSIS) data from 2021 to 2023, this study compares heat-related illness (HRI) in urban and rural areas of the U.S. Results: We found the odds of EMS events in an urban area resulting with a positive outcome for the patient was 1.24 times that of EMS events in rural areas. This urban-rural disparity was not equal across regions with the odds of EMS events to rural areas of the Western U.S. resulting with a positive outcome for the patient was 54 % less than that for urban areas. Conclusion: This critical evidence of a rural-urban heat health disparity calls attention to the impact of climate change-fueled heat impacts on health in communities of all sizes, and a need for more rural heat resilience research to inform practice.
• Austhof, E., Brown, H. E., Ferguson, D., & Jernberg, J. B. (2025).

  What burns in a wildfire influences cardiovascular health outcomes: A systematic review and meta-analysis

  . Ecotoxicology and environmental safety, 303, 118751.
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  The goal of this systematic review and meta-analysis is to understand cardiovascular health outcomes following wildfire and determine if fuel type clarifies variation in the association. The systematic review included English, peer-reviewed, primary data analysis studies that explored wildfire exposures with associated cardiovascular morbidity or mortality health outcomes published up to October 17, 2023 and identified through five databases (PROSPERO Protocol #CRD42024589994). We extracted article details, fire exposure metrics, cardiovascular health outcome metrics, study design, measures of association (risk ratio [RRs], incidence rate ratios [IRRs] and 95 % confidence intervals [CIs]), covariates, confounding factors, and stratified analyses from each article. Risk of bias was assessed using the Cochrane tool. Random effects meta-analyses, stratified by natural or structure/peat fuel types were conducted. Pooled estimates for all cardiovascular disease (pRR:1.04, 95 % CI: 1.01, 1.07), dysrhythmia (pRR:1.05, 95 % CI: 1.01, 1.09), and hypertensive disease (pRR:1.04, 95 % CI: 1.01, 1.07) were significantly associated with fire exposure. There were significant between group differences between wildfires with structure/peat sources compared to natural sources for all cardiovascular ED visits (RR structure/peat: 1.08, 95 % CI: 1.03, 1.12; RR natural: 1.03, 95 % CI: 1.00, 1.05) and dysrhythmia ED visits (RR structure/peat: 1.10, 95 % CI: 1.04, 1.09; RR natural: 1.02, 95 % CI: 0.98, 1.06). When exploring pooled estimates of risk for cardiovascular health, we find higher estimates and narrower CIs for structure/peat sources compared to natural wildfires with largely null estimates and wider CIs. Future detailed and consistent information about wildfire fuel types will help to inform better wildfire response.
• Austhof, E., Brown, H. E., Ferguson, D., & Jernberg, J. B. (2025). What burns in a wildfire influences cardiovascular health outcomes: A systematic review and meta-analysis. Ecotoxicology and Environmental Safety, 303. doi:10.1016/j.ecoenv.2025.118751
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  The goal of this systematic review and meta-analysis is to understand cardiovascular health outcomes following wildfire and determine if fuel type clarifies variation in the association. The systematic review included English, peer-reviewed, primary data analysis studies that explored wildfire exposures with associated cardiovascular morbidity or mortality health outcomes published up to October 17, 2023 and identified through five databases (PROSPERO Protocol #CRD42024589994). We extracted article details, fire exposure metrics, cardiovascular health outcome metrics, study design, measures of association (risk ratio [RRs], incidence rate ratios [IRRs] and 95 % confidence intervals [CIs]), covariates, confounding factors, and stratified analyses from each article. Risk of bias was assessed using the Cochrane tool. Random effects meta-analyses, stratified by natural or structure/peat fuel types were conducted. Pooled estimates for all cardiovascular disease (pRR:1.04, 95 % CI: 1.01, 1.07), dysrhythmia (pRR:1.05, 95 % CI: 1.01, 1.09), and hypertensive disease (pRR:1.04, 95 % CI: 1.01, 1.07) were significantly associated with fire exposure. There were significant between group differences between wildfires with structure/peat sources compared to natural sources for all cardiovascular ED visits (RR structure/peat: 1.08, 95 % CI: 1.03, 1.12; RR natural: 1.03, 95 % CI: 1.00, 1.05) and dysrhythmia ED visits (RR structure/peat: 1.10, 95 % CI: 1.04, 1.09; RR natural: 1.02, 95 % CI: 0.98, 1.06). When exploring pooled estimates of risk for cardiovascular health, we find higher estimates and narrower CIs for structure/peat sources compared to natural wildfires with largely null estimates and wider CIs. Future detailed and consistent information about wildfire fuel types will help to inform better wildfire response.
• Begay, R. L., Brown, H. E., Sanderson, P. R., & Harris, R. B. (2025).

  Diné traditional medicine use and wellbeing among navajo adults during the COVID-19 pandemic: A cross-sectional study

  . PloS One, 20(12), e0337427.
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  To assess perceptions of the impact of the COVID-19 pandemic on access, utilization, and perceived quality of Diné traditional medicine and healing (DTM) and psychosocial wellbeing among members of the Navajo Nation.
• Brown, H. E., Boyd, K., Howard, M., Seaton, D., Begay, R. L., Sanderson, P. R., & Harris, R. B. (2025).

  Care-Seeking Action after Helicobacter pylori Testing among a High-Risk Indigenous Population: A Cross-Sectional Study Follow-up

  . The American journal of tropical medicine and hygiene, 112(3), 518-524.
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  Helicobacter pylori is one of the most common infectious agents linked to any malignancy. Recent studies report higher H. pylori prevalence and gastric cancer incidence rates in the Navajo Nation than in general U.S. populations. Little is known about barriers to care and treatment. Participants of the 2022 Navajo Healthy Stomach Project who had a positive urea breath test for H. pylori were contacted after 6 months to assess health care services sought, treatment received, and barriers to accessing care. Descriptive statistics identified perceived barriers to care seeking and treatment. Of individuals consented to recontact, 83 were surveyed (69.8% response rate). Just over half (52.8%) reported following up with an allopathic clinician. The most common reasons for not seeking care were lack of time (37.5%) and forgetting (25.0%). Care seeking was more common among those who felt that H. pylori was linked to their gastrointestinal symptoms (P = 0.03) or those less concerned about adverse effects of antibiotics (P = 0.07). Community engagement throughout the research process and intentionally sharing research finding with communities may be strategies to reduce barriers to care seeking after a positive H. pylori infection diagnosis.
• Brown, H. E., Boyd, K., Howard, M., Seaton, D., Begay, R. L., Sanderson, P. R., & Harris, R. B. (2025). Care-Seeking Action after Helicobacter pylori Testing among a High-Risk Indigenous Population: A Cross-Sectional Study Follow-up. American Journal of Tropical Medicine and Hygiene, 112(Issue 3). doi:10.4269/ajtmh.24-0393
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  Helicobacter pylori is one of the most common infectious agents linked to any malignancy. Recent studies report higher H. pylori prevalence and gastric cancer incidence rates in the Navajo Nation than in general U.S. populations. Little is known about barriers to care and treatment. Participants of the 2022 Navajo Healthy Stomach Project who had a positive urea breath test for H. pylori were contacted after 6 months to assess health care services sought, treatment received, and barriers to accessing care. Descriptive statistics identified perceived barriers to care seeking and treatment. Of individuals consented to recontact, 83 were surveyed (69.8% response rate). Just over half (52.8%) reported following up with an allopathic clinician. The most common reasons for not seeking care were lack of time (37.5%) and forgetting (25.0%). Care seeking was more common among those who felt that H. pylori was linked to their gastrointestinal symptoms (P 5 0.03) or those less concerned about adverse effects of antibiotics (P 5 0.07). Community engagement throughout the research process and intentionally sharing research finding with communities may be strategies to reduce barriers to care seeking after a positive H. pylori infection diagnosis.
• Brown, H. E., Pauli, L., Dholakia, R., Gunderson, J., Jernberg, J., Sanderson, P. R., Harris, R. B., & Monroy, F. P. (2025).

  Diagnostic Testing Accuracy in a High-Prevalence Native American Population of Northern Arizona

  . Microorganisms, 13(8).
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  ( is a common gastric pathogen and a leading cause of non-cardia gastric cancers. Known determinants can affect the diagnostic accuracy of invasive clinical methods for diagnosis. The objective of this study was to determine the diagnostic accuracy of the CLOtest, a rapid urease test, and the histopathologic examination compared with polymerase chain reaction (PCR) in esophagogastroduodenoscopy patients from a population with high prevalence and other risk factors that may influence diagnostic accuracy. From 2018 to 2022, patients were recruited from a medical care center serving the southwestern Navajo Nation. Summary statistics were calculated using PCR as the comparator to the CLOtest and histopathologic examination. Among the 466 study participants, 27.1% (95% CI 22.9, 31.7%) tested positive for using PCR to detect pathogen DNA. Sensitivity was lowest for the CLOtest (57.0%; 95% CI 45.8, 67.6) and highest for the combination the CLOtest and histopathology (72.2%; 95% CI 62.8, 80.4). Patient history of infection or possible GI bleeding influenced sensitivity by over 5%. In high prevalence areas, emphasis should be placed on ensuring adequate treatment of suspected positive infections as false-positive results were rare. Including a more sensitive test might reduce the number of individuals falsely classified as negative.
• Brown, H. E., Pauli, L., Dholakia, R., Gunderson, J., Jernberg, J., Sanderson, P. R., Harris, R. B., & Monroy, F. P. (2025). Helicobacter pylori Diagnostic Testing Accuracy in a High-Prevalence Native American Population of Northern Arizona. Microorganisms, 13(Issue 8). doi:10.3390/microorganisms13081920
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  Helicobacter pylori (H. pylori) is a common gastric pathogen and a leading cause of non-cardia gastric cancers. Known determinants can affect the diagnostic accuracy of invasive clinical methods for H. pylori diagnosis. The objective of this study was to determine the diagnostic accuracy of the CLOtest, a rapid urease test, and the histopathologic examination compared with polymerase chain reaction (PCR) in esophagogastroduodenoscopy patients from a population with high prevalence and other risk factors that may influence diagnostic accuracy. From 2018 to 2022, patients were recruited from a medical care center serving the southwestern Navajo Nation. Summary statistics were calculated using PCR as the comparator to the CLOtest and histopathologic examination. Among the 466 study participants, 27.1% (95% CI 22.9, 31.7%) tested positive for H. pylori using PCR to detect pathogen DNA. Sensitivity was lowest for the CLOtest (57.0%; 95% CI 45.8, 67.6) and highest for the combination the CLOtest and histopathology (72.2%; 95% CI 62.8, 80.4). Patient history of infection or possible GI bleeding influenced sensitivity by over 5%. In high H. pylori prevalence areas, emphasis should be placed on ensuring adequate treatment of suspected positive infections as false-positive results were rare. Including a more sensitive test might reduce the number of individuals falsely classified as H. pylori negative.
• Brown, H. E., Wrench, E., Wolfe, K., Moore, T. C., Tangena, J. A., & Sedda, L. (2025). Collaborative engagement with vector control stakeholders is key to enhance the utility of vector-borne disease models. Parasites and Vectors, 18(Issue 1). doi:10.1186/s13071-025-06751-w
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  Background: Despite the growing complexity, computational power, and mapping capacity incorporated into vector-borne disease models, they still do not fully elucidate the role of environmental, demographic, socioeconomic, or other drivers, and rarely directly inform vector control efforts. To understand how we can improve the utility of vector-borne disease models for vector control activities, we interviewed vector control agents from the United States (USA) and the European Union. Methods: Between July and December 2023, in-depth interviews were held using a geographically targeted convenience sample with 26 individuals from organizations involved in vector control operations: 12 in the USA and 14 in the EU. We used both deductive and inductive coding of transcribed interviews to identify themes with the goal of understanding barriers to model use and uptake. Results: Despite the recognition that models could be useful, few interviewees reported that models informed surveillance and control activities, citing a mismatch in spatial and temporal scale between model outputs and operational decisions or a general lack of accessibility. Interviewees reported relying on experienced field experts and legacy protocols. Despite these critiques, there is belief that models can support operational decision-making. Conclusions: The disconnect between models and users can be improved by allowing time and resources to build collaborative relationships, by acknowledging the knowledge all members bring, and by ensuring clear communication and mutual respect. Modelers must shift their focus by aligning vector-borne disease models with operational needs.
• Moore, T. C., Tang, X., & Brown, H. E. (2025).

  Assessing the Relationship Between Entomological Surveillance Indices and West Nile Virus Transmission, United States: Systematic Review

  . Vector borne and Zoonotic Diseases (Larchmont, N.Y.), 25(5), 317-328.
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  Entomological surveillance indices are used to estimate the risk of West Nile virus (WNV; family Flaviviridae, genus ) transmission. To determine when and where to initiate mosquito control activities, integrated vector management programs establish action thresholds based on entomological surveillance indices. However, the application of entomological surveillance indices needs further investigation relative to the human risk of WNV infection. Herein, we examine the evidence from studies that investigated the quantitative relationship between entomological surveillance indices and human WNV cases using systematic review methods. Across three databases, 5378 articles were identified. Using the selection criteria, 38 studies were included for study. Most articles explored entomological indices weekly and devised unique geographic scales to aggregate human and/or mosquito data. The most used models were logistic and negative binomial regression. Maximum likelihood estimates (MLEs) and vector index (VI) demonstrated the greatest ratio of number of positive results to number of times tested. Among all selected articles, 35 unique U.S. locations assessed MLE and/or VI. Human WNV infection had a significant association with MLE across 81.25% (13/16) of locations. VI showed successful performance across 80.00% (24/30) sites tested. This systematic review identifies methods for quantifying relationships between entomological and human WNV infection data. We found entomological surveillance indices applied to human WNV risk should include a measure of virus presence, such as MLE and VI. Model type and covariates were too variable to identify geographic or species-specific trends, though, when tested, including temperature, land cover, population density, and time improved the model. This study is meant to be informative and designed to assist public health agencies in seasonal WNV preparations but are not meant to be a panacea for all WNV surveillance challenges.
• Sedda, L., Wrench, E., Moore, T. C., Wolfe, K., Tangena, J. A., & Brown, H. E. (2025).

  Challenges in the surveillance and control of mosquito-borne diseases in Europe and United States. The perspective from public health experts

  . One Health (Amsterdam, Netherlands), 21, 101133.
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  The complexity of mosquito-borne diseases and the necessity for cross-sector collaboration present significant challenges, requiring changes in laws, policies, and inter-agency agreements. In this qualitative study we purposively selected and interviewed public health managers from the European Union and United States involved in vector-borne disease surveillance and control and asked them about the barriers currently faced when engaging in their activities. The interviewees highlighted the differences in surveillance and control guidelines between the European Centre for Disease Prevention and Control and the US Centers for Disease Control and Prevention which reflect structural political differences between the European Union and United States. The lack of centralisation increases uncertainty in applying mosquito surveillance and control guidance. In addition, limited resources and modelling capabilities hinder effective surveillance and control. The public health agents recognised that community engagement and transparent communication are critical for gaining public support and to succeed in interventions, thus recognition of the values of these collaborations need to be accounted for in disease preparedness. Effective mosquito surveillance and control requires strong organisational bases, coordination among stakeholders, and sufficient resources, as advocate by one health frameworks. Addressing these challenges is urgent due to global trends like climate change and increased international travel, which may heighten the risk of mosquito-borne disease outbreaks.
• Sedda, L., Wrench, E., Moore, T. C., Wolfe, K., Tangena, J. A., & Brown, H. E. (2025). Challenges in the surveillance and control of mosquito-borne diseases in Europe and United States. The perspective from public health experts.. One Health, 21(Issue). doi:10.1016/j.onehlt.2025.101133
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  The complexity of mosquito-borne diseases and the necessity for cross-sector collaboration present significant challenges, requiring changes in laws, policies, and inter-agency agreements. In this qualitative study we purposively selected and interviewed public health managers from the European Union and United States involved in vector-borne disease surveillance and control and asked them about the barriers currently faced when engaging in their activities. The interviewees highlighted the differences in surveillance and control guidelines between the European Centre for Disease Prevention and Control and the US Centers for Disease Control and Prevention which reflect structural political differences between the European Union and United States. The lack of centralisation increases uncertainty in applying mosquito surveillance and control guidance. In addition, limited resources and modelling capabilities hinder effective surveillance and control. The public health agents recognised that community engagement and transparent communication are critical for gaining public support and to succeed in interventions, thus recognition of the values of these collaborations need to be accounted for in disease preparedness. Effective mosquito surveillance and control requires strong organisational bases, coordination among stakeholders, and sufficient resources, as advocate by one health frameworks. Addressing these challenges is urgent due to global trends like climate change and increased international travel, which may heighten the risk of mosquito-borne disease outbreaks.
• Tamari, N., Brown, H. E., Sedda, L., Riehle, M. A., Ellingson, K. D., Walker, K. R., Christopherson, G. L., Atieli, H., Munga, S., & Ernst, K. C. (2025).

  Structural features of outdoor latrines influence the abundance of Anopheles gambiae s.l. and Culex quinquefasciatus in a village in Kisumu County, western Kenya

  . Parasites & Vectors, 18(1), 364.
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  Malaria remains a leading cause of mortality in Kenya, despite concerted efforts in malaria vector control. Reducing outdoor transmission is a key factor in addressing residual malaria. Outdoor latrines are characterized as semi-sheltered structures with humid environments, which may provide an ideal resting site for Anopheles species to feed on human blood and subsequently rest. This study aimed to quantify the abundance of adult mosquitoes in houses and outdoor latrines, as well as explore the environmental factors associated with mosquito abundance.
• Tamari, N., Brown, H. E., Sedda, L., Riehle, M. A., Ellingson, K. D., Walker, K. R., Christopherson, G. L., Atieli, H., Munga, S., & Ernst, K. C. (2025). Structural features of outdoor latrines influence the abundance of Anopheles gambiae s.l. and Culex quinquefasciatus in a village in Kisumu County, western Kenya. Parasites and Vectors, 18(Issue 1). doi:10.1186/s13071-025-07011-7
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  Background: Malaria remains a leading cause of mortality in Kenya, despite concerted efforts in malaria vector control. Reducing outdoor transmission is a key factor in addressing residual malaria. Outdoor latrines are characterized as semi-sheltered structures with humid environments, which may provide an ideal resting site for Anopheles species to feed on human blood and subsequently rest. This study aimed to quantify the abundance of adult mosquitoes in houses and outdoor latrines, as well as explore the environmental factors associated with mosquito abundance. Methods: Monthly mosquito sampling was conducted in 50 houses and their corresponding outdoor latrines using Prokopack aspirators from July 2023 to April 2024. Household interviews were conducted concurrently to collect data on the number of individuals sleeping in the houses and the quantity of bednets used within the households. In addition, blood meal sources were identified through polymerase chain reaction (PCR) analysis of blood-fed mosquitoes collected from December 2023 to April 2024. Results: Among anopheline species, the An. funestus group was the most common, followed by An. gambiae s.l. in both houses and latrines. In anophelines, the human blood index was 50.0% (n = 15) in houses and 33.3% (n = 4) in latrines, while bovine blood was 60.0% (n = 18) and 66.7% (n = 8), respectively. Ventilated improved pit (VIP) latrines were associated with a 61% decrease in An. gambiae s.l. abundance (adjusted incidence rate ratio [aIRR] = 0.39, 95% confidence interval [CI] = 0.16–0.96) and a 62% decrease in Culex quinquefasciatus abundance (aIRR = 0.38, 95% CI = 0.24–0.60), compared with pit latrines. The presence of a bathing space in latrines was associated with a 23% increase in Cx. quinquefasciatus abundance (aIRR = 1.88, 95% CI = 1.23–2.89) compared with latrines without a bathing space. There was an inverse association between the number of individuals using the latrines and Cx. quinquefasciatus abundance (aIRR = 0.93, 95% CI = 0.89–0.97). Conclusions: VIP latrines were associated with a lower abundance of An. gambiae s.l. and Cx. quinquefasciatus compared with pit latrines, whereas the presence of a bathing space in latrines was associated with a higher abundance of Cx. quinquefasciatus compared with latrines without bathing spaces. Integrative public health programs that promote the construction of VIP latrines as a low-cost intervention may provide co-benefits for both sanitation and vector control.
• Austhof, E., Austhof, E., Brown, H., Brown, H., White, A., White, A., Jervis, R., Jervis, R., Weiss, J., Weiss, J., Davis, S., Davis, S., Shrum Davis, S., Shrum Davis, S., Moore, D., Moore, D., Pogreba-Brown, K., & Pogreba-Brown, K. (2024). Association between Precipitation Events, Drought, and Animal Operations with Campylobacter Infections in the Southwest United States, 2009–2021. Environmental Health Perspectives, 132(9). doi:10.1289/EHP14693
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  BACKGROUND: Weather variability is associated with enteric infections in people through a complex interaction of human, animal, and environmental factors. Although Campylobacter infections have been previously associated with precipitation and temperature, the association between precipitation and drought on campylobacteriosis has not been studied. OBJECTIVE: Using data from Arizona, Colorado, New Mexico, and counties in Utah, this ecological study aimed to assess the association between precipitation and the incidence of campylobacteriosis by county from 2009 to 2021 and to determine how this association is modified by prior drought level and animal operations. METHODS: We merged 38,782 cases of campylobacteriosis reported in 127 counties with total precipitation (in inches), temperature (in average degrees Fahrenheit), Palmer Drought Severity Index (PDSI, category), and animal census data (presence, density per square mile) by week from 2009 to 2021. Negative binomial generalized estimating equations adjusted for temperature with a 3-wk lag were used to explore the association between precipitation on campylobacteriosis with resulting incidence rate ratios (IRRs). Stratified analyses explored the association with precipitation following antecedent drought, presence of farm operations, and animal density. RESULTS: A 1-in (25:4 mm) increase in precipitation was associated with a 3% increase in campylobacteriosis reported 3 wks later (IRR = 1.03; 95% CI: 1.02, 1.04) after adjusting for average temperature and PDSI. Compared with normal conditions, there were significantly more cases when precipitation followed antecedent extremely wet (IRR = 1.15; 95% CI: 1.04, 1.26), very wet (IRR = 1.09; 95% CI: 1.01, 1.18), moderately wet (IRR = 1.06; 95% CI: 1.01, 1.12), moderate drought (IRR = 1.11; 95% CI: 1.07, 1.16), and severe drought (IRR = 1.06; 95% CI: 1.02, 1.11) conditions, whereas there were significantly fewer cases (IRR = 0.89; 95% CI: 0.85, 0.94) for antecedent extreme drought. Compared to counties with no animal opera-tions, counties with animal operations had significantly more cases following precipitation for every PDSI category except extreme drought. Counties with a higher density of beef cattle, goats for meat, chicken broilers, and chicken layers had significantly higher rates of campylobacteriosis following precipitation than those with no such operations, whereas those with dairy cattle and goats for milk, did not. DISCUSSION: In this majority arid and semiarid environment, precipitation following prior wet conditions and moderate and severe drought were significantly associated with increased rates of campylobacteriosis, and only in prior extreme drought did rates decrease. Where the precipitation fell made a difference; after precipitation, counties with farm operations had significantly more cases compared to counties without farm operations. Further work should assess individual-level risk factors within environmental exposure pathways for Campylobacter. https://doi.org/10.1289/EHP14693.
• Austhof, E., Brown, H. E., White, A. E., Jervis, R. H., Weiss, J., Shrum Davis, S., Moore, D., & Pogreba-Brown, K. (2024).

  Association between Precipitation Events, Drought, and Animal Operations with Infections in the Southwest United States, 2009-2021

  . Environmental Health Perspectives, 132(9), 97010.
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  Weather variability is associated with enteric infections in people through a complex interaction of human, animal, and environmental factors. Although infections have been previously associated with precipitation and temperature, the association between precipitation and drought on campylobacteriosis has not been studied.
• Austhof, E., Pogreba-Brown, K., White, A. E., Jervis, R. H., Weiss, J., Davis, S. S., Moore, D., & Brown, H. E. (2024).

  Association between precipitation events, drought, and animal operations with infections in the Southwest US, 2009-2021

  . One Health (Amsterdam, Netherlands), 19, 100941.
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  Temperature and precipitation have previously been associated with infections. The association between salmonellosis and precipitation might be explained by antecedent drought conditions; however, few studies have explored this effect.
• Austhof, E., Pogreba-Brown, K., White, A., Jervis, R., Weiss, J., Davis, S., Moore, D., & Brown, H. (2024). Association between precipitation events, drought, and animal operations with Salmonella infections in the Southwest US, 2009–2021. One Health, 19. doi:10.1016/j.onehlt.2024.100941
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  Background: Temperature and precipitation have previously been associated with Salmonella infections. The association between salmonellosis and precipitation might be explained by antecedent drought conditions; however, few studies have explored this effect. Methods: Using an ecological study design with public health surveillance, meteorological (total precipitation [inches], temperature [average °F], Palmer Drought Severity Index [PDSI, category]), and livestock data we explored the association between precipitation and Salmonella infections reported in 127/141 counties from 2009 to 2021 in the Southwest, US and determined how this association was modified by antecedent drought. To explore the acute effect of precipitation on Salmonella infections we used negative binomial generalized estimating equations adjusted for temperature with a 2-week lag resulting in Incidence Rate Ratios (IRR). Stratified analyses were used to explore the effect of antecedent drought and type of animal density on this association. Results: A one inch increase in precipitation was associated with a 2 % increase in Salmonella infections reported two weeks later (IRR: 1.02, 95 % CI: 1.00, 1.04) after adjusting for average temperature and PDSI. Precipitation following moderate (IRR: 1.22, 95 % CI: 1.17, 1.28) and severe drought (IRR: 1.16, 95 % CI: 1.10, 1.22) was associated with a significant increase in cases, whereas in the most extreme drought conditions, cases were significantly decreased (IRR: 0.89, 95 % CI: 0.85, 0.94). Overall, more precipitation (above a 30-year normal, the 95th and 99th percentiles) were associated with greater increases in cases, with the highest increase following moderate and severe drought. Counties with a higher density of chicken and beef cattle were significantly associated with increased cases regardless of drought status, whereas dairy cattle, and cattle including calves had mixed results. Discussion: Our study suggests precipitation following prior dry conditions is associated with an increase in salmonellosis in the Southwest, US. Public health is likely to see an increase in salmonellosis with extreme precipitation events, especially in counties with a high density of chicken and beef cattle.
• Austhof, E., Warner, S., Helfrich, K., Pogreba-Brown, K., Brown, H. E., Klimentidis, Y. C., Scallan Walter, E., Jervis, R. H., & White, A. E. (2024).

  Exploring the association of weather variability on Campylobacter - A systematic review

  . Environmental Research, 252(Pt 1), 118796.
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  Previous work has found climate change-induced weather variability is suspected to increase the transmission of enteric pathogens, including Campylobacter, a leading cause of bacterial gastroenteritis. While the relationship between extreme weather events and diarrheal diseases has been documented, the specific impact on Campylobacter infections remains underexplored.
• Brown, H. E., Begay, R. L., Sanderson, P. R., Chief, C., Lameman, B., & Harris, R. B. (2024).

  Healthcare access, attitudes and behaviours among Navajo adults during the COVID-19 pandemic: a cross-sectional study

  . BMJ Public Health, 2(1).
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  To assess factors associated with positive COVID-19 tests, perspectives on health-related care delivery during pandemic, and factors supporting resilience among members of the Navajo Nation.
• Watkins, L., Brown, H. E., Keith, L., Austhof, E., Lin, H., Chambers, S. N., Tabor, J., Gettel, A., & Guardaro, M. (2024). A Co-Produced Workflow for Addressing Inequities in Cooling Center Access. Community Science, 3(4), e2023CSJ000038.
• Watkins, L., Brown, H. E., Keith, L., Cox, H. L., Austhof, E., Chambers, S., Tabor, J., Gettel, A., & Guardaro, M. (2024).

  A co-produced workflow for addressing inequities in cooling center access.

  . Community Science, 3(4), e2023CSJ000038. doi:10.1029/2023CSJ000038
• Woodson, L. L., Garcia Saldivar, A., Brown, H. E., Magrath, P. A., Farland, L. V., Blas, M. M., & Madhivanan, P. (2024).

  'You have a lot of mirrors': structural and socioecological factors impacting adolescent pregnancy and reproductive health in the Amazon basin, Peru, a qualitative study

  . Culture, Health & Sexuality, 1-17.
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  Loreto, in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country. However, underlying causes of adolescent pregnancy are not fully understood as data are limited in Indigenous and remote Amazonian communities. This study investigated adolescent reproductive health within Loreto using an ecological systems framework. Forty-one semi-structured interviews were conducted in June 2022: community leaders ( = 12) and adolescent participants between 15 and 17 years of age (pregnant girls,  = 11; never pregnant girls,  = 9; and boys,  = 9). We also conducted focus group discussions with community health workers and educators in October 2022 (three focus groups,  = 15). Adolescent reproductive health is complex with multi-layered factors that put girls at higher risk of pregnancy. We found a paradoxical relationship between expected social and gender norms and individual desires. This research provides a contextual understanding of the lived experience of adolescents and young people in the Amazon region of Peru. Our findings suggest the need for greater exploration of the contradictory ideas surrounding adolescent pregnancy and female sexuality.
• Woodson, L. L., Garcia Saldivar, A., Brown, H. E., Magrath, P. A., Farland, L. V., Blas, M. M., & Madhivanan, P. (2024). ‘You have a lot of mirrors’: structural and socioecological factors impacting adolescent pregnancy and reproductive health in the Amazon basin, Peru, a qualitative study. Culture, Health and Sexuality, 26(Issue 10). doi:10.1080/13691058.2024.2308666
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  Loreto, in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country. However, underlying causes of adolescent pregnancy are not fully understood as data are limited in Indigenous and remote Amazonian communities. This study investigated adolescent reproductive health within Loreto using an ecological systems framework. Forty-one semi-structured interviews were conducted in June 2022: community leaders (n = 12) and adolescent participants between 15 and 17 years of age (pregnant girls, n = 11; never pregnant girls, n = 9; and boys, n = 9). We also conducted focus group discussions with community health workers and educators in October 2022 (three focus groups, n = 15). Adolescent reproductive health is complex with multi-layered factors that put girls at higher risk of pregnancy. We found a paradoxical relationship between expected social and gender norms and individual desires. This research provides a contextual understanding of the lived experience of adolescents and young people in the Amazon region of Peru. Our findings suggest the need for greater exploration of the contradictory ideas surrounding adolescent pregnancy and female sexuality.
• Woodson, L. L., Woodson, L. L., Saldivar, A. G., Garcia Saldivar, A., Brown, H. E., Brown, H. E., Magrath, P. A., Magrath, P. A., de Mayolo, N. A., Antunez de Mayolo, N., Pettygrove, S., Pettygrove, S., Farland, L. V., Farland, L. V., Madhivanan, P., Madhivanan, P., Blas, M. M., & Blas, M. M. (2024). The downstream effects of COVID-19 on adolescent girls in the Peruvian Amazon: qualitative findings on how the pandemic affected education and reproductive health. BMJ Global Health, 9(4).
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  Due to COVID-19, schools were closed to mitigate disease spread. Past studies have shown that disruptions in education have unintended consequences for adolescents, including increasing their risk of school dropout, exploitation, gender-based violence, pregnancy and early unions. In Peru, the government closed schools from March 2020 to March 2022, declaring a national emergency that affected an estimated 8 million children. These closures may have unintended consequences, including increased adolescent pregnancy, particularly in Peru's rural, largely indigenous regions. Loreto, located in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country and poor maternal and child health outcomes. The underlying causes may not be fully understood as data are limited, especially as we transition out of the pandemic. This qualitative study investigated the downstream effects of COVID-19 on adolescent education and reproductive health in Loreto's districts of Nauta and Parinari. In-depth interviews (n=41) were conducted with adolescents and community leaders. These were held in June 2022, 3 months after the reinstitution of in-person classes throughout Peru. Focus group discussions (FGDs) were also completed with community health workers and educators from the same study area in October 2022 to supplement our findings (3 FGDs, n=15). We observed that the economic, educational and health effects of the COVID-19 pandemic contributed to reduced contraceptive use, and increased school abandonment, early unions and adolescent pregnancy. The interplay between adolescent pregnancy and both early unions and school abandonment was bidirectional, with each acting as both a cause and consequence of the other.
• Yang, H., Pan, F., Tong, D., Brown, H. E., & Liu, J. (2024). Measurement error tolerant Poisson regression for Valley Fever incidence prediction. IISE Transactions on Healthcare Systems Engineering, 14(4), 305-317.
• Austhof, E., Keith, L., Brown, H. E., & Chambers, S. (2023). Development of a Geographic Human Heat Balance Equation to Support Public Health Analyses: An Arizona Urban Sun Corridor application. Remote Sensing Applications: Society and Environment., 32(2023), 101009. doi:10.1016/j.rsase.2023.101009
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  Land surface temperature (LST) estimates often serve as urban heat islands maps and to infer human thermal comfort. Parallel to this, physiological heat balance calculations have been well documented to measure changes in body core temperature and measure risk of heat-related illness. However, there is a need for an improved spatially explicit method to assess human thermal comfort. Using spatial climate data measuring temperature, airflow, and humidity, we developed a geographic body heat storage (BHS) model based on heat exchange and evaporative heat loss from the human body. As proof of concept, we used heat-related illness emergency department visits in two Arizona metropolitan areas to demonstrate that BHS can improve LST's shortcomings, with its increased explanatory power of and linear fit to emergency records. The BHS model can support decision making for public health outcomes as heat risk increases with climate change and urban overheating to more closely approximate the human heat experience. BHS allows can be implemented in different climate regions and with investigations of additional physiological and community variables to better describe risk of heat-related illness.
• Bailey, K. S., Brown, H. E., Lekic, V., Pradeep, K., Merchant, J. L., & Harris, R. B. (2023). Helicobacter pylori treatment knowledge, access and barriers: A cross-sectional study. Helicobacter, 28(2), e12954.
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  Helicobacter pylori (Hp) is among the most common bacterial infections in the world and one of the most common infectious agents linked to malignancy, gastric cancer (GC). Within the US there is high disparity in the rates of Hp infection and associated diseases. Hp infection is treatable, and knowledge may influence screening and treatment seeking behaviors.
• Bailey, K. S., Brown, H. E., Lekic, V., Pradeep, K., Merchant, J. L., & Harris, R. B. (2023). Helicobacter pylori treatment knowledge, access and barriers: A cross-sectional study. Helicobacter, 28(Issue 2). doi:10.1111/hel.12954
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  Background: Helicobacter pylori (Hp) is among the most common bacterial infections in the world and one of the most common infectious agents linked to malignancy, gastric cancer (GC). Within the US there is high disparity in the rates of Hp infection and associated diseases. Hp infection is treatable, and knowledge may influence screening and treatment seeking behaviors. Materials and Methods: In this cross-sectional study of 1042 respondents recruited from the Online Amazon MTurk platform, we sought to assess baseline knowledge of Hp and to gain insight into barriers related to Hp care. Results: Just over half (52.3%) reported some prior knowledge of Hp with 11.7% (n = 122) reporting being treated for Hp themselves and 21.4% reporting family members diagnosed with Hp. Of respondents reporting prior treatment, 95 (78%) reported GI upset and 27 (21%) reported not completing medications. Specific to Hp and GC, 70% indicated that a belief that the treatment was worse than the symptoms would affect their willingness to seek care, while 81% indicated knowing Hp can cause GC would affect their treatment decisions and knowing their gastric symptoms were caused by Hp would affect their willingness to receive care. Conclusions: Knowledge of Hp in this US sample of online respondents is low and self-reported difficulties with treatment compliance is high. Increasing awareness of this infection and addressing the challenges to treatment compliance could potentially reduce rates of Hp antibiotic resistance and progression to GC or other complications of Hp infection.
• Brown, H. E., Austhof, E., Luz, P. M., & Ferguson, D. B. (2023). Economics, health, or environment: What motivates individual climate action?. PLOS Climate, 2(Issue 8). doi:10.1371/journal.pclm.0000177
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  Climate change is a major threat to human health, however the role of health in climate change communication is understudied. The goal of this study was to understand how to support individuals’ adoption of climate related mitigation and adaptation activities. We hypothesized the primary motivation for engaging in pro-environmental activities would be unequally distributed across health, economics, or environment motivations. We also hypothesized respondents who felt greater susceptibility and those with higher perceived self-efficacy would adopt more pro-environmental behaviors. In 2020, we conducted a cross-sectional study using Amazon’s MTurk platform. Among the respondents, the most commonly reported activity was alternatives to private vehicles (30% already engaging), while more than two thirds of respondents reported wanting to install solar panels (70.1%) and converting to a high efficiency vehicle (63.2%). Depending on the action, respondents’ reported motivation varied. Economics was common to those who used public transportation and who installed solar paneling; purchasing a high efficiency vehicle was split between environment and economic reasons. Health was the primary motivation for converting to a plant-based diet. The perceived immediacy of climate change impacts was associated with adoption of pro-climate activities as were beliefs around human capacity to mitigate climate change. Despite the growing literature supporting health as a motivation for climate action, economic motivation was more commonly selected among the activities we evaluated. These results could aid the development of more efficient evidence-based communication strategies that would reach various audiences in society.
• Chambers, S. N., Brown, H. E., Keith, L., & Austhof, E. (2023). Development of a geographic human heat balance equation to support public health analyses: An Arizona urban sun corridor application. Remote Sensing Applications: Society and Environment, 32. doi:10.1016/j.rsase.2023.101009
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  Land surface temperature (LST) estimates often serve as urban heat islands maps and to infer human thermal comfort. Parallel to this, physiological heat balance calculations have been well documented to measure changes in body core temperature and measure risk of heat-related illness. However, there is a need for an improved spatially explicit method to assess human thermal comfort. Using spatial climate data measuring temperature, airflow, and humidity, we developed a geographic body heat storage (BHS) model based on heat exchange and evaporative heat loss from the human body. As proof of concept, we used heat-related illness emergency department visits in two Arizona metropolitan areas to demonstrate that BHS can improve LST's shortcomings, with its increased explanatory power of and linear fit to emergency records. The BHS model can support decision making for public health outcomes as heat risk increases with climate change and urban overheating to more closely approximate the human heat experience. BHS allows can be implemented in different climate regions and with investigations of additional physiological and community variables to better describe risk of heat-related illness.
• Dennis, L. K., Brown, H. E., & Arrington, A. K. (2023). Comparison of Prognostic Factors for Merkel Cell Carcinoma, Mucosal Melanoma and Cutaneous Malignant Melanoma: Insights into Their Etiologies. Current Oncology, 30(Issue 4). doi:10.3390/curroncol30040301
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  Little is known about the epidemiology of Merkel cell carcinoma (MCC) and mucosal melanoma (MM). Using the United States (US) National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program data, we compared MCC and MM with cutaneous malignant melanoma (CMM) with respect to incidence rates and prognostic factors to better understand disease etiologies. We describe the proportional incidences of the three cancers along with their survival rates based on 20 years of national data. The incidence rates in 2000–2019 were 203.7 per 1,000,000 people for CMM, 5.9 per 1,000,000 people for MCC and 0.1 per 1,000,000 people for MM. The rates of these cancers increased over time, with the rate of MM tripling between 2000–2009 and 2010–2019. The incidences of these cancers increased with age and rates were highest among non-Hispanic Whites. Fewer MCCs and MMS were diagnosed at the local stage compared with CMM. The cases in the 22 SEER registries in California were not proportional to the 2020 population census but instead were higher than expected for CMM and MCC and lower than expected for MM. Conversely, MM rates were higher than expected in Texas and New York. These analyses highlight similarities in the incidence rates of CMM and MCC—and differences between them and MM rates—by state. Understanding more about MCC and MM is important because of their higher potential for late diagnosis and metastasis, which lead to poor survival.
• Dennis, L. K., Brown, H. E., & Arrington, A. K. (2023). Comparison of Prognostic Factors for Merkel Cell Carcinoma, Mucosal Melanoma and Cutaneous Malignant Melanoma: Insights into Their Etiologies. Current oncology (Toronto, Ont.), 30(4), 3974-3988.
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  Little is known about the epidemiology of Merkel cell carcinoma (MCC) and mucosal melanoma (MM). Using the United States (US) National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program data, we compared MCC and MM with cutaneous malignant melanoma (CMM) with respect to incidence rates and prognostic factors to better understand disease etiologies. We describe the proportional incidences of the three cancers along with their survival rates based on 20 years of national data. The incidence rates in 2000-2019 were 203.7 per 1,000,000 people for CMM, 5.9 per 1,000,000 people for MCC and 0.1 per 1,000,000 people for MM. The rates of these cancers increased over time, with the rate of MM tripling between 2000-2009 and 2010-2019. The incidences of these cancers increased with age and rates were highest among non-Hispanic Whites. Fewer MCCs and MMS were diagnosed at the local stage compared with CMM. The cases in the 22 SEER registries in California were not proportional to the 2020 population census but instead were higher than expected for CMM and MCC and lower than expected for MM. Conversely, MM rates were higher than expected in Texas and New York. These analyses highlight similarities in the incidence rates of CMM and MCC-and differences between them and MM rates-by state. Understanding more about MCC and MM is important because of their higher potential for late diagnosis and metastasis, which lead to poor survival.
• Kamana, E., Bai, D., Brown, H. E., & Zhao, J. (2023). The malaria transmission in Anhui province China. Infectious Disease Modelling, 8(1), 1-10.
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  cases have opposite trends in Anhui China in the past decade. Long term and seasonal trends in the transmission rate of in Africa has been well studied, however that of transmitted by in China has not been investigated. There is a lot of work on the relationship between cases and climatic factors in China, with sometimes contradicting results. However, how climatic factors affect transmission rate of in China is unknown. We used Anhui province as an example to analyze the recent transmission dynamics where two types of malaria have been reported with differing etiologies. We examined breakpoints of the and malaria long term dynamics in the recent decade. For locally transmitted malaria, we analyzed the transmission rate and its seasonality using the combined human and mosquitos SIR-SI model with time-varied mosquito biting rate. We identified the effects of meteorological factors on the seasonality in transmission rate using a GAM model. For the imported malaria, we analyzed the potential reason for the observed increase in cases. The breakpoints of and dynamics happened in a same year, 2010. The seasonality in the transmission rate of malaria was high (42.4%) and was linearly associated with temperature and nonlinearly with rainfall. The abrupt increase in imported cases after the breakpoint was significantly related to the increased annual Chinese investment in Africa. Under the conditions of the existing vectors of malaria, long-term trends in climatic factors, and increasing trend in migration to/from endemic areas and imported malaria cases, we should be cautious of the possibility of the reestablishment of malaria in regions where it has been eliminated or the establishment of other vector-borne diseases.
• Kamana, E., Bai, D., Brown, H. E., & Zhao, J. (2023). The malaria transmission in Anhui province China. Infectious Disease Modelling, 8(Issue 1). doi:10.1016/j.idm.2022.11.009
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  Plasmodium vivax and Plasmodium falciparum cases have opposite trends in Anhui China in the past decade. Long term and seasonal trends in the transmission rate of P. falciparum in Africa has been well studied, however that of P. vivax transmitted by Anopheles sinensis in China has not been investigated. There is a lot of work on the relationship between P. vivax cases and climatic factors in China, with sometimes contradicting results. However, how climatic factors affect transmission rate of P. vivax in China is unknown. We used Anhui province as an example to analyze the recent transmission dynamics where two types of malaria have been reported with differing etiologies. We examined breakpoints of the P. vivax and P. falciparum malaria long term dynamics in the recent decade. For locally transmitted P. vivax malaria, we analyzed the transmission rate and its seasonality using the combined human and mosquitos SIR-SI model with time-varied mosquito biting rate. We identified the effects of meteorological factors on the seasonality in transmission rate using a GAM model. For the imported P. falciparum malaria, we analyzed the potential reason for the observed increase in cases. The breakpoints of P. vivax and P. falciparum dynamics happened in a same year, 2010. The seasonality in the transmission rate of P. vivax malaria was high (42.4%) and was linearly associated with temperature and nonlinearly with rainfall. The abrupt increase in imported P. falciparum cases after the breakpoint was significantly related to the increased annual Chinese investment in Africa. Under the conditions of the existing vectors of malaria, long-term trends in climatic factors, and increasing trend in migration to/from endemic areas and imported malaria cases, we should be cautious of the possibility of the reestablishment of malaria in regions where it has been eliminated or the establishment of other vector-borne diseases.
• Monroy, F. P., Brown, H. E., Acevedo-Solis, C. M., Rodriguez-Galaviz, A., Dholakia, R., Pauli, L., & Harris, R. B. (2023). Antibiotic Resistance Rates for in Rural Arizona: A Molecular-Based Study. Microorganisms, 11(9).
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  () is a common bacterial infection linked to gastric malignancies. While infection and gastric cancer rates are decreasing, antibiotic resistance varies greatly by community. Little is known about resistance rates among rural Indigenous populations in the United States. From 2018 to 2021, 396 endoscopy patients were recruited from a Northern Arizona clinic, where community prevalence is near 60%. Gastric biopsy samples positive for ( = 67) were sequenced for clarithromycin- and metronidazole-associated mutations, 23S ribosomal RNA (23S), and oxygen-insensitive NADPH nitroreductase () regions. Medical record data were extracted for endoscopic findings and prior history. Data analysis was restricted to individuals with no history of infection. Of 49 individuals, representing 64 samples which amplified in the 23S region, a clarithromycin-associated mutation was present in 38.8%, with T2182C being the most common mutation at 90%. While the prevalence of metronidazole-resistance-associated mutations was higher at 93.9%, the mutations were more variable, with D95N being the most common followed by L62V. No statistically significant sex differences were observed for either antibiotic. Given the risk of treatment failure with antibiotic resistance, there is a need to consider resistance profile during treatment selection. The resistance rates in this population of American Indian patients undergoing endoscopy are similar to other high-risk populations. This is concerning given the high prevalence and low rates of resistance testing in clinical settings. The mutations reported are associated with antibiotic resistance, but clinical resistance must be confirmed.
• Monroy, F. P., Brown, H. E., Acevedo-Solis, C. M., Rodriguez-Galaviz, A., Dholakia, R., Pauli, L., & Harris, R. B. (2023). Antibiotic Resistance Rates for Helicobacter pylori in Rural Arizona: A Molecular-Based Study. Microorganisms, 11(Issue 9). doi:10.3390/microorganisms11092290
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  Helicobacter pylori (H. pylori) is a common bacterial infection linked to gastric malignancies. While H. pylori infection and gastric cancer rates are decreasing, antibiotic resistance varies greatly by community. Little is known about resistance rates among rural Indigenous populations in the United States. From 2018 to 2021, 396 endoscopy patients were recruited from a Northern Arizona clinic, where community H. pylori prevalence is near 60%. Gastric biopsy samples positive for H. pylori (n = 67) were sequenced for clarithromycin- and metronidazole-associated mutations, 23S ribosomal RNA (23S), and oxygen-insensitive NADPH nitroreductase (rdxA) regions. Medical record data were extracted for endoscopic findings and prior H. pylori history. Data analysis was restricted to individuals with no history of H. pylori infection. Of 49 individuals, representing 64 samples which amplified in the 23S region, a clarithromycin-associated mutation was present in 38.8%, with T2182C being the most common mutation at 90%. While the prevalence of metronidazole-resistance-associated mutations was higher at 93.9%, the mutations were more variable, with D95N being the most common followed by L62V. No statistically significant sex differences were observed for either antibiotic. Given the risk of treatment failure with antibiotic resistance, there is a need to consider resistance profile during treatment selection. The resistance rates in this population of American Indian patients undergoing endoscopy are similar to other high-risk populations. This is concerning given the high H. pylori prevalence and low rates of resistance testing in clinical settings. The mutations reported are associated with antibiotic resistance, but clinical resistance must be confirmed.
• Sanderson, P. R., Monroy, F. P., Brown, H. E., & Harris, R. B. (2023). Abstract IA008: Weaving university and community-based partnership. Cancer Epidemiology, Biomarkers & Prevention, 32(12_Supplement), IA008-IA008. doi:10.1158/1538-7755.disp23-ia008
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  Abstract Introduction/Background Including Hypothesis/Objectives: University investigators affiliated with the Partnership for Native American Cancer Prevention (NACP) and Navajo Nation partners worked together with a goal to estimate the prevalence of Helicobacter pylori infection and its specific subtypes and factors associated with infection. Methods: This partnership required multiple strategies to promote awareness and individual participation in this study. The team started with tribal resolutions and communication network with local Chapter House officers, Community Health Representatives (CHRs), local Navajo translators, Diné Haatalii Association (Navajo Medicine Man), social network outreach, and community healthcare providers. Results: Our population-based study weaved together various networks with local leaders, social media, and the Navajo Healthy Stomach website. Participant follow-up after testing found that local hospitals were overwhelmed with requests for appointments and immediate treatment. Participants reported side-effects of prescribed medications. The Monroy lab revealed enough biopsies to test for Helicobacter pylori infection. Conclusions: Successful studies must utilize both Navajo Nation Human Research and Review Board approvals with university Institutional Review Boards (IRBs). Local, in-person, radio, and social media-based weaving of culturally sensitive communications develops strong partnerships between university and community-based local people, programs, and hospitals. Future Directions (Opportunities and Challenges): The team continues to study the role of Helicobacter pylori on the gastrointestinal microbiome in the development of gastric disease in infected Navajo patients. Further outreach is ongoing with local community and providers. Funding Support: Partnership for Native American Cancer Prevention, U54 NCI grant. Citation Format: Priscilla R. Sanderson, Fernando Monroy, Heidi Brown, Robin Harris. Weaving university and community-based partnership [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr IA008.
• Austhof, E., & Brown, H. E. (2022). Global Warming's Six MTurks: A Secondary Analysis of a US-Based Online Crowdsourcing Market. International journal of environmental research and public health, 19(14).
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  Using a global warming audience segmentation tool (Six Americas Super Short Survey (SASSY)) as a case study, we consider how public health can use consumer panels and online crowdsourcing markets (OCMs) in research. Through a secondary analysis, we aim to understand how consumer panels and OCMs are similar to or different from each other on demographics and global warming beliefs through SASSY, and how they compare to US Census estimates. With this information, researchers will understand public opinion of global warming in their sample, which is useful for many climate change initiatives. Neither the consumer panel (Ipsos) or OCM sample (MTurk) matched US estimates of population demographics. Both panels achieved similar SASSY segments, showing that even with diverse sampling frames, SASSY is a useful tool for understanding global warming sentiment. Compared to Ipsos, MTurk was younger (more Millennials and Generation X), had higher educational attainment, and lower income. Both panels were majority White, but Ipsos was more diverse than the unweighted MTurk. Ipsos had more respondents from the South whereas MTurk had more respondents from the West. Across the MTurk SASSY segment, there were no significant differences for the majority of demographic characteristics except for age; younger generations were more Alarmed or Concerned, and older generations were more Doubtful and Dismissive. Researchers interested in understanding their sample's opinions of global warming should use SASSY and consider oversampling in key demographic variables if they intend to achieve a nationally representative and diverse sample.
• Austhof, E., & Brown, H. E. (2022). Global Warming’s Six MTurks: A Secondary Analysis of a US-Based Online Crowdsourcing Market. International Journal of Environmental Research and Public Health, 19(Issue 14). doi:10.3390/ijerph19148320
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  Using a global warming audience segmentation tool (Six Americas Super Short Survey (SASSY)) as a case study, we consider how public health can use consumer panels and online crowdsourcing markets (OCMs) in research. Through a secondary analysis, we aim to understand how consumer panels and OCMs are similar to or different from each other on demographics and global warming beliefs through SASSY, and how they compare to US Census estimates. With this information, researchers will understand public opinion of global warming in their sample, which is useful for many climate change initiatives. Neither the consumer panel (Ipsos) or OCM sample (MTurk) matched US estimates of population demographics. Both panels achieved similar SASSY segments, showing that even with diverse sampling frames, SASSY is a useful tool for understanding global warming sentiment. Compared to Ipsos, MTurk was younger (more Millennials and Generation X), had higher educational attainment, and lower income. Both panels were majority White, but Ipsos was more diverse than the unweighted MTurk. Ipsos had more respondents from the South whereas MTurk had more respondents from the West. Across the MTurk SASSY segment, there were no significant differences for the majority of demographic characteristics except for age; younger generations were more Alarmed or Concerned, and older generations were more Doubtful and Dismissive. Researchers interested in understanding their sample’s opinions of global warming should use SASSY and consider oversampling in key demographic variables if they intend to achieve a nationally representative and diverse sample.
• Brown, H. E., Keith, L., Madera-Garcia, V., Taylor, A., Ramirez, N., & Ogata, I. (2022). Greening Up For Mosquitoes: A Comparison of Green Stormwater Infrastructure in a Semiarid Region. Journal of the American Mosquito Control Association, 38(2), 109-112.
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  Green stormwater infrastructure provides environmental, economic, and health benefits as a strategy for building resilience against climate change impacts. However, it may inadvertently increase vulnerability due to improper design and construction or lack of maintenance. We engaged city stakeholders and a diverse student group to investigate possible maladaptation. After rain events, student interns collected data at green stormwater infrastructure, identified in partnership with city stakeholders, for both water retention and mosquito larvae, if present. During the sampling period in 2018, 24 rain events occurred, with 28 sites visited 212 times including visits to basins (63%), curb cuts (34%), and a bioswale (2%). The largest basin consistently retained water (mean: 3.3 days, SD: 2.3 days) and was a positive site for Culex quinquefasciatus, a West Nile virus vector. We found that while basins can become mosquito breeding habitat, there was no evidence that curb cuts were collecting and retaining water long enough. As cities turn to green stormwater infrastructure to address climate change impacts of increasing drought, flooding, and extreme heat, these findings can help in the selection of appropriate infrastructure design typologies.
• Brown, H., Keith, L., Madera-Garcia, V., Taylor, A., Ramirez, N., & Ogata, I. (2022). GREENING UP FOR MOSQUITOES: A COMPARISON OF GREEN STORMWATER INFRASTRUCTURE IN A SEMIARID REGION. Journal of the American Mosquito Control Association, 38(2). doi:10.2987/21-7055
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  Green stormwater infrastructure provides environmental, economic, and health benefits as a strategy for building resilience against climate change impacts. However, it may inadvertently increase vulnerability due to improper design and construction or lack of maintenance. We engaged city stakeholders and a diverse student group to investigate possible maladaptation. After rain events, student interns collected data at green stormwater infrastructure, identified in partnership with city stakeholders, for both water retention and mosquito larvae, if present. During the sampling period in 2018, 24 rain events occurred, with 28 sites visited 212 times including visits to basins (63%), curb cuts (34%), and a bioswale (2%). The largest basin consistently retained water (mean: 3.3 days, SD: 2.3 days) and was a positive site for Culex quinquefasciatus, a West Nile virus vector. We found that while basins can become mosquito breeding habitat, there was no evidence that curb cuts were collecting and retaining water long enough. As cities turn to green stormwater infrastructure to address climate change impacts of increasing drought, flooding, and extreme heat, these findings can help in the selection of appropriate infrastructure design typologies.
• Catalfamo, C. J., Brown, H. E., & Dennis, L. K. (2022). Evaluating the Strength of Association of Human Papillomavirus Infection With Penile Carcinoma: A Meta-Analysis. Sexually Transmitted Diseases, 49(Issue 5). doi:10.1097/olq.0000000000001606
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  Background Human papillomavirus (HPV) is a common sexually transmitted infection that is strongly associated with cervical cancer. A link to penile cancers has been suggested by case series. We sought to assess the strength of the association between HPV infection and penile cancer by meta-analysis. Methods A literature search to identify population-based studies evaluating the risk of HPV infection with penile cancer was conducted via PubMed and Google Scholar databases through December 2020. Studies were included in the pooled analyses if they presented relative risk (RR) estimates comparing penile cancer cases with noncases by HPV exposure status. They were stratified by (1) type of HPV, (2) test used to determine past HPV infection, and (3) the penile cancer type. Pooled analyses were conducted for stratum with at least 2 independent studies using fixed-effects and random-effects models. Results Fourteen articles representing 9 study populations fit the inclusion criteria and were included in the pooled analysis. Based on these studies, the pooled RRs are 2.9 (95% confidence interval [CI], 1.7-5.0; n = 4 studies) for invasive penile cancer and seropositivity to HPV16 L1, 4.5 (95% CI, 1.3-15.5; n = 2) for seropositivity to HPV18, and 8.7 for anogenital warts (95% CI, 5.1-14.8; n = 5). For the 3 studies reporting invasive and in situ penile cancer, the risk was 7.6 for anogenital warts. Conclusions The pooled RRs indicate up to a 4.5-fold increased risk between seropositivity for HPV infection and invasive penile cancer. This is much lower than associations seen between HPV and cervical cancer.
• Catalfamo, C. J., Brown, H. E., & Dennis, L. K. (2022). Evaluating the Strength of Association of Human Papillomavirus Infection With Penile Carcinoma: A Meta-Analysis. Sexually transmitted diseases, 49(5), 368-376.
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  Human papillomavirus (HPV) is a common sexually transmitted infection that is strongly associated with cervical cancer. A link to penile cancers has been suggested by case series. We sought to assess the strength of the association between HPV infection and penile cancer by meta-analysis.
• Chakravarti, I., Miranda-Schaeubinger, M., Ruiz-Remigio, A., Briones-Garduño, C., Fernández-Figueroa, E. A., Villanueva-Cabello, C. C., Borge-Villareal, A., Bejar-Ramírez, Y., Pérez-González, A., Rivera-Benitez, C., Oren, E., Brown, H. E., Becker, I., & Gilman, R. H. (2022). Chagas Disease in Pregnant Women from Endemic Regions Attending the Hospital General de Mexico, Mexico City. Tropical Medicine and Infectious Disease, 7(Issue 1). doi:10.3390/tropicalmed7010008
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  Trypanosoma cruzi infection leads to Chagas disease (CD), a neglected tropical infection of significant public health importance in South and Central America and other, non-endemic, countries. Pregnant women and their children are of particular importance to screen as T. cruzi can be transmitted vertically. The objective of this study was to screen for T. cruzi infection among pregnant women from endemic areas seen at the Hospital General de Mexico for prenatal care, so that they and their children may be quickly connected to CD treatment. Pregnant women were recruited through the hospital prenatal clinic and screened for T. cruzi infection using a series of serological and molecular tests. Of 150 screened patients, mean age 26.8 (SD 6.4), 30 (20.0%) were positive by at least one diagnostic test. Of these, only nine (6%) were positive as determined by PCR. Diagnosis of chronic CD is difficult in endemic places like Mexico due to the limitations of current commercially available diagnostic tests. Further evaluation of diagnostic performance of various assays could improve current CD diagnostic algorithms and proper care management in these regions. Genetic variability in the parasite may also play a role in the differing assay performances seen in this study, and this may be a valuable avenue of further research.
• Harris, R. B., Brown, H. E., Begay, R. L., Sanderson, P. R., Chief, C., Monroy, F. P., & Oren, E. (2022). Helicobacter pylori Prevalence and Risk Factors in Three Rural Indigenous Communities of Northern Arizona. International Journal of Environmental Research and Public Health, 19(Issue 2). doi:10.3390/ijerph19020797
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  Helicobacter pylori (H. pylori) is one of the most common bacterial stomach infections and is implicated in a majority of non-cardia gastric cancer. While gastric cancer has decreased in the United States (US), the incidence in the Navajo Nation is nearly four times higher than surrounding Non-Hispanic White populations. Little is known about H. pylori prevalence in this population or other Indigenous communities in the lower 48 states. In this cross-sectional study, 101 adults representing 73 households from three Navajo Nation chapter communities completed surveys and a urea breath test for active H. pylori. Accounting for intrahousehold correlation, H. pylori prevalence was 56.4% (95% CI, 45.4–66.8) and 72% of households had at least one infected person. The odds of having an active infection in households using unregulated water were 8.85 (95% CI, 1.50–53.38) that of the use of regulated water, and males had 3.26 (95% CI, 1.05–10.07) higher odds than female. The prevalence of H. pylori in Navajo is similar to that seen in Alaska Natives. Further investigation into factors associated with prevention of infection is needed as well as understanding barriers to screening and treatment.
• Langston, M. E., Brown, H. E., Lynch, C. F., Roe, D. J., & Dennis, L. K. (2022). Ambient UVR and Environmental Arsenic Exposure in Relation to Cutaneous Melanoma in Iowa. International Journal of Environmental Research and Public Health, 19(Issue 3). doi:10.3390/ijerph19031742
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  Intermittent sun exposure is the major environmental risk factor for cutaneous melanoma (CM). Cumulative sun exposure and other environmental agents, such as environmental arsenic exposure, have not shown consistent associations. Ambient ultraviolet radiation (UVR) was used to measure individual total sun exposure as this is thought to be less prone to misclassification and recall bias. Data were analyzed from 1096 CM cases and 1033 controls in the Iowa Study of Skin Cancer and Its Causes, a population-based, case-control study. Self-reported residential histories were linked to satellite-derived ambient UVR, spatially derived environmental soil arsenic concentration, and drinking water arsenic concentrations. In men and women, ambient UVR during childhood and adolescence was not associated with CM but was positively associated during adulthood. Lifetime ambient UVR was positively associated with CM in men (OR for highest vs. lowest quartile: 6.09, 95% confidence interval (CI) 2.21–16.8), but this association was not as strong among women (OR for highest vs. lowest quartile: 2.15, 95% CI 0.84–5.54). No association was detected for environmental soil or drinking water arsenic concentrations and CM. Our findings suggest that lifetime and adulthood sun exposures may be important risk factors for CM.
• Monroy, F. P., Brown, H. E., Sanderson, P. R., Jarrin, G., Mbegbu, M., Kyman, S., & Harris, R. B. (2022). Helicobacter pylori in Native Americans in Northern Arizona †. Diseases, 10(Issue 2). doi:10.3390/diseases10020019
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  Background: In Arizona Helicobacter pylori prevalence of infection among Navajo adults is about 62% and gastric cancer incidence rate is 3–4 times higher than that of the non-Hispanic White population. Aim: The aim of this study was to estimate the prevalence of specific H. pylori virulence factors (cagA and vacA) among Navajo patients undergoing and their association with gastric disease. Methods: Virulence genes, cagA and vacA, in H. pylori were investigated in gastric biopsies from 96 Navajo patients over age 18 who were undergoing esophagogastroduodenoscopy. Biopsies from the antrum and fundus were used for molecular characterization to determine cagA type and number of EPIYA motifs and presence of alleles in the signal (s) and medium (m) regions of the vacA gene. Results: H. pylori infection was found in 22.9% of the biopsy samples. The cagA gene amplified in 57.6% of samples and showed a predominant “Western cagA” type, with the EPIYA-ABC motif (45.4%), most prevalent. The vacA allele s1bm1 was the most prevalent (54.5%). Conclusions: H. pylori genotypes were predominantly cagA Western-type and ABC EPIYA motifs. The vacA s1bm1 genotype was the most prevalent and seemed to be associated with gastritis. American Indian/Alaska Native populations are at higher risk for gastric cancer. It is important to identify genotypes of H. pylori and virulence factors involved in the high prevalence of H. pylori and associated disease among the Navajo population.
• Moore, T. C., & Brown, H. E. (2022). Estimating Aedes aegypti (Diptera: Culicidae) Flight Distance: Meta-Data Analysis. Journal of Medical Entomology, 59(4), 1164-1170.
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  The yellow fever mosquito, Aedes aegypti, is a growing global concern. An ecological parameter necessary for vector control is the dispersal, or flight range, of mosquito vectors. Information on mosquito dispersal supports identifying optimal sampling and control strategies to limit the invasion of adult mosquitoes. Attempts around the world to understand the movement and flight range of Ae. aegypti have used a variety of techniques, but there has been little agreement regarding flight distances of Ae. aegypti, specifically the average linear distance Ae. aegypti travel in their natural environment. To generate a more robust estimate of Ae. aegypti flight distance, we conducted a meta-data analysis with the aims 1) to provide a flight distance measurement and 2) investigate how mosquito flight range can be affected by study design and climatic factors. Published studies were retrieved from public databases and reviewed for mean distance traveled (MDT) or maximum distance traveled measurements of Ae. aegypti. Linear regression was used to assess potential relationships between Ae. aegypti flight distance and factors pertaining to climate, degrees of urbanization, and study design. MDT estimates were pooled from 27 experiments to calculate a weighted MDT of 105.69 m. This study addresses the average flight distance of Ae. aegypti with the intention of informing vector control programs in Ae. aegypti prevalent regions of the world.
• Rowitt, J., & Brown, H. (2022). Disaster event effects on cat and dog populations within United States animal care facility services: A cross sectional study. PLOS Climate, 1(8). doi:10.1371/journal.pclm.0000066
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  It is unclear how disaster events, which are expected to increase due to climate change, will affect animal care services. Understanding the impacts they have on cat and dog populations, and how to integrate animal welfare into disaster preparedness, can facilitate disaster response and improve population health outcomes. Federal Emergency Management (FEMA) disaster data were merged with shelter intake data from SAC (Shelter Animals Count) to compare total number of animals and total number of animals euthanized the month of disaster to the subsequent month and to the same month in the subsequent year. Analyses were stratified by animal (dog /cat), disaster (hurricane/fire), and animal care service type and compared using Wilcoxon Signed Rank test. On average, government animal services (GAS) in counties experiencing a hurricane report an increase in dogs in the facility the month (p
• Sheng, Z. Y., Li, M., Yang, R., Liu, Y. H., Yin, X. X., Mao, J. R., Brown, H. E., An, J., Zhou, H. N., & Wang, P. G. (2022). COVID-19 prevention measures reduce dengue spread in Yunnan Province, China, but do not reduce established outbreak. Emerging Microbes and Infections, 11(Issue 1). doi:10.1080/22221751.2021.2022438
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  The COVID-19 pandemic and measures against it provided a unique opportunity to understand the transmission of other infectious diseases and to evaluate the efficacy of COVID-19 prevention measures on them. Here we show a dengue epidemic in Yunnan, China, during the pandemic of COVID-19 was dramatically reduced compared to non-pandemic years and, importantly, spread was confined to only one city, Ruili. Three key features characterized this dengue outbreak: (i) the urban-to-suburban spread was efficiently blocked; (ii) the scale of epidemic in urban region was less affected; (iii) co-circulation of multiple strains was attenuated. These results suggested that countermeasures taken during COVID-19 pandemic are efficient to prevent dengue transmission between cities and from urban to suburban, as well to reduce the co-circulation of multiple serotypes or genotypes. Nevertheless, as revealed by the spatial analysis, once the dengue outbreak was established, its distribution was very stable and resistant to measures against COVID-19, implying the possibility to develop a precise prediction method.
• Sheng, Z. Y., Li, M., Yang, R., Liu, Y. H., Yin, X. X., Mao, J. R., Brown, H. E., An, J., Zhou, H. N., & Wang, P. G. (2022). COVID-19 prevention measures reduce dengue spread in Yunnan Province, China, but do not reduce established outbreak. Emerging microbes & infections, 11(1), 240-249.
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  The COVID-19 pandemic and measures against it provided a unique opportunity to understand the transmission of other infectious diseases and to evaluate the efficacy of COVID-19 prevention measures on them. Here we show a dengue epidemic in Yunnan, China, during the pandemic of COVID-19 was dramatically reduced compared to non-pandemic years and, importantly, spread was confined to only one city, Ruili. Three key features characterized this dengue outbreak: (i) the urban-to-suburban spread was efficiently blocked; (ii) the scale of epidemic in urban region was less affected; (iii) co-circulation of multiple strains was attenuated. These results suggested that countermeasures taken during COVID-19 pandemic are efficient to prevent dengue transmission between cities and from urban to suburban, as well to reduce the co-circulation of multiple serotypes or genotypes. Nevertheless, as revealed by the spatial analysis, once the dengue outbreak was established, its distribution was very stable and resistant to measures against COVID-19, implying the possibility to develop a precise prediction method.
• Austhof, E., & Brown, H. E. (2021). Flexibility and partnerships perceived as supportive of dual hazard response: COVID-19 and heat related illness, Summer 2020. Journal of Climate Change and Health, 4. doi:10.1016/j.joclim.2021.100068
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  Objectives: To understand how health departments implemented the response to the dual hazards of Heat Related Illness (HRI) and COVID-19 in Summer 2020. Methods: We interviewed five health jurisdictions with a Building Resilience Against Climate Effects (BRACE) Framework HRI project to understand impacts to organizational roles and preparedness activities, capacity to respond to the heat season, challenges experienced with resources and personnel, and how partners influenced their capacity to respond to dual hazards. Results: Health jurisdictions working in both heat preparedness and on the COVID-19 response highlighted three components as integral to maintaining public health capacity throughout the pandemic: 1) adapting to changing roles and responsibilities, 2) building and strengthening inter-organizational partnerships, and 3) maintaining flexibility through cross-training as themes to maintain the public health capacity throughout the pandemic. Conclusions: With impacts of the changing climate, including resultant extreme events with subsequent public health impacts, simultaneous responses are likely to arise again in the future. Developing cross-training programs, fostering flexibility and adaptability within the workforce, and building and sustaining external partnerships can support health departments anticipating the need to respond to simultaneous public health hazards in the future.
• Austhof, E., & Brown, H. E. (2021). Flexibility and partnerships perceived as supportive of dual hazard response: COVID-19 and heat related illness, Summer 2020. The Journal of Climate Change and Health, 4, 100068.
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  To understand how health departments implemented the response to the dual hazards of Heat Related Illness (HRI) and COVID-19 in Summer 2020.
• Brown, H. E., & Cox, J. (2021). Brown and Cox Respond to "Epidemiologic Methods in Epidemiology Education". American Journal of Epidemiology, 190(2), 317.
• Brown, H. E., & Cox, J. (2021). Brown and Cox Respond to "epidemiologic Methods in Epidemiology Education". American Journal of Epidemiology, 190(Issue 2). doi:10.1093/aje/kwaa180
• Brown, H. E., & Cox, J. (2021). Improving Undergraduate Epidemiology Education: An Example Using Instructional Teams. American Journal of Epidemiology, 190(2), 305-312.
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  Epidemiology is a core component of the undergraduate public health curriculum and a critical component of a healthy community and a comprehensive education. Evidence-based, collaborative instructional practices improve student success, reach diverse student populations, and improve learning outcomes. Here we describe the pedagogical approach of an instructional team with which we observed an 18% greater learning gain (95% confidence interval: 6.5, 29.5; t = -3.08; P = 0.002), based on pre-/posttesting in a large (approximately 120 students) undergraduate course, than with the prior course offering. There were no differences in DEW rates (defined as receiving a grade of D (scoring 60%-69%) or E (scoring
• Brown, H. E., & Cox, J. (2021). Improving Undergraduate Epidemiology Education: An Example Using Instructional Teams. American Journal of Epidemiology, 190(Issue 2). doi:10.1093/aje/kwaa181
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  Epidemiology is a core component of the undergraduate public health curriculum and a critical component of a healthy community and a comprehensive education. Evidence-based, collaborative instructional practices improve student success, reach diverse student populations, and improve learning outcomes. Here we describe the pedagogical approach of an instructional team with which we observed an 18% greater learning gain (95% confidence interval: 6.5, 29.5; t =-3.08; P = 0.002), based on pre-/posttesting in a large (approximately 120 students) undergraduate course, than with the prior course offering. There were no differences in DEW rates (defined as receiving a grade of D (scoring 60%-69%) or E (scoring
• Brown, H. E., Sedda, L., Sumner, C., Stefanakos, E., Ruberto, I., & Roach, M. (2021). Understanding Mosquito Surveillance Data for Analytic Efforts: A Case Study. Journal of Medical Entomology, 58(4), 1619-1625.
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  Mosquito surveillance data can be used for predicting mosquito distribution and dynamics as they relate to human disease. Often these data are collected by independent agencies and aggregated to state and national level portals to characterize broad spatial and temporal dynamics. These larger repositories may also share the data for use in mosquito and/or disease prediction and forecasting models. Assumed, but not always confirmed, is consistency of data across agencies. Subtle differences in reporting may be important for development and the eventual interpretation of predictive models. Using mosquito vector surveillance data from Arizona as a case study, we found differences among agencies in how trapping practices were reported. Inconsistencies in reporting may interfere with quantitative comparisons if the user has only cursory familiarity with mosquito surveillance data. Some inconsistencies can be overcome if they are explicit in the metadata while others may yield biased estimates if they are not changed in how data are recorded. Sharing of metadata and collaboration between modelers and vector control agencies is necessary for improving the quality of the estimations. Efforts to improve sharing, displaying, and comparing vector data from multiple agencies are underway, but existing data must be used with caution.
• Brown, H. E., Sedda, L., Sumner, C., Stefanakos, E., Ruberto, I., & Roach, M. (2021). Understanding Mosquito Surveillance Data for Analytic Efforts: A Case Study. Journal of Medical Entomology, 58(Issue 4). doi:10.1093/jme/tjab018
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  Mosquito surveillance data can be used for predicting mosquito distribution and dynamics as they relate to human disease. Often these data are collected by independent agencies and aggregated to state and national level portals to characterize broad spatial and temporal dynamics. These larger repositories may also share the data for use in mosquito and/or disease prediction and forecasting models. Assumed, but not always confirmed, is consistency of data across agencies. Subtle differences in reporting may be important for development and the eventual interpretation of predictive models. Using mosquito vector surveillance data from Arizona as a case study, we found differences among agencies in how trapping practices were reported. Inconsistencies in reporting may interfere with quantitative comparisons if the user has only cursory familiarity with mosquito surveillance data. Some inconsistencies can be overcome if they are explicit in the metadata while others may yield biased estimates if they are not changed in how data are recorded. Sharing of metadata and collaboration between modelers and vector control agencies is necessary for improving the quality of the estimations. Efforts to improve sharing, displaying, and comparing vector data from multiple agencies are underway, but existing data must be used with caution.
• Bui, D. P., Chandran, S. S., Oren, E., Brown, H. E., Harris, R. B., Knight, G. M., & Grandjean, L. (2021). Community transmission of multidrug-resistant tuberculosis is associated with activity space overlap in Lima, Peru. BMC Infectious Diseases, 21(Issue 1). doi:10.1186/s12879-021-05953-8
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  Background: Transmission of multidrug-resistant tuberculosis (MDRTB) requires spatial proximity between infectious cases and susceptible persons. We assess activity space overlap among MDRTB cases and community controls to identify potential areas of transmission. Methods: We enrolled 35 MDRTB cases and 64 TB-free community controls in Lima, Peru. Cases were whole genome sequenced and strain clustering was used as a proxy for transmission. GPS data were gathered from participants over seven days. Kernel density estimation methods were used to construct activity spaces from GPS locations and the utilization distribution overlap index (UDOI) was used to quantify activity space overlap. Results: Activity spaces of controls (median = 35.6 km2, IQR = 25.1–54) were larger than cases (median = 21.3 km2, IQR = 17.9–48.6) (P = 0.02). Activity space overlap was greatest among genetically clustered cases (mean UDOI = 0.63, sd = 0.67) and lowest between cases and controls (mean UDOI = 0.13, sd = 0.28). UDOI was positively associated with genetic similarity of MDRTB strains between case pairs (P < 0.001). The odds of two cases being genetically clustered increased by 22% per 0.10 increase in UDOI (OR = 1.22, CI = 1.09–1.36, P < 0.001). Conclusions: Activity space overlap is associated with MDRTB clustering. MDRTB transmission may be occurring in small, overlapping activity spaces in community settings. GPS studies may be useful in identifying new areas of MDRTB transmission.
• Bui, D. P., Chandran, S. S., Oren, E., Brown, H. E., Harris, R. B., Knight, G. M., & Grandjean, L. (2021). Community transmission of multidrug-resistant tuberculosis is associated with activity space overlap in Lima, Peru. BMC infectious diseases, 21(1), 275.
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  Transmission of multidrug-resistant tuberculosis (MDRTB) requires spatial proximity between infectious cases and susceptible persons. We assess activity space overlap among MDRTB cases and community controls to identify potential areas of transmission.
• Chakravarti, I., Miranda-Schaeubinger, M., Ruiz-Remigio, A., Briones-Garduño, C., Fernández-Figueroa, E. A., Villanueva-Cabello, C. C., Borge-Villareal, A., Bejar-Ramírez, Y., Pérez-González, A., Rivera-Benitez, C., Oren, E., Brown, H. E., Becker, I., & Gilman, R. H. (2022). Chagas Disease in Pregnant Women from Endemic Regions Attending the Hospital General de Mexico, Mexico City. Tropical Medicine and Infectious Disease, 7(1).
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  infection leads to Chagas disease (CD), a neglected tropical infection of significant public health importance in South and Central America and other, non-endemic, countries. Pregnant women and their children are of particular importance to screen as can be transmitted vertically. The objective of this study was to screen for infection among pregnant women from endemic areas seen at the Hospital General de Mexico for prenatal care, so that they and their children may be quickly connected to CD treatment. Pregnant women were recruited through the hospital prenatal clinic and screened for infection using a series of serological and molecular tests. Of 150 screened patients, mean age 26.8 (SD 6.4), 30 (20.0%) were positive by at least one diagnostic test. Of these, only nine (6%) were positive as determined by PCR. Diagnosis of chronic CD is difficult in endemic places like Mexico due to the limitations of current commercially available diagnostic tests. Further evaluation of diagnostic performance of various assays could improve current CD diagnostic algorithms and proper care management in these regions. Genetic variability in the parasite may also play a role in the differing assay performances seen in this study, and this may be a valuable avenue of further research.
• Harris, R. B., Brown, H. E., Begay, R. L., Sanderson, P. R., Chief, C., Monroy, F. P., & Oren, E. (2022). Prevalence and Risk Factors in Three Rural Indigenous Communities of Northern Arizona. International journal of environmental research and public health, 19(2).
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  () is one of the most common bacterial stomach infections and is implicated in a majority of non-cardia gastric cancer. While gastric cancer has decreased in the United States (US), the incidence in the Navajo Nation is nearly four times higher than surrounding Non-Hispanic White populations. Little is known about prevalence in this population or other Indigenous communities in the lower 48 states. In this cross-sectional study, 101 adults representing 73 households from three Navajo Nation chapter communities completed surveys and a urea breath test for active . Accounting for intrahousehold correlation, prevalence was 56.4% (95% CI, 45.4-66.8) and 72% of households had at least one infected person. The odds of having an active infection in households using unregulated water were 8.85 (95% CI, 1.50-53.38) that of the use of regulated water, and males had 3.26 (95% CI, 1.05-10.07) higher odds than female. The prevalence of in Navajo is similar to that seen in Alaska Natives. Further investigation into factors associated with prevention of infection is needed as well as understanding barriers to screening and treatment.
• Langston, M. E., Brown, H. E., Lynch, C. F., Roe, D. J., & Dennis, L. K. (2022). Ambient UVR and Environmental Arsenic Exposure in Relation to Cutaneous Melanoma in Iowa. International journal of environmental research and public health, 19(3).
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  Intermittent sun exposure is the major environmental risk factor for cutaneous melanoma (CM). Cumulative sun exposure and other environmental agents, such as environmental arsenic exposure, have not shown consistent associations. Ambient ultraviolet radiation (UVR) was used to measure individual total sun exposure as this is thought to be less prone to misclassification and recall bias. Data were analyzed from 1096 CM cases and 1033 controls in the Iowa Study of Skin Cancer and Its Causes, a population-based, case-control study. Self-reported residential histories were linked to satellite-derived ambient UVR, spatially derived environmental soil arsenic concentration, and drinking water arsenic concentrations. In men and women, ambient UVR during childhood and adolescence was not associated with CM but was positively associated during adulthood. Lifetime ambient UVR was positively associated with CM in men (OR for highest vs. lowest quartile: 6.09, 95% confidence interval (CI) 2.21-16.8), but this association was not as strong among women (OR for highest vs. lowest quartile: 2.15, 95% CI 0.84-5.54). No association was detected for environmental soil or drinking water arsenic concentrations and CM. Our findings suggest that lifetime and adulthood sun exposures may be important risk factors for CM.
• Tang, X., Sedda, L., & Brown, H. E. (2021). Predicting eastern equine encephalitis spread in North America: An ecological study. Current research in parasitology & vector-borne diseases, 1, 100064.
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  Eastern equine encephalitis (EEE) is a rare but lethal mosquito-borne zoonotic disease. Recent years have seen incursion into new areas of the USA, and in 2019 the highest number of human cases in decades. Due to the low detection rate of EEE, previous studies were unable to quantify large-scale and recent EEE ecological dynamics. We used Bayesian spatial generalized-linear mixed model to quantify the spatiotemporal dynamics of human EEE incidence in the northeastern USA. In addition, we assessed whether equine EEE incidence has predictive power for human cases, independently from other environmental variables. The predictors of the model were selected based on variable importance. Human incidence increased with temperature seasonality, but decreased with summer temperature, summer, fall, and winter precipitation. We also found EEE transmission in equines strongly associated with human infection (OR: 1.57; 95% CI: 1.52-1.60) and latitudes above 41.9°N after 2018. The study designed for sparse dataset described new and known relationships between human and animal EEE and environmental factors, including geographical directionality. Future models must include equine cases as a risk factor when predicting human EEE risks. Future work is still necessary to ascertain the establishment of EEE in northern latitudes and the robustness of the available data.
• Austhof, E., Berisha, V., McMahan, B., Owen, G., Keith, L., Roach, M., & Brown, H. E. (2020). Engaging public health stakeholders in climate and health adaptation. Atmosphere, 11(3), 265. doi:https://doi.org/10.3390/atmos11030265
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  Stakeholder participation at the intersection of climate and health is essential to assess and plan for the human health impacts of current and projected climate-sensitive hazards. Using the Maricopa County Department of Public Health (MCDPH) Coalition on Climate Change and Public Health workgroup and the Climate Assessment for the Southwest (CLIMAS) program as examples, this paper describes the important role of scientist–public health stakeholder collaboratives in addressing the public health impacts of climate-sensitive hazards. Using the MCDPH and CLIMAS stakeholder groups, stakeholder connections were mapped to show relationships between the organization types and connections between scientists and public health stakeholders. Stakeholders, defined as meeting attendees, were primarily individuals from academic institutions (n = 175), government agencies (n = 114), non-profits (n = 90), and health departments (n = 85). Engaging public health stakeholders in transdisciplinary regional climate initiatives and addressing gaps in their networks helped these programs to develop more collaborative projects over time.
• Baum, C., Soliman, A. S., Brown, H. E., Seifeldin, I. A., Ramadan, M., Lott, B., Nguyen, A., El-Ghawalby, A., & Hablas, A. (2020). Regional Variation of Pancreatic Cancer Incidence in the Nile Delta Region of Egypt over a Twelve-Year Period. Journal of Cancer Epidemiology, 2020, 6031708.
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  Pancreatic cancer is one of the deadliest forms of cancer, with incidence rates rising in many countries around the world. Geographic variation in pancreatic cancer incidence has not been studied extensively, especially in low- and middle-income countries. The aim of this study was to characterize the distribution of pancreatic cancer incidence in the central Nile Delta region of Egypt and to examine differences by urban and rural patient residence using the nation's only population-based cancer registry.
• Cook, A., Harris, R., Brown, H. E., & Bedrick, E. (2020). Geospatial characteristics of non-motor vehicle and assault-related trauma events in greater Phoenix, Arizona. Injury Epidemiology, 7(Issue 1). doi:10.1186/s40621-020-00258-x
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  Background: Injury-causing events are not randomly distributed across a landscape, but how they are associated with the features and characteristics of the places where they occur in Arizona (AZ) remains understudied. Clustering of trauma events and associations with areal sociodemographic characteristics in the greater Phoenix (PHX), AZ region can promote understanding and inform efforts to ameliorate a leading cause of death and disability for Arizonans. The outcomes of interest are trauma events unrelated to motor vehicle crashes (MVC) and the subgroup of trauma events due to interpersonal assaults. Methods: A retrospective, ecological study was performed incorporating data from state and national sources for the years 2013-2017. Geographically weighted regression models explored associations between the rates of non-MVC trauma events (n/10,000 population) and the subgroup of assaultive trauma events per 1000 and areal characteristics of socioeconomic deprivation (areal deprivation index [ADI]), the density of retail alcohol outlets for offsite consumption, while controlling for race/ethnicity, population density, and the percentage urban population. Results: The 63,451 non-MVC traumas within a 3761 mile2 study area encompassing PHX and 22 surrounding communities, an area with nearly 60% of the state's population and 54% of the trauma events in the AZ State Trauma Registry for the years 2013-2017. Adjusting for confounders, ADI was associated with the rates of non-MVC and assaultive traumas in all census block groups studied (mean coefficients 0.05 sd. 0.001 and 0.07 sd. 0.002 for non-MVC and assaultive trauma, respectively). Alcohol retail outlet density was also associated with non-MVC and assaultive traumas in fewer block groups compared to ADI. Conclusion: Socioeconomic deprivation and alcohol outlet density were associated with injury producing events in the greater PHX area. These features persist in the environment before and after the traumas occur. Ongoing research is warranted to identify the most influential areal predictors of traumatic injury-causing events in the greater PHX area to inform and geographically target prevention initiatives.
• Cook, A., Harris, R., Brown, H. E., & Bedrick, E. (2020). Geospatial characteristics of non-motor vehicle and assault-related trauma events in greater Phoenix, Arizona. Injury epidemiology, 7(1), 34.
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  Injury-causing events are not randomly distributed across a landscape, but how they are associated with the features and characteristics of the places where they occur in Arizona (AZ) remains understudied. Clustering of trauma events and associations with areal sociodemographic characteristics in the greater Phoenix (PHX), AZ region can promote understanding and inform efforts to ameliorate a leading cause of death and disability for Arizonans. The outcomes of interest are trauma events unrelated to motor vehicle crashes (MVC) and the subgroup of trauma events due to interpersonal assaults.
• Harris, R. B., Sanderson, P. R., Monroy, F. P., Mbegbu, M., Kyman, S., Jarrin, G., Harris, R. B., Chief, C., & Brown, H. E. (2020). Abstract PO-162: Helicobacter pylori in Native Americans in Northern Arizona. Cancer Epidemiology, Biomarkers & Prevention. doi:10.1158/1538-7755.disp20-po-162
• Harris, R. B., Sanderson, P. R., Oren, E., Monroy, F. P., Harris, R. B., Chief, C., Brown, H. E., & Begay, R. (2020). Abstract D109:Helicobacter pyloriinfections in Navajo communities of Northern Arizona. Cancer Epidemiology, Biomarkers & Prevention. doi:10.1158/1538-7755.disp19-d109
• Lega, J. C., Brown, H. E., & Barrera, R. (2020). A 70 percent reduction in mosquito populations does not require removal of 70 percent of mosquitoes. Journal of Medical Entomology, 57(5), 1668-1670.
• Lega, J., Brown, H. E., & Barrera, R. (2020). A 70% reduction in mosquito populations does not require removal of 70% of mosquitoes. Journal of Medical Entomology, 57(Issue 5). doi:10.1093/jme/tjaa066
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  We added a vector control component to our existing abundance model to simulate intensive vector control in Puerto Rico. Removing 20-30% of gravid females in the model matches observed 60-80% reductions. The model's capacity to reproduce vector control increases its utility for planning and evaluation strategies.
• Zhu, G., Yuan, L., Xu, B., Xiao, X., Vandewoude, S., Shi, Z., Shi, X., Shi, J., Olival, K. J., Martinez-lopez, B., Lu, J., Liu, W., Liu, Q., Lips, K. R., Li, H., Grohn, Y. T., Getz, W. M., Evans, T. S., Escobar, L. E., , Civitello, D. J., et al. (2020). Synergistic China-US Ecological Research is Essential for Global Emerging Infectious Disease Preparedness.. EcoHealth, 17(1), 160-173. doi:10.1007/s10393-020-01471-2
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  The risk of a zoonotic pandemic disease threatens hundreds of millions of people. Emerging infectious diseases also threaten livestock and wildlife populations around the world and can lead to devastating economic damages. China and the USA-due to their unparalleled resources, widespread engagement in activities driving emerging infectious diseases and national as well as geopolitical imperatives to contribute to global health security-play an essential role in our understanding of pandemic threats. Critical to efforts to mitigate risk is building upon existing investments in global capacity to develop training and research focused on the ecological factors driving infectious disease spillover from animals to humans. International cooperation, particularly between China and the USA, is essential to fully engage the resources and scientific strengths necessary to add this ecological emphasis to the pandemic preparedness strategy. Here, we review the world's current state of emerging infectious disease preparedness, the ecological and evolutionary knowledge needed to anticipate disease emergence, the roles that China and the USA currently play as sources and solutions to mitigating risk, and the next steps needed to better protect the global community from zoonotic disease.
• Dennis, L. K., Brown, H. E., & Farland, L. V. (2019). DSM II Colormeter for measuring skin color: its usefulness and reliability of its measurement of melanin. J Dermatol Cosmet Treat, 1(1), 1-5.
• Florea, A., Brown, H. E., Harris, R. B., & Oren, E. (2019). Ethnic Disparities in Gastric Cancer Presentation and Screening Practice in the United States: Analysis of 1997-2010 Surveillance, Epidemiology, and End Results-Medicare Data. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 28(4), 659-665.
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  Chronic infection with () is the strongest risk factor for distal gastric cancer. Although gastric cancer incidence has decreased, variation by race and ethnicity is observed. This study describes gastric cancer presentation and screening services among Medicare patients by race/ethnicity, place of birth, and history of gastric cancer-related conditions.
• Florea, A., Brown, H. E., Harris, R. B., & Oren, E. (2019). Ethnic disparities in gastric cancer presentation and screening practice in the United States: Analysis of 1997–2010 surveillance, epidemiology, and end results-Medicare data. Cancer Epidemiology Biomarkers and Prevention, 28(Issue 4). doi:10.1158/1055-9965.epi-18-0471
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  Background: Chronic infection with Helicobacter pylori with non-Hispanic whites (NHW), Hispanics, and blacks (H. pylori) is the strongest risk factor for distal gastric cancer. (with 64.4%, 33.9%, and 72.9% U.S.-born, respectively). Although gastric cancer incidence has decreased, variation by For NHWs, the most frequently diagnosed gastric cancer site race and ethnicity is observed. This study describes gastric was the cardia (35.6%) compared with
• Harris, R. B., Roe, D. J., Oren, E., Knight, G. M., Harris, R. B., Grandjean, L., Gilman, R. H., Bui, D. P., & Brown, H. E. (2019). A Case-Control Study to Identify Community Venues Associated with Genetically-clustered, Multidrug-resistant Tuberculosis Disease in Lima, Peru.. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 68(9), 1547-1555. doi:10.1093/cid/ciy746
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  The majority of tuberculosis transmission occurs in community settings. Our primary aim in this study was to assess the association between exposure to community venues and multidrug-resistant (MDR) tuberculosis. Our secondary aim was to describe the social networks of MDR tuberculosis cases and controls..We recruited laboratory-confirmed MDR tuberculosis cases and community controls that were matched on age and sex. Whole-genome sequencing was used to identify genetically clustered cases. Venue tracing interviews (nonblinded) were conducted to enumerate community venues frequented by participants. Logistic regression was used to assess the association between MDR tuberculosis and person-time spent in community venues. A location-based social network was constructed, with respondents connected if they reported frequenting the same venue, and an exponential random graph model (ERGM) was fitted to model the network..We enrolled 59 cases and 65 controls. Participants reported 729 unique venues. The mean number of venues reported was similar in both groups (P = .92). Person-time in healthcare venues (adjusted odds ratio [aOR] = 1.67, P = .01), schools (aOR = 1.53, P < .01), and transportation venues (aOR = 1.25, P = .03) was associated with MDR tuberculosis. Healthcare venues, markets, cinemas, and transportation venues were commonly shared among clustered cases. The ERGM indicated significant community segregation between cases and controls. Case networks were more densely connected..Exposure to healthcare venues, schools, and transportation venues was associated with MDR tuberculosis. Intervention across the segregated network of case venues may be necessary to effectively stem transmission.
• Isoe, J., Koch, L. E., Isoe, Y. E., Rascón, A. A., Brown, H. E., Massani, B. B., & Miesfeld, R. L. (2019). Identification and characterization of a mosquito-specific eggshell organizing factor in Aedes aegypti mosquitoes. PLoS Biology, 17(1), e3000068.
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  Mosquito-borne diseases are responsible for several million human deaths annually around the world. One approach to controlling mosquito populations is to disrupt molecular processes or antagonize novel metabolic targets required for the production of viable eggs. To this end, we focused our efforts on identifying proteins required for completion of embryonic development that are mosquito selective and represent potential targets for vector control. We performed bioinformatic analyses to identify putative protein-coding sequences that are specific to mosquito genomes. Systematic RNA interference (RNAi) screening of 40 mosquito-specific genes was performed by injecting double-stranded RNA (dsRNA) into female Aedes aegypti mosquitoes. This experimental approach led to the identification of eggshell organizing factor 1 (EOF1, AAEL012336), which plays an essential role in the formation and melanization of the eggshell. Eggs deposited by EOF1-deficient mosquitoes have nonmelanized fragile eggshells, and all embryos are nonviable. Scanning electron microscopy (SEM) analysis identified that exochorionic eggshell structures are strongly affected in EOF1-deficient mosquitoes. EOF1 is a potential novel target, to our knowledge, for exploring the identification and development of mosquito-selective and biosafe small-molecule inhibitors.
• Isoe, J., Koch, L. E., Isoe, Y. E., Rascón, A. A., Brown, H. E., Massani, B. B., & Miesfeld, R. L. (2019). Identification and characterization of a mosquito-specific eggshell organizing factor in Aedes aegypti mosquitoes. PLoS Biology, 17(Issue 1). doi:10.1371/journal.pbio.3000068
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  Mosquito-borne diseases are responsible for several million human deaths annually around the world. One approach to controlling mosquito populations is to disrupt molecular processes or antagonize novel metabolic targets required for the production of viable eggs. To this end, we focused our efforts on identifying proteins required for completion of embryonic development that are mosquito selective and represent potential targets for vector control. We performed bioinformatic analyses to identify putative protein-coding sequences that are specific to mosquito genomes. Systematic RNA interference (RNAi) screening of 40 mosquito-specific genes was performed by injecting double-stranded RNA (dsRNA) into female Aedes aegypti mosquitoes. This experimental approach led to the identification of eggshell organizing factor 1 (EOF1, AAEL012336), which plays an essential role in the formation and melanization of the eggshell. Eggs deposited by EOF1-deficient mosquitoes have nonmelanized fragile eggshells, and all embryos are nonviable. Scanning electron microscopy (SEM) analysis identified that exochorionic eggshell structures are strongly affected in EOF1-deficient mosquitoes. EOF1 is a potential novel target, to our knowledge, for exploring the identification and development of mosquito-selective and biosafe small-molecule inhibitors.
• Luz, P. M., Brown, H. E., & Struchiner, C. J. (2019). Disgust as an emotional driver of vaccine attitudes and uptake? A mediation analysis. Epidemiology and Infection, 147(Issue). doi:10.1017/s0950268819000517
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  Research on the drivers of vaccine acceptance has expanded but most interventions fall short of coverage targets. We explored whether vaccine uptake is driven directly or indirectly by disgust with attitudes towards vaccines acting as a possible mediator. An online cross-sectional study of 1007 adults of the USA via Amazon’s Mechanical Turk was conducted in January 2017. The questionnaire consisted of four sections: (1) items assessing attitudes towards vaccines and vaccine uptake, (2) revised Disgust Scale (DS-R) to measure Disgust Sensitivity, (3) Perceived Vulnerability to Disease scale (PVD) to measure Germ Aversion and Perceived Susceptibility, and (4) socio-demographic information. Using mediation analysis, we assess the direct, the indirect (through Vaccine Attitudes) and the total effect of Disgust Sensitivity, Germ Aversion and Perceived Susceptibility on 2016 self-reported flu vaccine uptake. Mediation analysis showed the effect of Disgust Sensitivity and Germ Aversion on vaccine uptake to be twofold: a direct positive effect on vaccine uptake and an indirect negative effect through Vaccine Attitudes. In contrast, Perceived Susceptibility was found to have only a direct positive effect on vaccine uptake. Nonetheless, these effects were attenuated and small compared to economic, logistic and psychological determinants of vaccine uptake.
• Luz, P., Brown, H. E., & Struchiner, C. (2019). Disgust as an emotional driver of vaccine attitudes and uptake? A mediation analysis. Epidemiology and Infection, 147(e182), 1-8.
• Oren, E., Pelley, E., Purve, J., Lauro, P. L., Dennis, L. K., & Brown, H. E. (2019). Emerging evidence for infectious causes of cancer in the United States.. Epidemiologic Reviews.
• Thompson, C. A., Saxberg, K., Lega, J., Tong, D., & Brown, H. E. (2019). A cumulative gravity model for inter-urban spatial interaction at different scales. Journal of Transport Geography, 79(Issue). doi:10.1016/j.jtrangeo.2019.102461
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  The classical gravity model assumes the knowledge of origin-destination (OD) flows between places. While this is reasonable for some modes of transportation such as air travel, it presents challenges to many other applications such as road travel where the observed flow on road segments, such as annual average daily traffic (AADT), may involve traffic for multiple OD pairs. This article introduces a methodology to calibrate a cumulative gravity model on a scale-specific road network. The model infers the traffic on OD pairs from the knowledge of link flows and we document its effectiveness in predicting the bidirectional volume of traffic on highways in the United States. Census data and state AADT were used to calibrate both the noncumulative and cumulative gravity models in three different regions in the western US: Arizona only, 10 western US states, and 16 western US states. The road networks were built by defining nodes as population centers of >10,000 inhabitants for Arizona and >500,000 for the other two networks. A systematic method to remove junction nodes that do not satisfy population threshold requirements but are necessary to maintain network connectivity is presented. The cumulative gravity model performed better (with a R-squared value of 0.93 in Arizona) than the standard model, but the improvement, based on two goodness-of-fit metrics (Common Part of Commuters and least squares) was above 2% only in the Arizona network. Removal of commercial traffic from the data further improved the model's calibration in the 10-state network. A thresholding method that connects the cumulative to the standard gravity model reveals that most road trips in Arizona are within the 150-mile range and that this distance increases to 500 miles in both western networks. Potential future applications of the present work are discussed.
• Thompson, C., Saxberg, K., Lega, J. C., Tong, D., & Brown, H. E. (2019). A new gravity model for spatial interaction. Journal of Transport Geography, 79.
• Brown, H., Smith, C., Lashway, S., & Lysyk, T. (2018). Influence of the Length of Storage on Aedes aegypti (Diptera: Culicidae) Egg Viability. Journal of Medical Entomology, 54(2). doi:10.1093/jme/tjw186
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  Aedes aegypti (L.) is one of the most important arboviral vectors worldwide. Vector control is targeted at immature and adult stages; however, eggs are resistant to desiccation and may repopulate treated areas long after treatment ceases. We investigated the effect of age on Ae. aegypti egg hatching rates using newly colonized populations (F2) from an arid region. We found a strongly negative association where older eggs had lower hatch rates. The capacity of eggs to survive for long periods of time has implications on mosquito control. In addition, the accumulation of eggs in containers should be accounted for in abundance modeling efforts where populations may grow rapidly early in the season.
• Del Valle, S. Y., McMahon, B. H., Asher, J., Hatchett, R., Lega, J. C., Brown, H. E., Leany, M. E., Pantazis, Y., Roberts, D. J., Moore, S., Peterson, A. T., Escobar, L. E., Qiao, H., Hengartner, N. W., & Mukundan, H. (2018). Summary results of the 2014-2015 DARPA Chikungunya challenge. BMC Infectious Diseases, 18(Issue 1). doi:10.1186/s12879-018-3124-7
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  Background: Emerging pathogens such as Zika, chikungunya, Ebola, and dengue viruses are serious threats to national and global health security. Accurate forecasts of emerging epidemics and their severity are critical to minimizing subsequent mortality, morbidity, and economic loss. The recent introduction of chikungunya and Zika virus to the Americas underscores the need for better methods for disease surveillance and forecasting. Methods: To explore the suitability of current approaches to forecasting emerging diseases, the Defense Advanced Research Projects Agency (DARPA) launched the 2014-2015 DARPA Chikungunya Challenge to forecast the number of cases and spread of chikungunya disease in the Americas. Challenge participants (n=38 during final evaluation) provided predictions of chikungunya epidemics across the Americas for a six-month period, from September 1, 2014 to February 16, 2015, to be evaluated by comparison with incidence data reported to the Pan American Health Organization (PAHO). This manuscript presents an overview of the challenge and a summary of the approaches used by the winners. Results: Participant submissions were evaluated by a team of non-competing government subject matter experts based on numerical accuracy and methodology. Although this manuscript does not include in-depth analyses of the results, cursory analyses suggest that simpler models appear to outperform more complex approaches that included, for example, demographic information and transportation dynamics, due to the reporting biases, which can be implicitly captured in statistical models. Mosquito-dynamics, population specific information, and dengue-specific information correlated best with prediction accuracy. Conclusion: We conclude that with careful consideration and understanding of the relative advantages and disadvantages of particular methods, implementation of an effective prediction system is feasible. However, there is a need to improve the quality of the data in order to more accurately predict the course of epidemics.
• Del Valle, S. Y., McMahon, B. H., Asher, J., Hatchett, R., Lega, J. C., Brown, H. E., Leany, M. E., Pantazis, Y., Roberts, D., Moore, S., Peterson, T., Escobar, L. E., Qiao, H., Hengartner, N. W., & Mukundan, H. (2018). Summary Results of the 2014-2015 DARPA Chikungunya Challenge. BMC Infectious Diseases, 18, 245. doi:http://dx.doi.org/10.1186/s12879-018-3124-7
• Langston, M. E., Dennis, L. K., Lynch, C. F., Roe, D., & Brown, H. E. (2017). Temporal Trends in Satellite-Derived Erythemal UVB and Implications for Ambient Sun Exposure Assessment. Int J Environ Res Public Health.
• Roach, M., Austhof, E., Berisha, V., Brown, H. E., Carr, D., Harlow-Smith, L., Hondula, D. M., & Snyder, K. (2018). Addendum to the Arizona Climate and Health Adaptation Plan. Report.
• Brown, H. E., Barrera, R., Comrie, A. C., & Lega, J. (2017). Effect of Temperature Thresholds on Modeled Aedes aegypti (Diptera: Culicidae) population dynamics. Journal of Medical Entomology, 54(Issue 4). doi:10.1093/jme/tjx041
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  Dynamic simulation models provide vector abundance estimates using only meteorological data. However, model outcomes may heavily depend on the assumptions used to parameterize them. We conducted a sensitivity analysis for a model of Aedes aegypti (L.) abundance using weather data from two locations where this vector is established, La Margarita, Puerto Rico and Tucson, Arizona. We tested the effect of simplifying temperature-dependent development and mortality rates and of changing development and mortality thresholds as compared with baselines estimated using biophysical models. The simplified development and mortality rates had limited effect on abundance estimates in either location. However, in Tucson, where the vector is established but has not transmitted viruses, a difference of 5 °C resulted in populations either surviving or collapsing in the hot Arizona mid-summer, depending on the temperature thresholds. We find three important implications of the observed sensitivity to temperature thresholds. First, this analysis indicates the need for better estimates of the temperature tolerance thresholds to refine entomologic risk mapping for disease vectors. Second, our results highlight the importance of extreme temperatures on vector survival at the marginal areas of this vector's distribution. Finally, the model suggests that adaptation to warmer temperatures may shift regions of pathogen transmission.
• Brown, H. E., Barrera, R., Comrie, A. C., & Lega, J. (2017). Effect of temperature thresholds on modeled Aedes aegypti (Diptera: Culicidae) population dynamics. Journal of Medical Entomology, 54(4), 869-877.
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  Dynamic simulation models provide vector abundance estimates using only meteorological data. However, model outcomes may heavily depend on the assumptions used to parameterize them. We conducted a sensitivity analysis for a model of Aedes aegypti (L.) abundance using weather data from two locations where this vector is established, La Margarita, Puerto Rico and Tucson, Arizona. We tested the effect of simplifying temperature-dependent development and mortality rates and of changing development and mortality thresholds as compared with baselines estimated using biophysical models. The simplified development and mortality rates had limited effect on abundance estimates in either location. However, in Tucson, where the vector is established but has not transmitted viruses, a difference of 5 °C resulted in populations either surviving or collapsing in the hot Arizona mid-summer, depending on the temperature thresholds. We find three important implications of the observed sensitivity to temperature thresholds. First, this analysis indicates the need for better estimates of the temperature tolerance thresholds to refine entomologic risk mapping for disease vectors. Second, our results highlight the importance of extreme temperatures on vector survival at the marginal areas of this vector's distribution. Finally, the model suggests that adaptation to warmer temperatures may shift regions of pathogen transmission.
• Brown, H. E., Cox, J., Comrie, A. C., & Barrera, R. (2017). Habitat and Density of Oviposition Opportunity Influences Aedes aegypti (Diptera: Culicidae) Flight Distance. Journal of Medical Entomology, 54(5), 1385-1389.
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  Understanding the dispersal of Aedes (aegypti (L.) Diptera: Culicidae) after consuming a potentially infectious bloodmeal is an important part of controlling the spread of the arboviruses it transmits. Because of the impact on abundance, removal of oviposition sites is a key component of vector control. However, source reduction around a case may encourage dispersal of potentially infected vectors. We compare the effect of oviposition site availability on Ae. aegypti dispersal behavior within 30-m linear cages in three model ecosystems at the University of Arizona's Biosphere 2 research facility. We found a significant interaction effect in which, when oviposition site density was sparse, dispersal was greater in the highly vegetated humid rainforest and limited in the low vegetation, arid desert model ecosystem. When oviposition site density was dense, no significant effect on dispersal was observed. These analyses support the idea that source reduction has an important influence on the distance that gravid, potentially infected, females will travel.
• Brown, H. E., Cox, J., Comrie, A. C., & Barrera, R. (2017). Habitat and density of oviposition opportunity influences Aedes aegypti (Diptera: Culicidae) flight distance. Journal of Medical Entomology, 54(Issue 5). doi:10.1093/jme/tjx083
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  Understanding the dispersal of Aedes (aegypti (L.) Diptera: Culicidae) after consuming a potentially infectious bloodmeal is an important part of controlling the spread of the arboviruses it transmits. Because of the impact on abundance, removal of oviposition sites is a key component of vector control. However, source reduction around a case may encourage dispersal of potentially infected vectors. We compare the effect of oviposition site availability on Ae. aegypti dispersal behavior within 30-m linear cages in three model ecosystems at the University of Arizona's Biosphere 2 research facility. We found a significant interaction effect in which, when oviposition site density was sparse, dispersal was greater in the highly vegetated humid rainforest and limited in the low vegetation, arid desert model ecosystem. When oviposition site density was dense, no significant effect on dispersal was observed. These analyses support the idea that source reduction has an important influence on the distance that gravid, potentially infected, females will travel.
• Brown, H. E., Mu, W., Khan, M., Tsang, C., Liu, J., & Tong, D. (2017). Spatial scale in environmental risk mapping: A valley fever case study. Journal of Public Health Research, 6(Issue 2). doi:10.4081/jphr.2017.886
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  Background. Valley fever is a fungal infection occurring in desert regions of the U.S. and Central and South America. Environmental risk mapping for this disease is hampered by challenges with detection, case reporting, and diagnostics as well as challenges common to spatial data handling. Design and Methods. Using 12,349 individual cases in Arizona from 2006 to 2009, we analyzed risk factors at both the individual and area levels. Results. Risk factors including elderly population, income status, soil organic carbon, and density of residential area were found to be positively associated with residence of Valley fever cases. A negative association was observed for distance to desert and pasture/ hay land cover. The association between incidence and two land cover variables (shrub and cultivated crop lands) varied depending on the spatial scale of the analysis. Conclusions. The consistence of age, income, population density, and proximity to natural areas supports that these are important predictors of Valley fever risk. However, the inconsistency of the land cover variables across scales highlights the importance of how scale is treated in risk mapping.
• Driscoll, L. J., Brown, H. E., Harris, R. B., & Oren, E. (2017). Population knowledge, attitude, and practice regarding Helicobacter pylori transmission and outcomes: A Literature Review. Frontiers in Public Health, 5, 144.
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  Helicobacter pylori infection is associated with the development of chronic gastritis, peptic ulcer disease, and gastric cancer. Current clinical recommendations are that H. pylori test-and-treat should be individualized based on comorbidities and patient preferences among populations at increased risk for certain morbidities. However, knowledge, attitudes and practices regarding H. pylori among potential patient populations are largely unknown.
• Heidi E, B., Wangshu, M., Mohammed, K., Clarisse, T., Jian, L., & Daoqin, T. (2017). Spatial scale in environmental risk mapping: A Valley fever case study. Journal of Public Health Research, 6(2), 886.
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  Valley fever is a fungal infection occurring in desert regions of the U.S. and Central and South America. Environmental risk mapping for this disease is hampered by challenges with detection, case reporting, and diagnostics as well as challenges common to spatial data handling.
• Langston, M., Dennis, L., Lynch, C., Roe, D., & Brown, H. (2017). Temporal trends in satellite-derived erythemal UVB and implications for ambient sun exposure assessment. International Journal of Environmental Research and Public Health, 14(Issue 2). doi:10.3390/ijerph14020176
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  Ultraviolet radiation (UVR) has been associated with various health outcomes, including skin cancers, vitamin D insufficiency, and multiple sclerosis. Measurement of UVR has been difficult, traditionally relying on subject recall. We investigated trends in satellite-derived UVB from 1978 to 2014 within the continental United States (US) to inform UVR exposure assessment and determine the potential magnitude of misclassification bias created by ignoring these trends. Monthly UVB data remotely sensed from various NASA satellites were used to investigate changes over time in the United States using linear regression with a harmonic function. Linear regression models for local geographic areas were used to make inferences across the entire study area using a global field significance test. Temporal trends were investigated across all years and separately for each satellite type due to documented differences in UVB estimation. UVB increased from 1978 to 2014 in 48% of local tests. The largest UVB increase was found in Western Nevada (0.145 kJ/m2 per five-year increment), a total 30-year increase of 0.87 kJ/m2. This largest change only represented 17% of total ambient exposure for an average January and 2% of an average July in Western Nevada. The observed trends represent cumulative UVB changes of less than a month, which are not relevant when attempting to estimate human exposure. The observation of small trends should be interpreted with caution due to measurement of satellite parameter inputs (ozone and climatological factors) that may impact derived satellite UVR nearly 20% compared to ground level sources. If the observed trends hold, satellite-derived UVB data may reasonably estimate ambient UVB exposures even for outcomes with long latency phases that predate the satellite record.
• Lega, J., Brown, H. E., & Barrera, R. (2017). Aedes aegypti (Diptera: Culicidae) Abundance Model Improved With Relative Humidity and Precipitation-Driven Egg Hatching. Journal of Medical Entomology, 54(5), 1375-1384.
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  We propose an improved Aedes aegypti (L.) abundance model that takes into account the effect of relative humidity (RH) on adult survival, as well as rainfall-triggered egg hatching. The model uses temperature-dependent development rates described in the literature as well as documented estimates for mosquito survival in environments with high RH, and for egg desiccation. We show that combining the two additional components leads to better agreement with surveillance trap data and with dengue incidence reports in various municipalities of Puerto Rico than incorporating either alone or neither. Capitalizing on the positive association between disease incidence and vector abundance, this improved model is therefore useful to estimate incidence of Ae. aegypti-borne diseases in locations where the vector is abundant year-round.
• Lega, J., Brown, H. E., & Barrera, R. (2017). Aedes aegypti (Diptera: Culicidae) abundance model improved with relative humidity and precipitation-driven egg hatching. Journal of Medical Entomology, 54(Issue 5). doi:10.1093/jme/tjx077
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  We propose an improved Aedes aegypti (L.) abundance model that takes into account the effect of relative humidity (RH) on adult survival, as well as rainfall-triggered egg hatching. The model uses temperaturedependent development rates described in the literature as well as documented estimates for mosquito survival in environments with high RH, and for egg desiccation. We show that combining the two additional components leads to better agreement with surveillance trap data and with dengue incidence reports in various municipalities of Puerto Rico than incorporating either alone or neither. Capitalizing on the positive association between disease incidence and vector abundance, this improved model is therefore useful to estimate incidence of Ae. aegypti-borne diseases in locations where the vector is abundant year-round.
• Luz, P. M., Johnson, R. E., & Brown, H. E. (2017). Workplace availability, risk group and perceived barriers predictive of 2016-17 influenza vaccine uptake in the United States: A cross-sectional study. Vaccine, 35(43), 5890-5896.
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  Seasonal influenza, though mostly self-limited in the healthy adult, may lead to severe disease and/or complications in subpopulations. Annual influenza vaccination is available in many countries with coverage goals rarely being met. We conducted a cross-sectional study of influenza vaccine uptake and explored socio-demographic, economic, and psychological factors that explained vaccine uptake.
• Luz, P. M., Luz, P. M., Johnson, R. E., Johnson, R. E., Brown, H. E., & Brown, H. E. (2017). Workplace availability, risk group and perceived barriers predictive of 2016–17 influenza vaccine uptake in the United States: A cross-sectional study. Vaccine, 35(Issue 43). doi:10.1016/j.vaccine.2017.08.078
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  Background Seasonal influenza, though mostly self-limited in the healthy adult, may lead to severe disease and/or complications in subpopulations. Annual influenza vaccination is available in many countries with coverage goals rarely being met. We conducted a cross-sectional study of influenza vaccine uptake and explored socio-demographic, economic, and psychological factors that explained vaccine uptake. Methods The survey was administered via Amazon Mechanical Turk (MTurk) to United States residents in January 2017, using the Qualtrics platform. Using principal axis factor analysis, we reduced the 25 items theory-based psychological determinants into the primary constructs they measure if/when internal consistency was sufficient (Cronbach's alpha >0.60). Logistic regression models were used to quantify the association of socio-demographic, economic, and psychological factors with reported vaccine behavior in the 2016–17 flu season. Results 1007 participants completed the survey, sex distribution was even, 67% had 25–44 years of age, and 61% annual household income of $30–99 thousand United States dollars. About 25% had the flu shot offered at their workplace and 20% reported belonging to a group for whom the flu shot is recommended. Vaccine uptake was 31.5%. Eight predictors remained in the final adjusted model (R2 = 0.489), having the vaccine offered at the workplace, belonging to a group for whom the vaccine is recommended, and higher perceived barriers were the strongest predictors of vaccine uptake, increasing (and decreasing in the case of barriers) the odds by >3-fold. Additionally, higher household income, higher perceived susceptibility and higher perceived benefits also independently predicted vaccine uptake. Discussion We found evidence that perceived barriers significantly impaired vaccine uptake to the same extent that having the vaccine offered at the workplace or belonging to a group for whom the vaccine is recommended facilitated uptake. Ideally, a better understanding of drivers of vaccine hesitancy will result in improved interventions to increase vaccine uptake.
• Murakami, T. T., Scranton, R., Brown, H. E., Harris, R. B., Chen, Z., Musuku, S., & Oren, E. (2017). Management of Helicobacter Pylori in the United States: Results from a national survey of gastroenterology physicians. Preventive Medicine, 100, 216-222.
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  We sought to determine current knowledge and practices among gastroenterology physicians and assess adherence to current guidelines for H. pylori management.
• Reyes-Castro, P. A., Harris, R. B., Brown, H. E., Christopherson, G. L., & Ernst, K. C. (2017). Spatio-temporal and neighborhood characteristics of two dengue outbreaks in two arid cities of Mexico. Acta Tropica, 167(Issue). doi:10.1016/j.actatropica.2017.01.001
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  Little is currently known about the spatial-temporal dynamics of dengue epidemics in arid areas. This study assesses dengue outbreaks that occurred in two arid cities of Mexico, Hermosillo and Navojoa, located in northern state of Sonora. Laboratory confirmed dengue cases from Hermosillo (N = 2730) and Navojoa (N = 493) were geocoded by residence and assigned neighborhood-level characteristics from the 2010 Mexican census. Kernel density and Space-time cluster analysis was performed to detect high density areas and space-time clusters of dengue. Ordinary Least Square regression was used to assess the changing socioeconomic characteristics of cases over the course of the outbreaks. Both cities exhibited contiguous patterns of space-time clustering. Initial areas of dissemination were characterized in both cities by high population density, high percentage of occupied houses, and lack of healthcare. Future research and control efforts in these regions should consider these space-time and socioeconomic patterns.
• Brown, H. E., Smith, C., & Lashway, S. (2016). Influence of the length of storage on Aedes aegypti (Diptera: Culicidae) egg viability. Journal of Medical Entomology.
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  Aedes aegypti (L.) is one of the most important arboviral vectors worldwide. Vector control is targeted at immature and adult stages; however, eggs are resistant to desiccation and may repopulate treated areas long after treatment ceases. We investigated the effect of age on Ae. aegypti egg hatching rates using newly colonized populations (F2) from an arid region. We found a strongly negative association where older eggs had lower hatch rates. The capacity of eggs to survive for long periods of time has implications on mosquito control. In addition, the accumulation of eggs in containers should be accounted for in abundance modeling efforts where populations may grow rapidly early in the season.
• Bui, D., Brown, H. E., Harris, R. B., & Oren, E. (2016). Serologic Evidence for Fecal-Oral Transmission of Helicobacter pylori. The American Journal of Tropical Medicine and Hygiene, 94(1), 82-8.
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  Helicobacter pylori infection is among the most prevalent infections in the world and a key cause of gastric diseases; however, its route of transmission remains unclear. This study aimed to assess the potential for fecal-oral transmission of H. pylori by leveraging its association with a disease with known etiology. Utilizing serology data from the National Health and Nutrition Examination Survey (NHANES 1999; N = 6,347), the association between H. pylori and hepatitis A virus (HAV), a sensitive indicator for fecal-oral exposure, was assessed. Survey-weighted kappa and multiple logistic regression were used to quantify the association between H. pylori and HAV after controlling for age, sex, race, poverty, birthplace, crowding, smoking, and alcohol use. Concordant serological results were found among 69.8% of participants (survey-weighted κ = 0.30, 95% confidence interval [CI] = 0.26, 0.35). The adjusted odds of H. pylori seropositivity were over two times higher after adjusting for confounders (odds ratio = 2.27, 95% CI = 1.79, 2.87). Results from this study suggest H. pylori and HAV infections are strongly associated. Since HAV is primarily transmitted through the fecal-oral route, fecal-oral transmission may be an important pathway for H. pylori spread.
• Bui, D., Brown, H. E., Harris, R. B., & Oren, E. (2016). Serologic evidence for fecal-oral transmission of helicobacter pylori. American Journal of Tropical Medicine and Hygiene, 94(Issue 1). doi:10.4269/ajtmh.15-0297
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  Helicobacter pylori infection is among the most prevalent infections in the world and a key cause of gastric diseases; however, its route of transmission remains unclear. This study aimed to assess the potential for fecal-oral transmission of H. pylori by leveraging its association with a disease with known etiology. Utilizing serology data from the National Health and Nutrition Examination Survey (NHANES 1999; N = 6,347), the association between H. pylori and hepatitis A virus (HAV), a sensitive indicator for fecal-oral exposure, was assessed. Survey-weighted kappa and multiple logistic regression were used to quantify the association between H. pylori and HAV after controlling for age, sex, race, poverty, birthplace, crowding, smoking, and alcohol use. Concordant serological results were found among 69.8% of participants (survey-weighted ê = 0.30, 95% confidence interval [CI] = 0.26, 0.35). The adjusted odds of H. pylori seropositivity were over two times higher after adjusting for confounders (odds ratio = 2.27, 95% CI = 1.79, 2.87). Results from this study suggest H. pylori and HAV infections are strongly associated. Since HAV is primarily transmitted through the fecal-oral route, fecal-oral transmission may be an important pathway for H. pylori spread.
• Haenchen, S., Hayden, M., Dickinson, K., Walker, K. R., Jacobs, E. T., Brown, H. E., Gunn, J., Kohler, L., & Ernst, K. C. (2015). Mosquito avoidance practices and knowledge of arboviral diseases in cities with differing recent history of disease. American Journal of Tropical Medicine and Hygiene.
• Hansen, V., Oren, E., Dennis, L. K., & Brown, H. E. (2016). Infectious Disease Mortality Trends in the United States, 1980-2014. JAMA, 316(20), 2149-2151.
• Hansen, V., Oren, E., Dennis, L. K., & Brown, H. E. (2016). Infectious disease mortality trends in the United States, 1980-2014. JAMA - Journal of the American Medical Association, 316(Issue 20). doi:10.1001/jama.2016.12423
• Lega, J. C., & Brown, H. E. (2016). Data-driven outbreak forecasting with a simple nonlinear growth model. Epidemics, 17, 19-26. doi:http://dx.doi.org/10.1016/j.epidem.2016.10.002
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  Recent events have thrown the spotlight on infectious disease outbreak response. We developed a data-driven method, EpiGro, which can be applied to cumulative case reports to estimate the order of magnitude of the duration, peak and ultimate size of an ongoing outbreak. It is based on a surprisingly simple mathematical property of many epidemiological data sets, does not require knowledge or estimation of disease transmission parameters, is robust to noise and to small data sets, and runs quickly due to its mathematical simplicity. Using data from historic and ongoing epidemics, we present the model. We also provide modeling considerations that justify this approach and discuss its limitations. In the absence of other information or in conjunction with other models, EpiGro may be useful to public health responders.
• Lega, J., & Brown, H. E. (2016). Data-driven outbreak forecasting with a simple nonlinear growth model. Epidemics, 17(Issue). doi:10.1016/j.epidem.2016.10.002
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  Recent events have thrown the spotlight on infectious disease outbreak response. We developed a data-driven method, EpiGro, which can be applied to cumulative case reports to estimate the order of magnitude of the duration, peak and ultimate size of an ongoing outbreak. It is based on a surprisingly simple mathematical property of many epidemiological data sets, does not require knowledge or estimation of disease transmission parameters, is robust to noise and to small data sets, and runs quickly due to its mathematical simplicity. Using data from historic and ongoing epidemics, we present the model. We also provide modeling considerations that justify this approach and discuss its limitations. In the absence of other information or in conjunction with other models, EpiGro may be useful to public health responders.
• Shelly, E. M., Acuna-Soto, R., Ernst, K. C., Sterling, C. R., & Brown, H. E. (2016). A Critical Assessment of Officially Reported Chagas Disease Surveillance Data in Mexico.. Public Health Reports, 131.
• Shelly, E. M., Acuna-Soto, R., Ernst, K. C., Sterling, C. R., & Brown, H. E. (2016). A critical assessment of officially reported chagas disease surveillance data in Mexico. Public Health Reports, 131(Issue 1). doi:10.1177/003335491613100112
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  Objective. Chagas disease, a disease caused by Trypanosoma cruzi, disproportionately affects poor people throughout Latin America. In Mexico, assessments of officially reported burden have not been previously reported. To evaluate discontinuity between surveillance data and data from other sources, we used data from the Mexican Ministry of Health to describe the distribution of reported Chagas disease over time in Mexico and compare it with estimates from the literature. Methods. We summarized age and sex differences for Chagas cases and mortality for 1995–2013 and 1982–2010, respectively. We examined the spatial distribution of Chagas disease over time with respect to disease burden. We further compared officially reported figures with estimates from the literature. Results. Among 6,494 officially reported cases, rates of Chagas disease were highest in adults aged 25–44 years (47.3%). Mortality was highest in adults aged $45 years (423/495, 85.5%). The data indicated increasing temporal trends for incidence and mortality. The greatest burden occurred in southern states, with increasing spatial distribution over time. Fewer than 900 cases and 40 deaths were officially reported annually, in contrast to estimates from the literature of approximately 69,000 new cases and 25,000 deaths annually. Conclusion. While increasing trends in officially reported data have been observed, large discrepancies in case estimates compromise our understanding of Chagas disease epidemiology. Reported cases based on current practices are not enough to correctly assess the Chagas disease burden and spatial distribution in Mexico. Understanding the true epidemiology of this disease will lead to more focused and successful control and prevention strategies to decrease disease burden.
• Brown, H. E., Young, A., Lega, J., Andreadis, T. G., Schurich, J., & Comrie, A. (2015). Projection of Climate Change Influences on U.S. West Nile Virus Vectors. Earth Interactions, 19.
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  While estimates of the impact of climate change on health are necessary for health care planners and climate change policy makers, models to produce quantitative estimates remain scarce. We describe a freely available dynamic simulation model parameterized for three West Nile virus vectors, which provides an effective tool for studying vector-borne disease risk due to climate change. The Dynamic Mosquito Simulation Model is parameterized with species specific temperature-dependent development and mortality rates. Using downscaled daily weather data, we estimate mosquito population dynamics under current and projected future climate scenarios for multiple locations across the country. Trends in mosquito abundance were variable by location, however, an extension of the vector activity periods, and by extension disease risk, was almost uniformly observed. Importantly, mid-summer decreases in abundance may be off-set by shorter extrinsic incubation periods resulting in a greater proportion of infective mosquitoes. Quantitative descriptions of the effect of temperature on the virus and mosquito are critical to developing models of future disease risk.
• Clark, R., Taylor, A., Garcia, F., Krone, T., & Brown, H. E. (2015). Recognizing the Role of Skunks in Human and Animal Rabies Exposures in the Southwest. Vector borne and Zoonotic Diseases, 15(8), 494-501.
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  Rabies is arguably the most important viral zoonotic disease worldwide with an estimated 55,000 human deaths each year. Globally, dogs are the primary animals affected. In the United States, especially on the East Coast, raccoons and bats are the primary reservoir. However, in the southwestern United States, skunk and bat rabies play a large role. We describe the epidemiology and environmental risk factors associated with rabies in the US Southwest using exposure data for 2004-2012 from one Arizona county as a case study. Unlike other parts of the country, here bats and skunks are the most commonly collected positive animals (62% and 32%, respectively). Even though most of the positive animals were bats, human and domestic animal exposures were primarily a result of skunk interactions (58% and 50%, respectively). Consequently, the majority of exposures occur early in the year, January and February, when the majority of skunk pickups also occur. Using public health surveillance data, our study highlights the importance of recognizing the role of skunks in human and animal exposures in the southwestern United States. Consistent with a "One Health" approach, our data show how wildlife and domestic animal and human exposures are associated and informative to one another.
• Nsoesie, E. O., Ricketts, R. P., Brown, H. E., Fish, D., Durham, D. P., Ndeffo Mbah, M. L., Christian, T., Ahmed, S., Marcellin, C., Shelly, E., Owers, K., Wenzel, N., Galvani, A. P., & Brownstein, J. S. (2015). Spatial and temporal clustering of chikungunya virus transmission in Dominica. PLoS Neglected Tropical Diseases, 9(8), e0003977.
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  Using geo-referenced case data, we present spatial and spatio-temporal cluster analyses of the early spread of the 2013-2015 chikungunya virus (CHIKV) in Dominica, an island in the Caribbean. Spatial coordinates of the locations of the first 417 reported cases observed between December 15th, 2013 and March 11th, 2014, were captured using the Global Positioning System (GPS). We observed a preponderance of female cases, which has been reported for CHIKV outbreaks in other regions. We also noted statistically significant spatial and spatio-temporal clusters in highly populated areas and observed major clusters prior to implementation of intensive vector control programs suggesting early vector control measures, and education had an impact on the spread of the CHIKV epidemic in Dominica. A dynamical identification of clusters can lead to local assessment of risk and provide opportunities for targeted control efforts for nations experiencing CHIKV outbreaks.
• Nsoesie, E. O., Ricketts, R. P., Brown, H. E., Fish, D., Durham, D. P., Ndeffo Mbah, M. L., Christian, T., Ahmed, S., Marcellin, C., Shelly, E., Owers, K., Wenzel, N., Galvani, A. P., & Brownstein, J. S. (2015). Spatial and temporal clustering of chikungunya virus transmission in dominica. PLoS Neglected Tropical Diseases, 9(Issue 8). doi:10.1371/journal.pntd.0003977
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  Using geo-referenced case data, we present spatial and spatio-temporal cluster analyses of the early spread of the 2013–2015 chikungunya virus (CHIKV) in Dominica, an island in the Caribbean. Spatial coordinates of the locations of the first 417 reported cases observed between December 15th, 2013 and March 11th, 2014, were captured using the Global Positioning System (GPS). We observed a preponderance of female cases, which has been reported for CHIKV outbreaks in other regions. We also noted statistically significant spatial and spatio-temporal clusters in highly populated areas and observed major clusters prior to implementation of intensive vector control programs suggesting early vector control measures, and education had an impact on the spread of the CHIKV epidemic in Dominica. A dynamical identification of clusters can lead to local assessment of risk and provide opportunities for targeted control efforts for nations experiencing CHIKV outbreaks.
• Reyes-Castro, P. A., Harris, R. B., Brown, H. E., Christopherson, G. L., & Ernst, K. C. (2017). Spatio-temporal and neighborhood characteristics of two dengue outbreaks in two arid cities of Mexico. Acta Tropica, 167, 174-182.
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  Little is currently known about the spatial-temporal dynamics of dengue epidemics in arid areas. This study assesses dengue outbreaks that occurred in two arid cities of Mexico, Hermosillo and Navojoa, located in northern state of Sonora. Laboratory confirmed dengue cases from Hermosillo (N=2730) and Navojoa (N=493) were geocoded by residence and assigned neighborhood-level characteristics from the 2010 Mexican census. Kernel density and Space-time cluster analysis was performed to detect high density areas and space-time clusters of dengue. Ordinary Least Square regression was used to assess the changing socioeconomic characteristics of cases over the course of the outbreaks. Both cities exhibited contiguous patterns of space-time clustering. Initial areas of dissemination were characterized in both cities by high population density, high percentage of occupied houses, and lack of healthcare. Future research and control efforts in these regions should consider these space-time and socioeconomic patterns.
• Sedda, L., Morley, D., & Brown, H. E. (2015). Characteristics of Wind-Infective Farms of the 2006 Bluetongue Serotype 8 Epidemic in Northern Europe. EcoHealth, 12(3), 461-7.
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  Bluetongue is a Culicoides-borne viral disease of livestock. In 2006, northern Europe experienced a major outbreak of this disease with devastating effects on the livestock industry. The outbreak quickly spread over the region, primarily affecting cattle and sheep. A previous analysis of the role of vector flight and wind in the spread of this virus across northern Europe indicated that infection at 1,326 (65%) of the reported infected farms could be traced back to just 599 (29%) farms (wind-infective farms). Rather than focusing on presence or absence of vectors or difference between infected and non-infected farms, we investigate the zoological and environmental characteristics of these 599 wind-infective farms (which can be thought of as super-spreaders) in order to characterize what makes them distinct from non-infective farms. Differences in temperature, precipitation, and the density of sheep at individual farms were identified between these two groups. These environmental and zoological factors are known to affect vector abundance and may have promoted bluetongue virus transmission. Identifying such ecological differences can help in the description and quantification of relative risk in affected areas.
• Sedda, L., Morley, D., & Brown, H. E. (2015). Characteristics of Wind-Infective Farms of the 2006 Bluetongue Serotype 8 Epidemic in Northern Europe. EcoHealth, 12(Issue 3). doi:10.1007/s10393-014-1008-x
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  Bluetongue is a Culicoides-borne viral disease of livestock. In 2006, northern Europe experienced a major outbreak of this disease with devastating effects on the livestock industry. The outbreak quickly spread over the region, primarily affecting cattle and sheep. A previous analysis of the role of vector flight and wind in the spread of this virus across northern Europe indicated that infection at 1,326 (65%) of the reported infected farms could be traced back to just 599 (29%) farms (wind-infective farms). Rather than focusing on presence or absence of vectors or difference between infected and non-infected farms, we investigate the zoological and environmental characteristics of these 599 wind-infective farms (which can be thought of as super-spreaders) in order to characterize what makes them distinct from non-infective farms. Differences in temperature, precipitation, and the density of sheep at individual farms were identified between these two groups. These environmental and zoological factors are known to affect vector abundance and may have promoted bluetongue virus transmission. Identifying such ecological differences can help in the description and quantification of relative risk in affected areas.
• Harris, R. B., Scranton, R. A., Oren, E., Musuku, S., Murakami, T., Harris, R. B., Chen, Z., & Brown, H. E. (2014). A Survey of Screening and Treatment Practices for Helicobacter pylori in the United States: 144. The American Journal of Gastroenterology, 109, S45. doi:10.14309/00000434-201410002-00144
• Wang, D., Bowman, D. D., Brown, H. E., Harrington, L. C., Kaufman, P. E., McKay, T., Nelson, C. T., Sharp, J. L., & Lund, R. (2014). Factors influencing U.S. canine heartworm (Dirofilaria immitis) prevalence. Parasites & Vectors, 7, 264.
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  This paper examines the individual factors that influence prevalence rates of canine heartworm in the contiguous United States. A data set provided by the Companion Animal Parasite Council, which contains county-by-county results of over nine million heartworm tests conducted during 2011 and 2012, is analyzed for predictive structure. The goal is to identify the factors that are important in predicting high canine heartworm prevalence rates.
• Wang, D., Bowman, D. D., Brown, H. E., Harrington, L. C., Kaufman, P. E., McKay, T., Nelson, C. T., Sharp, J. L., & Lund, R. (2014). Factors influencing U.S. canine heartworm (Dirofilaria immitis) prevalence. Parasites and Vectors, 7(Issue 1). doi:10.1186/1756-3305-7-264
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  Background: This paper examines the individual factors that influence prevalence rates of canine heartworm in the contiguous United States. A data set provided by the Companion Animal Parasite Council, which contains county-by-county results of over nine million heartworm tests conducted during 2011 and 2012, is analyzed for predictive structure. The goal is to identify the factors that are important in predicting high canine heartworm prevalence rates. Methods. The factors considered in this study are those envisioned to impact whether a dog is likely to have heartworm. The factors include climate conditions (annual temperature, precipitation, and relative humidity), socio-economic conditions (population density, household income), local topography (surface water and forestation coverage, elevation), and vector presence (several mosquito species). A baseline heartworm prevalence map is constructed using estimated proportions of positive tests in each county of the United States. A smoothing algorithm is employed to remove localized small-scale variation and highlight large-scale structures of the prevalence rates. Logistic regression is used to identify significant factors for predicting heartworm prevalence. Results: All of the examined factors have power in predicting heartworm prevalence, including median household income, annual temperature, county elevation, and presence of the mosquitoes Aedes trivittatus, Aedes sierrensis and Culex quinquefasciatus. Interactions among factors also exist. Conclusions: The factors identified are significant in predicting heartworm prevalence. The factor list is likely incomplete due to data deficiencies. For example, coyotes and feral dogs are known reservoirs of heartworm infection. Unfortunately, no complete data of their populations were available. The regression model considered is currently being explored to forecast future values of heartworm prevalence. © 2014 Wang et al.; licensee BioMed Central Ltd.
• Borchert, J. N., Eisen, R. J., Holmes, J. L., Atiku, L. A., Mpanga, J. T., Brown, H. E., Graham, C. B., Babi, N., Montenieri, J. A., Enscore, R. E., & Gage, K. L. (2012). Evaluation and modification of off-host flea collection techniques used in northwest Uganda: Laboratory and field studies. Journal of Medical Entomology, 49(Issue 1). doi:10.1603/me11045
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  Quantifying the abundance of host-seeking fleas is critical for assessing risk of human exposure to flea-borne disease agents, including Yersinia pestis, the etiological agent of plague. Yet, reliable measures of the efficacy of existing host-seeking flea collection methods are lacking. In this study, we compare the efficacy of passive and active methods for the collection of host-seeking fleas in both the laboratory and human habitations in a plague-endemic region of northwest Uganda. In the laboratory, lighted "Kilonzo" flea traps modified with either blinking lights, the creation of shadows or the generation of carbon dioxide were less efficient at collecting Xenopsylla cheopis Rothchild and Ctenocephalides felis Bouch fleas than an active collection method using white cotton socks or cotton flannel. Passive collection using Kilonzo light traps in the laboratory collected significantly more X. cheopis than C. felis and active collection, using white socks and flannel, collected significantly more C. felis than X. cheopis. In field studies conducted in Uganda, Kilonzo traps using a flashlight were similar in their collection efficacy to Kilonzo traps using kerosene lamps. However, in contrast to laboratory studies, Kilonzo flea traps using flashlights collected a greater number of fleas than swabbing. Within human habitations in Uganda, Kilonzo traps were especially useful for collecting C. felis, the dominant species found in human habitations in this area. © 2012 Entomological Society of America.
• Borchert, J. N., Eisen, R. J., Holmes, J. L., Atiku, L. A., Mpanga, J. T., Brown, H. E., Graham, C. B., Babi, N., Montenieri, J. A., Enscore, R. E., & others, . (2012). Evaluation and modification of off-host flea collection techniques used in northwest Uganda: laboratory and field studies. Journal of Medical Entomology, 49, 210--214.
• Brown, H. E., Harrington, L. C., Kaufman, P. E., McKay, T., Bowman, D. D., Nelson, C. T., Wang, D., & Lund, R. (2012). Key factors influencing canine heartworm, Dirofilaria immitis, in the United States. Parasites & Vectors, 5.
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  An examination of the Companion Animal Parasite Council's (CAPC) canine heartworm data to clarify the spatial prevalence of heartworm in the United States. Factors thought to influence the spatial risk of disease, as identified in a recent CAPC workshop, are discussed.
• Craciunescu, V., Brown, H., Comrie, A., Zelicoff, A., Ward, T., Ragain, R., Simpson, G., Stanhope10, W., Kass-Hout11, T., Scharl12, A., & others, . (2012). Information and decision support systems. Environmental Tracking for Public Health Surveillance, 11, 369.
• Sedda, L., Brown, H. E., Purse, B. V., Burgin, L., Gloster, J., & Rogers, D. J. (2012). A new algorithm quantifies the roles of wind and midge flight activity in the bluetongue epizootic in northwest Europe. Proceedings of the Royal Society B: Biological Sciences, 279(Issue 1737). doi:10.1098/rspb.2011.2555
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  The 2006 bluetongue (BT) outbreak in northwestern Europe had devastating effects on cattle and sheep in that intensively farmed area. The role of wind in disease spread, through its effect on Culicoides dispersal, is still uncertain, and remains unquantified. We examine here the relationship between farm-level infection dates and wind speed and direction within the framework of a novel model involving both mechanistic and stochastic steps. We consider wind as both a carrier of host semio-chemicals, to which midges might respond by upwind flight, and as a transporter of the midges themselves, in a more or less downwind direction. For completeness, we also consider midge movement independent of wind and various combinations of upwind, downwind and random movements. Using stochastic simulation, we are able to explain infection onset at 94 per cent of the 2025 affected farms. We conclude that 54 per cent of outbreaks occurred through (presumably midge) movement of infections over distances of no more than 5 km, 92 per cent over distances of no more than 31 km and only 2 per cent over any greater distances. The modal value for all infections combined is less than 1 km. Our analysis suggests that previous claims for a higher frequency of long-distance infections are unfounded. We suggest that many apparent long-distance infections resulted from sequences of shorter-range infections; a ‘stepping stone’ effect. Our analysis also found that downwind movement (the only sort so far considered in explanations of BT epidemics) is responsible for only 39 per cent of all infections, and highlights the effective contribution to disease spread of upwind midge movement, which accounted for 38 per cent of all infections. The importance of midge flight speed is also investigated. Within the same model framework, lower midge active flight speed (of 0.13 rather than 0.5 m s21) reduced virtually to zero the role of upwind movement, mainly because modelled wind speeds in the area concerned were usually greater than such flight speed. Our analysis, therefore, highlights the need to improve our knowledge of midge flight speed in field situations, which is still very poorly understood. Finally, the model returned an intrinsic incubation period of 8 days, in accordance with the values reported in the literature. We argue that better understanding of the movement of infected insect vectors is an important ingredient in the management of future outbreaks of BT in Europe, and other devastating vector-borne diseases elsewhere.
• Sedda, L., Brown, H. E., Purse, B. V., Burgin, L., Gloster, J., & Rogers, D. J. (2012). A new algorithm quantifies the roles of wind and midge flight activity in the bluetongue epizootic in northwest Europe. Proceedings of the Royal Society of London B: Biological Sciences, rspb20112555.
• Brown, H. E., Doyle, M. S., Cox, J., Eisen, R. J., & Nasci, R. S. (2011). The effect of spatial and temporal subsetting on Culex tarsalis abundance models-a design for sensible reduction of vector surveillance. Journal of the American Mosquito Control Association, 27, 120--128.
• Brown, H. E., Doyle, M. S., Cox, J., Eisen, R. J., & Nasci, R. S. (2011). The effect of spatial and temporal subsetting on culex tarsalis abundance models-a design for sensible reduction of vector surveillance. Journal of the American Mosquito Control Association, 27(Issue 2). doi:10.2987/10-6077.1
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  Early identification of increasing mosquito activity is critical to effective mosquito control, particularly when increasing host-seeking behavior may be associated with increased risk of mosquito-borne disease. In this paper, we analyzed the temporal abundance pattern of the West Nile Virus vector, Culex tarsalis, in Fort Collins, CO, using an autoregressive integrated moving average model. We determined that an autoregressive model order 5 with lagged minimum temperatures was best at describing the seasonal abundance of Cx. tarsalis. We then tested the effect of using both temporal and spatial subsets of the data to determine the effect of reduced sampling effort on abundance predictions. We found that, if reduced trapping is necessary due to limited resources, removal of the least productive 1/3 or 1/4 of the traps produced the least erroneous predictions of seasonality represented in the observed data. We show that this productivity-based subset scheme performs better than other sampling effort reductions in generating the best estimate of Cx. tarsalis abundance per trap-night. © 2011 by the American Mosquito Control Association, Inc.
• Brown, H. E., Levy, C. E., Enscore, R. E., Schriefer, M. E., DeLiberto, T. J., Gage, K. L., & Eisen, R. J. (2011). Annual seroprevalence of Yersinia pestis in coyotes as predictors of interannual variation in reports of human plague cases in Arizona, United States. Vector-Borne and Zoonotic Diseases, 11, 1439--1446.
• Brown, H. E., Levy, C. E., Enscore, R. E., Schriefer, M. E., Deliberto, T. J., Gage, K. L., & Eisen, R. J. (2011). Annual seroprevalence of Yersinia pestis in coyotes as predictors of interannual variation in reports of human plague cases in Arizona, United States. Vector-Borne and Zoonotic Diseases, 11(Issue 11). doi:10.1089/vbz.2010.0196
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  Although several health departments collect coyote blood samples for plague surveillance, the association between reported human cases and coyote seroprevalence rates remains anecdotal. Using data from an endemic region of the United States, we sought to quantify this association. From 1974 to 1998, about 2,276 coyote blood samples from four Arizona counties were tested for serological evidence of exposure to Yersinia pestis, the causative agent of plague. Using a titer threshold presumed to be indicative of recent infection (serum titers of ≥1:256), we found a statistically significant relationship between years with >17% sero-positive coyotes and years with two or more human cases reported. Moreover, when the annual coyote seroprevalence rates were dichotomized at 17%, 84% of the years were correctly classified using four biologically relevant meteorological variables in a linear regression. This is the first time a statistically significant temporal association between human plague cases and coyote seroprevalence rates has been shown. However, issues with data resolution and surveillance effort that potentially limit the public health utility of using coyote seroprevalence rates are discussed. © Copyright 2011, Mary Ann Liebert, Inc.
• Brown, H. E., Yates, K. F., Dietrich, G., MacMillan, K., Graham, C. B., Reese, S. M., Helterbrand, W. S., Nicholson, W. L., Blount, K., Mead, P. S., & others, . (2011). An acarologic survey and Amblyomma americanum distribution map with implications for tularemia risk in Missouri. American Journal of Tropical Medicine and Hygiene, 84, 411--419.
• Brown, H. E., Yates, K. F., Dietrich, G., MacMillan, K., Graham, C. B., Reese, S. M., Helterbrand, W. S., Nicholson, W. L., Blount, K., Mead, P. S., Patrick, S. L., & Eisen, R. J. (2011). An acarologic survey and Amblyomma americanum distribution map with implications for tularemia risk in Missouri. American Journal of Tropical Medicine and Hygiene, 84(Issue 3). doi:10.4269/ajtmh.2011.10-0593
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  In the United States, tickborne diseases occur focally. Missouri represents a major focus of several tickborne diseases that includes spotted fever rickettsiosis, tularemia, and ehrlichiosis. Our study sought to determine the potential risk of human exposure to human-biting vector ticks in this area. We collected ticks in 79 sites in southern Missouri during June 7-10, 2009, which yielded 1,047 adult and 3,585 nymphal Amblyomma americanum, 5 adult Amblyomma maculatum, 19 adult Dermacentor variabilis, and 5 nymphal Ixodes brunneus. Logistic regression analysis showed that areas posing an elevated risk of exposure to A. americanum nymphs or adults were more likely to be classified as forested than grassland, and the probability of being classified as elevated risk increased with increasing relative humidity during the month of June (30-year average). Overall accuracy of each of the two models was greater than 70% and showed that 20% and 30% of the state were classified as elevated risk for human exposure to nymphs and adults, respectively. We also found a significant positive association between heightened acarologic risk and counties reporting tularemia cases. Our study provides an updated distribution map for A. americanum in Missouri and suggests a wide-spread risk of human exposure to A. americanum and their associated pathogens in this region. Copyright © 2011 by The American Society of Tropical Medicine and Hygiene.
• Cox, J., Brown, H. E., & Rico-Hesse, R. (2011). Variation in vector competence for dengue viruses does not depend on mosquito midgut binding affinity. PLoS Negl Trop Dis, 5, e1172.
• Cox, J., Brown, H. E., & Rico-Hesse, R. (2011). Variation in vector competence for dengue viruses does not depend on mosquito midgut binding affinity. PLoS Neglected Tropical Diseases, 5(Issue 5). doi:10.1371/journal.pntd.0001172
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  Background: Dengue virus genotypes of Southeast Asian origin have been associated with higher virulence and transmission compared to other genotypes of serotype 2 (DEN-2). We tested the hypothesis that genetic differences in dengue viruses may result in differential binding to the midgut of the primary vector, Aedes aegypti, resulting in increased transmission or vectorial capacity. Methodology/Principal Finding: Two strains of each of the four DEN-2 genotypes (Southeast Asian, American, Indian, and West African) were tested to determine their binding affinity for mosquito midguts from two distinct populations (Tapachula, Chiapas, Mexico and McAllen, Texas, USA). Our previous studies demonstrated that Southeast Asian viruses disseminated up to 65-fold more rapidly in Ae. aegypti from Texas and were therefore more likely to be transmitted to humans. Results shown here demonstrate that viruses from all four genotypes bind to midguts at the same rate, in a titer-dependent manner. In addition, we show population differences when comparing binding affinity for DEN-2 between the Tapachula and McAllen mosquito colonies. Conclusions: If midgut binding potential is the same for all DEN-2 viruses, then viral replication differences in these tissues and throughout the mosquito can thus probably explain the significant differences in dissemination and vector competence. These conclusions differ from the established paradigms to explain mosquito barriers to infection, dissemination, and transmission. © 2011 Cox et al.
• Brown, H. E., Ettestad, P., Reynolds, P. J., Brown, T. L., Hatton, E. S., Holmes, J. L., Glass, G. E., Gage, K. L., & Eisen, R. J. (2010). Climatic predictors of the intra- and inter-annual distributions of plague cases in New Mexico based on 29 years of animal-based surveillance data. American Journal of Tropical Medicine and Hygiene, 82(Issue 1). doi:10.4269/ajtmh.2010.09-0247
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  Within the United States, the majority of human plague cases are reported from New Mexico. We describe climatic factors involved in intra- and inter-annual plague dynamics using animal-based surveillance data from that state. Unlike the clear seasonal pattern observed at lower elevations, cases occur randomly throughout the year at higher elevations. Increasing elevation corresponded with delayed mean time in case presentation. Using local meteorological data (previous year mean annual precipitation, total degrees over 27°C 3 years before and maximum winter temperatures 4 years before) we built a time-series model predicting annual case load that explained 75% of the variance in pet cases between years. Moreover, we found a significant correlation with observed annual human cases and predicted pet cases. Because covariates were time-lagged by at least 1 year, intensity of case loads can be predicted in advance of a plague season. Understanding associations between environmental and meteorological factors can be useful for anticipating future disease trends. Copyright © 2010 by The American Society of Tropical Medicine and Hygiene.
• Brown, H. E., Ettestad, P., Reynolds, P. J., Brown, T. L., Hatton, E. S., Holmes, J. L., Glass, G. E., Gage, K. L., & Eisen, R. J. (2010). Climatic predictors of the intra-and inter-annual distributions of plague cases in New Mexico based on 29 years of animal-based surveillance data. American Journal of Tropical Medicine and Hygiene, 82, 95--102.
• Hartemink, N., Purse, B., Meiswinkel, R., Brown, H., De Koeijer, A., Elbers, A., Boender, G., Rogers, D., & Heesterbeek, J. (2009). Mapping the basic reproduction number (R 0) for vector-borne diseases: a case study on bluetongue virus. Epidemics, 1, 153--161.
• Brown, H. E., Childs, J. E., Diuk-Wasser, M. A., & Fish, D. (2008). Ecological factors associated with West Nile virus transmission, northeastern United States. Emerging Infectious Diseases, 14(Issue 10). doi:10.3201/eid1410.071396
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  Since 1999, West Nile virus (WNV) disease has affected the northeastern United States. To describe the spatial epidemiology and identify risk factors for disease incidence, we analyzed 8 years (1999-2006) of county-based human WNV disease surveillance data. Among the 56.6 million residents in 8 northeastern states sharing primary enzootic vectors, we found 977 cases. We controlled for population density and potential bias from surveillance and spatial proximity. Analyses demonstrated significant spatial spreading from 1999 through 2004 (p70%) forest cover. These results quantify urbanization as a risk factor for WNV disease incidence and are consistent with knowledge of vector species in this area.
• Brown, H. E., Childs, J. E., Diuk-Wasser, M. A., & Fish, D. (2008). Ecological factors associated with west nile virus transmission, northeastern United States. Emerging Infectious Diseases, 14(10), 1539-1545.
• Brown, H. E., Diuk-Wasser, M. A., Guan, Y., Caskey, S., & Fish, D. (2008). Comparison of three satellite sensors at three spatial scales to predict larval mosquito presence in Connecticut wetlands. Remote Sensing of Environment, 112(5), 2301-2308.
• Brown, H. E., Diuk-Wasser, M. A., Guan, Y., Caskey, S., & Fish, D. (2008). Comparison of three satellite sensors at three spatial scales to predict larval mosquito presence in Connecticut wetlands. Remote Sensing of Environment, 112(Issue 5). doi:10.1016/j.rse.2007.10.005
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  Satellite imagery can be used to identify suitable habitat for mosquitoes in areas inaccessible or lacking sufficient ground-based information about the environment but current applications are limited by the spatial and spectral resolution of the sensors. Here, models used to compare prediction of the presence of Anopheles punctipennis larvae in Connecticut wetlands were built using stepwise logistic regression and compared by Akaike's Information Criterion (AIC). Vegetation indices were extracted from three satellite sensor scenes (Hyperion, ASTER and Landsat-TM) at three scales (pixel, wetland perimeter, and wetland area). The best models were developed using ASTER (ROC = 0.80, p = 0.01, AIC 65.37) and Hyperion (ROC = 0.81, p < 0.01, AIC 66.40) at the wetland area level. The Disease Water Stress Index (DWSI), a measure of leaf water content, and Normalized Difference Vegetation Index (NDVI) were significant in many of the models. This comparison of satellite based models demonstrates higher spatial and spectral resolution of ASTER and Hyperion resulted in more parsimonious models than Landsat-TM models. The need for continued research and development into sensors with increased spatial and spectral resolution and the development of mosquito specific indices is discussed. © 2007 Elsevier Inc. All rights reserved.
• Brown, H. E., Paladini, M., Cook, R. A., Kline, D., Barnard, D., & Fish, D. (2008). Effectiveness of mosquito traps in measuring species abundance and composition. Journal of Medical Entomology, 45(3), 517-521.
• Brown, H. E., Paladini, M., Cook, R. A., Kline, D., Barnard, D., & Fish, D. (2008). Effectiveness of mosquito traps in measuring species abundance and composition. Journal of Medical Entomology, 45(Issue 3). doi:10.1603/0022-2585(2008)45[517:eomtim]2.0.co;2
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  Mosquito species abundance and composition estimates provided by trapping devices are commonly used to guide control efforts, but knowledge of trap biases is necessary for accurately interpreting results. We tested the hypothesis that commercially available traps (Mosquito Magnet-Pro, the Mosquito Magnet-X) would be significant improvements over the CDC Miniature Light Trap with respect to abundance, species diversity, and measures of recruitment in a wooded area of the Bronx Zoo in New York City, NY. The Mosquito Magnet-Pro collected significantly more mosquitoes (n = 1,117; mean per night, 124 ± 28.3) than the CDC Miniature Light Trap (n = 167; mean per night, 19 ± 5.5). The Simpson's diversity index was greatest for the Mosquito Magnet-Pro. A CDC light trap from a simultaneous surveillance project was located 15 m away and used as a control trap to test for significant differences in mosquito counts on nights with or without the experimental traps. There were no significant differences between nights, indicating the test traps did not recruit beyond 15 m. The traps differed significantly in abundance, but they had similarly limited sampling areas. Measured differences in abundance were independent of differences in diversity. This study highlights how differences between traps might affect species abundance and composition estimates. © 2008 Entomological Society of America.
• Brown, H., Duik-Wasser, M., Andreadis, T., & Fish, D. (2008). Remotely-sensed vegetation indices identify mosquito clusters of West Nile virus vectors in an urban landscape in the northeastern United States. Vector-borne and Zoonotic Diseases, 8(2), 197-206.
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  Heterogeneity in urban landscapes can influence the effectiveness of mosquito-borne disease control. We used remotely sensed vegetation indices to discriminate among mosquito habitats within a densely populated urban environment in New Haven, CT. ASTER derived vegetation indices were identified for 16 sites where adult mosquitoes were trapped over the summer of 2004. Canonical correlation analysis showed a significant relationship between the environmental variables (normalized difference vegetation index, disease/water stress index and distance to water) and four local West Nile virus competent vectors (Cx. pipiens, Cx. restuans, Cx. salinarius, and Ae. vexans) (0.93, P = 0.03) explaining 86% of the variance in the environmental and mosquito measures. Sites were clustered based on these remotely sensed environmental variables. Three clusters were identified which provide insight into the distribution of West Nile virus vectors in an urban area. Identification of habitat differences of mosquitoes within the urban landscape has important implications for understanding West Nile virus transmission and for control of vector-competent mosquito species.
• Purse, B. V., Brown, H. E., Harrup, L., Mertens, P. P., & Rogers, D. J. (2008). Invasion of bluetongue and other orbivirus infections into Europe: The role of biological and climatic processes. OIE Revue Scientifique et Technique, 27(Issue 2). doi:10.20506/rst.27.2.1801
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  The invasion of multiple strains of the midge-borne bluetongue virus into southern Europe since the late 1990s provides a rare example of a clear impact of climate change on a vector-borne disease. However, the subsequent dramatic continent-wide spread and burden of this disease has depended largely on altered biotic interactions with vector and host communities in newly invaded areas. Transmission by Palearctic vectors has facilitated the establishment of the disease in cooler and wetter areas of both northern and southern Europe. This paper discusses the important biological and climatic processes involved in these invasions, and the lessons that must be drawn for effective risk management of bluetongue and other midge-borne viruses in Europe.
• Purse, B. V., Brown, H. E., Harrup, L., Mertens, P., & Rogers, D. J. (2008). Invasion of bluetongue and other orbivirus infections into Europe: the role of biological and climatic processes. Revue Scientifique et Technique-Office International des Epizooties, 27(2), 427-442.
• Diuk-Wasser, M. A., Brown, H. E., Andreadis, T. G., & Fish, D. (2006). Modeling the spatial distribution of mosquito vectors for West Nile virus in Connecticut, USA. Vector-borne and Zoonotic Diseases, 6(3), 283-295.
• Eden, G. F., Joseph, J. E., Brown, H. E., Brown, C. P., & Zeffiro, T. A. (1999). Utilizing hemodynamic delay and dispersion to detect fMRI signal change without auditory interference: The behavior interleaved gradients technique. Magnetic Resonance in Medicine, 41(1), 13-20.
• Eden, G. F., Joseph, J. E., Brown, H. E., Brown, C. P., & Zeffiro, T. A. (1999). Utilizing hemodynamic delay and dispersion to detect fMRI signal change without auditory interference: The behavior interleaved gradients technique. Magnetic Resonance in Medicine, 41(Issue 1). doi:10.1002/(sici)1522-2594(199901)41:1<13::aid-mrm4>3.0.co;2-t
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  A major problem associated with the use of functional magnetic resonance imaging (fMRI) is the attendant gradient noise, which causes undesirable auditory system stimulation. A method is presented here that delays data acquisition to a period immediately after task completion, utilizing the physiological delay and dispersion between neuronal activity and its resulting hemodynamic lag. Subjects performed finger movements with the gradients off, followed by a rest period with the gradients on. This resulted in task-related signals comparable to those obtained with concurrent task performance and image data acquisition. This behavior interleaved gradients technique may be particularly useful for the studies involving auditory stimulation or overt verbal responses.
• Zeffiro, T. A., Joseph, J. E., Eden, G. F., Brown, H. E., & Brown, C. P. (1998). fMRI acquisition without auditory interference: The "flatcar" design. NeuroImage, 7(4), S538. doi:10.1016/s1053-8119(18)31371-5
• Helmbrecht, G. D., Farhat, M. Y., Lochbaum, L., Brown, H. E., Yadgarova, K. T., Eglinton, G. S., & Ramwell, P. W. (1996). L-Arginine reverses the adverse pregnancy changes induced by nitric oxide synthase inhibition in the rat. American Journal of Obstetrics and Gynecology, 175(4), 800-805.

Proceedings Publications

• Roach, M., Owen, G., Mcmahan, B., Keith, L., Brown, H. E., Berisha, V., & Austhof, E. (2020). Participation and Engagement of Public Health Stakeholders in Climate and Health Adaptation. In Atmosphere, 11, 265.
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  Stakeholder participation at the intersection of climate and health is essential to assess and plan for the human health impacts of current and projected climate-sensitive hazards. Using the Maricopa County Department of Public Health (MCDPH) Coalition on Climate Change and Public Health workgroup and the Climate Assessment for the Southwest (CLIMAS) program as examples, this paper describes the important role of scientist–public health stakeholder collaboratives in addressing the public health impacts of climate-sensitive hazards. Using the MCDPH and CLIMAS stakeholder groups, stakeholder connections were mapped to show relationships between the organization types and connections between scientists and public health stakeholders. Stakeholders, defined as meeting attendees, were primarily individuals from academic institutions (n = 175), government agencies (n = 114), non-profits (n = 90), and health departments (n = 85). Engaging public health stakeholders in transdisciplinary regional climate initiatives and addressing gaps in their networks helped these programs to develop more collaborative projects over time.

Presentations

• Brown, H. E., Keith, L., Roach, M., Owen, G., McMahan, B., Berisha, V., & Austhof, E. (2019, December 13). Engaging public health stakeholders in climate change adaptation: Lessons learned from Maricopa County, AZ and the Climate Assessment for the Southwest. Fall Meeting 2019. San Francisco, California: American Geophysical Union.
• Beamer, P., O'Rourke, M. K., Guerra, S., Brown, H. E., Lopez-Galvez, N., & Lothrop, N. (2018, August). Escape to America: Adapting European Study for Cohorts for Air Pollution Effects (ESCAPE) Methods to the Desert Southwestern US. Joint meeting of the International Society of Exposure Science and the International Society of Environmental Epidemiology.
• Beamer, P., O'Rourke, M. K., Guerra, S., Furlong, M., Brown, H. E., Bell, M. L., & Lothrop, N. (2017, Fall). Modeling Historic Air Pollution Concentrations with Land Use Regression in Tucson, AZ. International Society of Exposure Science Conference. Research Triangle Park, NC.
• Lega, J. C., & Brown, H. E. (2015, May). Modeling the Spread of Chikungunya in the Caribbean and Central America. DARPA Chikungunya Challenge Finale. DARPA: DARPA.
• Lega, J. C., & Brown, H. E. (2015, October). Modeling the Spread of Chikungunya in the Caribbean and Central America. UA Microlunch SeriesUniversity of Arizona.

Poster Presentations

• Murakami, T., Scranton, R., Brown, H. E., Harris, R. B., Zhao, C., Musuku, S., & Oren, E. (2014, October). A Survey of Screening and Treatment Practices for Helicobacter pylori in the United States. American College of Gastroenterology.. Philadelphia, PA.
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  Murakami T, Scranton R, Brown H, Harris RB, Chen Z, Musuku S, Oren E. A Survey of Screening and Treatment Practices for Helicobacter pylori in the United States. Poster presentation at the American College of Gastroenterology 79th Annual Scientific Meeting, Philadelphia, PA, October 2014.

Case Studies

• Tabor, J., Schweers, N., Rabby, Q., Lega, J. C., Hondula, D., Clark, R., Brown, H. E., & Roach, M. (2017. Projections of Climate Impacts on Vector-Borne Diseases and Valley Fever in Arizona(p. 20).

Others

• Brown, H. E., Keith, M., Currans, K. M., Chambers, S., Austhof, E. C., & McCesney, C. R. (2023, Nov.). Cooling Center Walkshed & Transit Accessibility Analysis. A Report by the Building Resilience Against Climate Effects (BRACE) Team at the University of Arizona in Cooperation with the Pima County Health Department..
• Austhof, E., Keith, L., Brown, H. E., & Chambers, S. (2022, September). Summary of Body Heat Exposure Layer Development.
• Van Ohlen, K., Brown, H. E., Keith, L., Austhof, E., Watkins, L., & Chambers, S. (2022, August). Summary of Pima County Cooling Center Spatial Optimization. University of Arizona.