Adenaiye, Oluwasanmi (UMD School of Public Health)
des Mesquita, Jacob (UMD School of Public Health)
Milton, Donald (UMD School of Public Health)
Background: There are critical questions and knowledge gaps concerning modes of transmission of acute respiratory infections (ARI) including influenza and the factors that influence transmission risk in communities and illness severity. Illness severity and transmission risk can be affected by host’s socio-behavioral and physical environment, host defense mechanisms and virulence of the infectious agents. Uncertainties remain, however, with respect to the relative importance and role of each of these factors. A thorough understanding of these requires highly enhanced epidemiological surveillance data from a comprehensive study design.
Objectives: 1. To identify cases with a high and low probability of transmission while controlling for variability in CO2 concentration. 2. To identify contacts with high susceptibility and describe their phenotype. 3. To evaluate how much of an influence the environmental conditions have on the above.
Approach: We recruited a cohort of UMD college dormitory students and closely monitored their social and physical environment, gene expression, and microbiome of ARI cases. For each of the identified cases, we recruited up to 4 contacts and closely monitored them to identify secondary transmission events while also monitoring their social, physical, gene expression and microbiome.
Results: Still being computed
Importance to public health: The study design offers a unique method of studying ARI transmission because unlike other transmission studies, it precisely mimics conditions encountered in real life transmission events.
Agha, Crystal (School of Public Health (UMD))
Wilson, Sacoby (UMD School of Public Health)
Background: Brandywine, Maryland, an unincorporated town in Prince George's County, has many locally unwanted land uses (LULUs) such as gas-fired power plants, a Superfund site, a fly ash landfill, a sludge lagoon, 10-12 surface mining operations, a sludge pond, and diesel emissions (3500 diesel truck trips/day). There is scheduled to be five power plants in a 13-mile radius of Brandywine, making this area one of the largest power plant clusters in the United States. The power plants and diesel trucks can emit air pollutants including particulate matter, volatile organic compounds (VOCs), black carbon, and other air toxics that can impact human health.
Goal: The aim of this study is to assess baseline levels of particulate matter (PM2.5) levels at recreational parks, schools, and commercial areas in close proximity to the Keys Energy Center power plant.
Objectives: Our objective is to determine baseline PM2.5 levels in Brandywine prior to the opening of the new facility. We hypothesize there will be higher levels of PM2.5 at locations closer to roadways from commuter and industrial traffic compared to locations farther away. We hypothesize there will be higher PM2.5 levels at local community centers and recreational locations after the power plant is open.
Approach: Air quality monitoring was conducted through the use of the Airbeam, a real-time personal air monitoring sensor that measures PM2.5 (µg/m3), temperature (℉), sound (dB), and humidity (%). Air quality levels were being recorded at 1-second intervals through the AirCasting app. These were conducted in July 2017 during off-peak hours in the morning. Researchers also considered meteorological conditions and traffic counts at sites near roadways.
Results: The PM levels at the five different sites ranged from 2 µg/m3 to 38 µg/m3. The range for the overall averages for the five different sites were from 3 µg/m3 to 5 µg/m3. The highest PM readings were observed at the section of the park closest to the new facility.
Importance to public health: Creating a baseline assessment of air quality near these environmental health hazards will allow us to track changes in air quality and assess exposure-disease associations for at-risk populations.
Background: The local food environment plays a critical role in determining individual and community health. Some communities, defined as food swamps, have an abundance of unhealthy food options, such as convenience stores and fast food restaurants, that are more readily available and accessible than healthy food outlets, such as supermarkets. Lack of access to affordable, healthy food can contribute to community stress and deprivation, and can lead to diet-related chronic diseases such as obesity and diabetes.
Goal: The goal of this project is to compare healthy food availability between three different communities within Prince George’s County, Maryland: Bladensburg, Greenbelt, and Hyattsville.
Objectives: As part of this project, we have the following objectives: 1) Compare and contrast the presence of supermarkets and grocery stores across our study neighborhoods; 2) Compare and contrast the quality of food stores in and across our study neighborhoods; 3) Assess in disparities in the types of food stores and quality of food stores in and across our study neighborhoods in regards to race/ethnicity and socioeconomic status (SES).
Approach: We visited all stores that sell food in Bladensburg, Greenbelt, and Hyattsville. We mapped each store and categorized by type: convenience, grocery store, supermarket, or other. We gave each store a food quality score based on the presence or absence of certain food items such as fresh produce and non-processed foods. In the next phase of the project, we plan to use US EPA’s EJSCREEN tool to assess differences in types of food stores and food quality scores in relation to race/ethnicity and SES at the census block group level.
Results: Based on preliminary results, we believe that: 1) Hyattsville will have more grocery stores and supermarkets than Bladensburg and Greenbelt per person and 2) Hyattsville will have higher rated stores compared to the other study neighborhoods.
Importance to public health: Our results will demonstrate a need for policymakers to address food injustice in Prince George’s County, Maryland. Limited availability and access to salutogenic food infrastructure such as supermarkets and grocery stores is a great challenge for many Americans, especially here in our own community.
Kaley, Beins (UMD SPH Maryland Institute of Applied Environmental Health)
Milton, Don (UMD SPH Maryland Institute of Applied Environmental Health)
Background: Vasculitis is an umbrella category covering a series of about 20 rare autoimmune disorders. Anti-neutrophil cytoplasmic antibody (ANCA)- associated vasculitis comprise three diagnostic forms of this autoimmune disorder: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome). Due to the severity of these disorders, the limited resources available to vasculitis researchers have mostly been targeted towards treatment and relapse prediction with a small amount of research examining genetic and environmental etiologic factors.
Goal: This research aims to develop novel methodology that can be used to examine potential environmental triggers of vasculitis in genetically pre-disposed individuals.
Objectives: In this project the authors: 1) review the existing literature on AAV etiology to identify gaps and promising areas for future research and 2) design a novel matched case-control study on gene-environment interaction in AAV pathogenesis.
Approach: Through collaborations with medical professionals, conversations with patients, and a review of AAV literature, the authors selected specific environmental exposures to be evaluated via a series of previously validated survey questions. These environmental exposures included potential triggers from occupational, travel, and leisure activities.
Results: This research is ongoing, and the authors plan to implement this validated methodology in a full study beginning in August 2018. Currently, two rheumatologists with access to AAV patients have shown interest in supporting the study and assisting with recruitment. Additionally, approximately 200 vasculitis patients have expressed interest in the study via Facebook support group message boards, demonstrating the significance of etiologic information to the vasculitis community.
Importance to public health: Given its chronic and potentially fatal nature, AAV has high social and economic costs; however, as a result of the unknown etiology of AAV, preventative care is often impossible. Studying the environmental etiology of AAV enables physicians to be proactive in identifying risk factors, which leads to increased monitoring and the potential for reducing AAV incidence.
Boyle, Meleah (UMD SPH MIAEH)
Garza, Mary (UMD SPH Behavioral and Community Health)
Beins, Kaley (UMD SPH MIAEH)
Dokshina, Dasha (UMD SPH MIAEH)
Merlo, Leyla (UMD SPH Public Health Science)
Feldman, Robert (UMD SPH Behavioral and Community Health)
Rous, Jennifer (UMD ESSR)
Quiros-Alcala, Lesliam (UMD SPH MIAEH)
Background: Latinos represent a growing demographic in the U.S., however, they are often overrepresented in lower-paying, higher risk jobs, placing them at an increased risk for work-related illnesses, including respiratory-related outcomes. Additional efforts are needed to identify environmental exposures of concern to inform future epidemiologic studies and interventions, as Latinos are an underrepresented population in environmental and occupational health research.
Goal: The goal of our project was to identify environmental and occupational exposures that may contribute to adverse health outcomes.
Objectives: We sought to examine the association between self-reported respiratory and allergic symptoms and exposure to 16 different products used at work and personal behaviors, including personal care product use.
Approach: Data was obtained from an ongoing study whose aim is to assess the health needs and to identify risk factors potentially linked to chronic diseases among Latino immigrant adults in Prince Georges County, MD. We administered a comprehensive questionnaire, which queried participants on demographic information, environmental exposures at the workplace and home environment, and we also collected biospecimens (i.e., urine, nasal swabs).
Results: Our population consisted of 156 adults most of which were female (87%) and Central American natives (81%). The mean age of participants was 51 years. Preliminary bivariate analyses indicate that using whiteboard cleaner is positively associated with reporting wheeze (p=0.02) and rashes (p=0.03) in the prior year; perfume use was moderately associated with wheeze in the prior year (p=0.06). Additional data and biospecimen analysis is underway.
Importance to public health: Study findings may inform intervention programs designed to reduce respiratory and allergic symptoms and improve overall health in Latino adults.
Bueno de Mesquita, Jacob (UMD SPH Maryland Institute for Applied Environmental Health)
Heidarinejad, Mohammad (Illinois Institute of Technology)
Addo, Kofi (UMD A. James Clark School of Engineering)
Dalgo, Daniel (UMD A. James Clark School of Engineering)
Mattise, Nicholas (UMD A. James Clark School of Engineering)
Srebric, Jelena (UMD A. James Clark School of Engineering)
Background: The purpose of this study is to estimate exposure to infectious, airborne influenza virus in a dormitory room given an infected roommate. To understand a typical quantity of infectious virus in the exhaled breath of campus cases, we take advantage of observed viral shedding from 142 influenza cases at the University of Maryland, described in Yan et al., 2018. We couple this data with newly collected, dormitory room CO2, a marker of exhaled breath exposure, to estimate the dose of inhaled virus following the Rudnick-Milton equation (2003).
Objectives: Given the challenges with effective vaccine match, strategies designed to reduce influenza virus exposure are paramount to protecting population health. Effective exposure reduction draws upon knowledge of transmission via direct contact, large droplet spray, and fine particle aerosols. Contact and large droplet transmission can be mitigated by reducing close contact with infected individuals, washing hands, and sterilizing surfaces, as recommended by CDC. Protecting against airborne exposure poses a greater challenge, however, a household transmission study estimated that about half of influenza is spread by airborne, fine particle aerosols (<5um in aerodynamic diameter), and infection initiated this way may lead to enhanced respiratory symptoms (Cowling et al., 2013). Given the potential for fine particle aerosols to carry infectious virus, and to mix suspended in air, we employed continuous CO2 monitoring of dormitory rooms to estimate the rebreathed air fraction as a proxy for exposure to airborne virus. Transmission risk is inferred given the assumption that a single virus is infectious and follows a Poisson distribution.
Approach: Influenza virus shed into fine particle aerosols was quantified, using a G-II bioaerosol sampler from community acquired influenza cases season (Yan et al., 2018). 30% of cases had culturable virus by focus assay and the geometric mean of positive cases was 37 with geometric standard deviation of 4.4. Per Rudnick and Milton, a rebreathed air fraction is calculated as the difference between indoor and outdoor CO2 concentrations (PPM) divided by the volume fraction of CO2 added to exhaled breath during breathing, assumed to be 0.038. Then average virus concentration in a room was calculated for a triple with 1 case and 2 susceptibles, for an exposure period and later the average number of viruses breathed by a susceptible person, using equation 1, µ ̅=ptN ̅ (1) where p is the pulmonary ventilation rate (l/hr) assumed to be 480, t is the exposure time, assumed to be 8 hours, and N ̅(per l) is the average virus concentration in the room for total exposure time t. There is a poisson distributed probability that a susceptible person remained uninfected, and thus the probability of infection.
Results: The findings show that the rebreathed air fraction for each of the two representative dorm rooms is dramatically different, and the building with improved ventilation (dorm 2) somewhat reduces transmission risk, given the low dose for influenza. From an epidemic prevention standpoint, the critical rebreathed air threshold is 0.0035, which is an order of magnitude smaller than what was observed in dormitory 2. The average CO2 level at night (8am-8pm) for dormitories 1 and 2 were 1.57E+04 and 1.70E+03, respectively. Rebreathed air fractions, based on these CO2 levels were 0.40 and 0.033. Geometric mean for number of inhaled infectious viruses over an eight hour period were 79 and 7 respectively. Assuming infection can be caused by a single infectious particle, as suggested by Alford et al. (1966), the risk of airborne transmission for the 2 susceptibles in both dorms would be 100%. If the number of viruses inhaled by susceptibles were at 1 standard deviations below the geometric means, then that would result in infection risk of 100% and 50% for dormitories 1 and 2, respectively. If the number of viruses inhaled by susceptibles were at 1 standard deviations below the geometric means, then that would result in infection risk of 88% and 16% for dormitories 1 and 2, respectively. These infection risk outcomes warrant validation through additional analyses to account for various exposure conditions and infectious dose estimations.
Importance to public health: Results from this analysis show that there is significant risk of airborne transmission between roommates, given a single shedder. Overall this work suggests that there is room to further reduce aerosolized virus exposure through improved ventilation and/or filtration, and/or inactivation methods such as upper-room germicidal UV.
Cairns, Christopher (UMD SPH Epidemiology and Biostatistics)
Carter-Pokras, Olivia (UMD SPH Epidemiology and Biostatistics)
Payne-Sturges, Devon (UMD SPH Epidemiology and Biostatistics)
He, Xin (UMD SPH Epidemiology and Biostatistics)
Background: Arthritis and rheumatoid arthritis are highly prevalent among U.S. adults, but, the cause of the disease remains unknown. Identified risk factors for developing arthritis include age, sex, genetics, smoking, history of live births, obesity, and environmental factors. Exposure to mercury and other heavy metals has been associated with autoimmune diseases, but the association between mercury and arthritis is underexplored.
Goal: Using data from the 2013-2014 National Health and Nutrition Examination Survey (NHANES), this project will determine if adults with arthritis have higher levels of blood methyl mercury compared to healthy adults.
Objectives: • Determine the odds that an adult with arthritis will have higher levels of blood methyl mercury compared to adults without arthritis. • Determine the odds that an adult with rheumatoid arthritis will have higher levels of blood methyl mercury compared to adults without rheumatoid arthritis. • Establish whether gender, age, race, or BMI are confounding variables.
Approach: A secondary data analysis of the NHANES 2013-2014 was performed for adult participants who were at least 20 years of age, and had arthritis and blood methyl mercury data (n=2695). Weighted multiple logistic regression models were used to explore the association between arthritis/rheumatoid arthritis and blood methyl mercury levels while considering potential confounders.
Results: The weighted geometric mean blood methyl mercury levels for healthy adults, all adults with arthritis, and adults with rheumatoid arthritis are 0.91, 0.86, and 0.76 ug/l, respectively. After adjusting for age and obesity, the odds of adults reporting arthritis increased by 44% for every unit increase in log methyl mercury (95% CI = 1.13-1.84). The odds of adults reporting rheumatoid arthritis increased by 126% for every unit increase in log methyl mercury (95% CI = 1.29-3.95) after adjusting for age.
Importance to public health: Based on this cross-sectional analysis, exposure to methyl mercury was found to be positively associated with arthritis and rheumatoid arthritis. Future studies should consider a different study design to establish temporality.
Chopyk, Jessica (UMD SPH Maryland Institute for Applied Environmental Health)
Allard, Sarah (UMD SPH Maryland Institute for Applied Environmental Health)
Nasko, Daniel (UMD Center for Bioinformatics and Computational Biology)
Bui, Anthony (UMD SPH Maryland Institute for Applied Environmental Health)
Mongodin, Emmanuel (Institute for Genome Sciences and Department of Microbiology and Immunology)
Sapkota, Amy (UMD SPH Maryland Institute for Applied Environmental Health)
Background: Agricultural ponds have a great potential as a means of capture and storage of water for irrigation. However, pond topography (small size, shallow depth) leaves them susceptible to environmental, agricultural, and anthropogenic exposures that may influence microbial dynamics.
Goal: The aim of this project was to characterize the bacterial and viral communities of pond water in the Mid-Atlantic United States with a focus on the late season (October-December), where decreasing temperature and nutrient levels can affect the composition of microbial communities.
Objectives: (i) survey the bacterial consortium utilizing different filter pore sizes (1 μm and 0.2 μm); (ii) characterize the diversity and abundance of the bacteriophage within the viral community; and (iii) compare the phylogeny of pond viromes across time using the phylogenetically relevant, and biologically meaningful, Pol I protein.
Approach: Ten liters of freshwater from an agricultural pond were sampled monthly, and filtered sequentially through 1 μm and 0.2 μm filter membranes. Total DNA was then extracted from each filter, and the bacterial communities were characterized using 16S rRNA gene sequencing. The remaining filtrate was chemically concentrated for viruses, DNA-extracted, and shotgun sequenced.
Results: Bacterial community profiling showed significant shifts over time, corresponding to changes in the condition of the pond freshwater (e.g. pH, nutrient load). In addition, there were significant differences in the alpha-diversity and core bacterial operational taxonomic units (OTUs) between water fractions filtered through different pore sizes. The viral fraction was dominated by tailed bacteriophage of the order Caudovirales, largely those of the Siphoviridae family. Moreover, while present, genes involved in virulence/antimicrobial resistance were not enriched within the viral fraction during the study period. Instead, the viral functional profile was dominated by phage associated proteins, as well as those related to nucleotide production.
Importance to public health: Overall, these data suggest that farm pond water harbors a diverse core of interacting microbial species whose abundance is influenced by environmental variables and, therefore, may require water treatment technologies to assure its safety for use in irrigation.
Kelbick, Hillary (UMD - MIAEH)
Sapkota, Amy (UMD - MIAEH)
Lipchin, Clive (Arava Institute for Environmental Studies)
Background: The reuse of wastewater for agricultural irrigation is emerging in water scarce regions around the world, including the West Bank, Palestinian Authority. However, to our knowledge, no long-term testing of this water has been undertaken.
Goal: The purpose of this study is to 1) investigate the safety of agricultural irrigation water produced by small-scale, off-grid greywater treatment systems and 2) investigate the efficacy of these systems in reducing contaminants.
Objectives: 1) To investigate and compare the bacterial counts of two types of fecal bacteria, Escherichia coli and total Coliforms, in the influent and effluent over time; and 2) To investigate and compare basic chemical water quality parameters in the influent and effluent over time.
Approach: Water samples (n= 88) will be collected over eight months from three off-grid greywater systems. Bacterial levels will be tested using membrane filtration. Hach probes will be used to test pH and Electrical Conductivity. Turbidity will be tested for with a Lutron meter.
Results: Two out of three systems were within quality standards for pH and salinity. Turbidity values were highly variable over time and among the systems. Regarding bacterial levels, however, the data suggests that these systems are not effective at reducing bacterial levels to acceptable levels. 100% of samples violated quality standards for bacteria.
Importance to public health: Access to safe, abundant irrigation water sources is critical to public health. Safe irrigation water reduces the potential for diarrheal disease and foodborne disease outbreaks, while abundant irrigation water improves nutrition through increased access to fruits and vegetables.
Bara, Samuel (UMD SPH)
Woldu, Root (UMD SPH)
Wilson, Sacoby (UMD SPH Community Engagement)
Driver, Aubree (UMD SPH Maryland Institute for Applied Environmental Health)
Background: A wealth of research has shown that communities of color and low-income populations have been disproportionately burdened by environmental hazards and locally unwanted land uses (LULUs) including incinerators, power plants, landfills, and other pollution-intensive facilities. Unfortunately, the state of Maryland has made little progress in constructing tools to assess and address environmental injustice and related health issues. The National Center for Smart Growth has begun developing a new mapping tool for the state of Maryland known as Maryland EJSCREEN that highlights the prevalence and frequency of environmental hazards and LULUs and health risks for nearby populations.
Goal: The long-term goal is to use this tool to highlight areas with environmental justice issues, areas that need additional investments, and be used in permitted, regulations, zoning, and development decisions.
Objectives: The objectives of this project: 1) Collect information on environmental, social, economic, exposure, and health indicators that should be included in the Maryland EJSCREEN tool; 2) Obtain feedback on from various stakeholder groups on indicators that should be included in the tool and prioritized; and 3) demonstrate the utility of the EJSCREEN tool.
Approach: In collaboration with the Partnership in Active Learning in Sustainability (PALS), we performed a literature review of economic, social, environmental, exposure, and health indicators identified as important by several Prince George’s County community members and stakeholders through a series of demonstration workshops. Stakeholders included residents from the Port Towns, Environmental Action Council members, the Environmental Justice legislative team, and the Commission on Environmental Justice and Sustainable Communities. Flashcards, posters, and surveys were distributed to community members and stakeholders in order to gather valued feedback regarding which indicators were deemed necessary and acceptable to be highlighted in the Maryland EJSCREEN tool.
Results: We found that the demonstration workshops were quite effective in soliciting feedback from residents, advocates, health practitioners, policymakers, and other stakeholder groups.
Importance to public health: The tool can be used by local residents to advocate for new policies, better enforcement, and public health improvements. The tool can be used by government officials to build healthier, greener, more equitable, and more sustainable communities.
Ezeugoh, Rosemary (UMD SPH Maryland Institute of Environmental Health)
Wilson, Sacoby (UMD SPH Maryland Institute of Environmental Health)
Background: Ambient air pollution from stationary sources, industrial traffic, and commuter traffic can negatively impact air quality and human health including emissions of particulate matter and volatile organic compounds (VOCs). Ernest Maier, a concrete block plant located in Bladensburg, Maryland wants to expand to include a concrete batching plant on the same property. This expansion could further degrade air quality and impact the health of vulnerable residents.
Goal: The purpose of this study is to provide information on particulate matter (PM) and volatile organic compounds (VOCs) levels near residential areas in close proximity to commuter traffic and industrial activity associated with the concrete plant.
Objectives: 1. To determine human exposure to PM and VOCs in Bladensburg, Maryland. Hypothesis 1: Areas close to the concrete block plant will have higher exposure levels of PM and VOCs than areas farther away from the plant. 2. To assess variation in human exposure to PM and VOCs at different locations during different times of the day in Bladensburg, Maryland. Hypothesis 2: Individuals walking on highly trafficked roads will have higher exposure levels of PM and VOCs during on-peak periods than individuals walking on low trafficked roads during on-peak hours.
Approach: Air quality monitoring will be conducted in the community at six personal sites using the Airbeam, a real-time sensor that can measure PM2.5. The Atmotube is a real-time sensor that can be worn to measure VOCs via Air Quality Score Android app. Also, traffic counts will be conducted at the six personal monitoring locations. PurpleAir sensors will be installed at the fixed monitoring locations to measure PM10, PM2.5, and PM1 in real-time at locations near the concrete facility and local roadways.
Results: Based on preliminary results, we will see: 1) higher PM levels and possibly VOC levels at the fixed monitoring site closest to the concrete factory and 2) higher PM and VOC levels at locations closer to roadways and during rush hour traffic.
Importance to public health: This study will provide valuable information on human exposure to PM and VOCs that may be contributing to poor health outcomes in the community such as asthma.
Pan, He (Department of Geographical Science)
Feng, Kuishuang (Department of Geographical Science)
Baiocchi, Giovanni (Department of Geographical Science)
Hubacek, Klaus (Department of Geographical Science)
Background: Dietary patterns rich in animal foods, fat, and added sugar in the developed countries such as the United States are not only contributing significantly to multiple environmental issues, but also imposing a considerable burden of diseases by causing obesity, diabetes, heart diseases, stroke, etc. As a growing body of literature investigates whether there is an opportunity to improve the nutritional quality and reduce the environmental impacts of food are associated through the dietary patterns simultaneously, the heterogeneity of such food-health-environment nexus due to income inequality is however under-explored.
Goal: In this research, we examine whether the poor have dietary environmental impacts and the nutritional quality that are quite different from those of the rich, and provide policy implications in addressing the food-health-environment nexus with a consideration of equality.
Objectives: We estimate the greenhouse gas (GHG) emissions, water consumption, land appropriation, and energy consumption of the dietary patterns of various income groups using individual-level National Health and Nutrition Examination Survey; meanwhile, we assess the nutritional quality of these dietary patterns.
Approach: The environmental impacts are evaluated using an environmentally extended input-output analysis; the nutritional quality is evaluated using a score of Healthy Eating Index developed by United States Department of Agriculture.
Results: The results show that higher income is correlated with healthier, more nutrient-dense diets but also larger environmental impacts. With limited spendings on foods, individuals from low-income groups tend to purchase empty calories that are of both lower price and smaller environmental impacts.
Importance to public health: Our results call for a focus on social justice in eradicating malnutrition and improving the sustainability of the food system. We further provide implications for policymakers to consider the income inequality when addressing the food-health-environment nexus in the United States as well as other countries with similar socio-economic context.
Khan, Razeen (UMD School fo Public Health)
Lynch, Jason (UMD Biological Sciences)
Bueno de Mesquita, Jacob (UMD School of Public Health MIEH)
Milton, Donald (UMD School of Public Health MIEH)
Koutsoukos, Stefanos (UMD Chemistry and Biochemistry)
German, Jennifer (UMD School of Public Health MIEH)
Background: A college campus presents a unique environment to study transmission of respiratory illness as well the clinical progression of certain infections. The group sought out to determine if there was a differentiation in symptom presentation between bacterial and viral infection in addition to looking at the impact of certain lifestyle conditions on illness severity.
Goal: The goal of this research project is to determine significance differences between populations of students infected with both viral and bacterial targets.
Objectives: Based on the similarity of immunological responce similar symptom scores are expected. Also, negative confounding lifestyle factors are predicted to increase the risk of symptom onset by infection.
Approach: Clinical samples were collected from individuals with suspected acute respiratory infections from a cohort of living and learning program undergraduates during the Spring 2017 semester.
Results: Significant differences in the symptom presentation were found between viral and bacterial infection.
Importance to public health: A stronger association of symptom presentation with the normalization of confounding factors could eventually lead to a probabilistic correlation model of which could be used to better diagnose and treat infectious disease in the future.
Li, Andrew (UMD SPH)
Li, Alice (UMD SPH)
Shukla, Malavika (UMD SPH)
Cunningham, Laura (UMD SPH)
Background: Contrary to popular belief, researchers at the University of Maryland have found strong evidence that flu can be transmitted through breathing, and not just through coughing and sneezing. Breathing infectious aerosol particles which can stay suspended in air and transmit disease raises a concern regarding building ventilation. CO2 concentrations are used to estimate the ventilation rate in a room; high CO2 concentrations indicate poor ventilation.
Goal: We studied how factors such as ventilation, humidity, and temperature affected the CO2 concentration to analyze if buildings should change ventilation to decrease the prevalence of potential infectious aerosol particles.
Objectives: We examined data from six CO2 monitors collected over 17 days - five in poorly ventilated rooms in the School of Public Health and one mounted outside. Our objective was to compare the differences in humidity, temperature and ventilation in order to come up with a recommendation if buildings should be renovated so ideal factors are reached. We hypothesized that: Poor ventilation will cause high CO2 concentration Higher humidity will cause high CO2 concentration Higher temperature will cause high CO2 concentration
Approach: In order to study the effect of the aforementioned building factors, relevant data was collected using HOBO sensors. These sensors were mounted in rooms 301, 302, 303, 305, and 307 to measure each room’s average temperature, relative humidity, dew point, and carbon dioxide concentration, with data points taken every five minutes. In addition, a sensor was mounted outside of the School of Public Health to serve as a baseline comparison for outdoor air quality. At the end of the 17 day collection period, the data for each room was subsequently downloaded in a list format using the HOBO mobile app and converted to Excel files. Upon acquiring the data, we analyzed and compared the relationship between time and each of the ventilation variables for each room.
Importance to public health: Old buildings generally have poor ventilation, which can negatively affect the health of its residents and visitors. As the University of Maryland research shows, breathing can expel infectious aerosols that can remain suspended in the air. We believe that having even one sick person in a room with poor ventilation can greatly impact the chances of others in the room getting sick. Therefore, our study is designed to come up with an initial conclusion and recommendation for potential changes in ventilation in old buildings.
Wilson, Sacoby (UMD SPH Applied Environmental Health)
Gugssa, Wengiel (UMD SPH Public Health Science)
Mullen, Haley (UMD Environmental Science & Policy)
Background: Research as shown that low-income groups, communities of color, and marginalized populations have been differentially burdened by environmental hazards and locally unwanted land uses (LULUs) across the country. In Prince George’s County, there are a number of vulnerable populations impacted by health disparities that may be related to: 1) differential permitting of LULUs and 2) inequities in planning, zoning, and community development. To address these concerns, the County needs to develop and implement an environmental justice (EJ) plan.
Goal: The goal of this presentation is to discuss elements of the Prince George’s County Environmental Justice 2025 (EJ2025) plan, a blueprint for the County to advance environmental justice, improve public health, and achieve health equity.
Objectives: EJ2025 plan includes an assessment of EJ issues in Prince George’s County. The plan aims to mitigate the differential burden of environmental hazards and health risks on certain populations in the County. EJ2025 offers multiple strategies detailing how to incorporate environmental justice into the local development and policies in Prince George’s County.
Approach: The Prince George’s County Environmental Justice 2025 Plan began as a student project in MIEH730 and has expanded to include other UMD students. The plan includes goals, strategies, recommendations, and metrics related to five themes: lead, water quality, air quality, food security, and equitable development/zoning.
Results: The plan recommends that the County should incorporate: 1) the use of the Maryland EJSCREEN tool to assess areas that may have environmental justice risks, 2) meaningful involvement of impacted stakeholders in local environmental decision-making by establishing a county-wide Commission on Environmental Justice, 3) a moratorium on all permitting, zoning, and development activities in the County until all agencies are in compliance with Title VI of the Civil Rights Act; and 4) decisions that are evidence-based using sound, scientific practices.
Importance to public health: The plan if fully implemented can lead to improvements in health, community sustainability, and quality of life for overburdened and underserved residents in Prince George’s County.
Wilson, Sacoby (UMD SPH Maryland Institute for Applied Environmental Health)
Sapkota, Amy (UMD SPH Maryland Institute for Applied Environmental Health)
Background: Campylobacter is a leading cause of foodborne illness in the United States. Campylobacter infections have been associated with risk factors, such as the consumption of poultry and raw milk. Recent studies, including one in Maryland, have indicated that beyond food-related risk factors there are socioeconomic, agricultural and environmental risk factors for campylobacteriosis, including living in close contact with livestock and consumption of contaminated water. However, no previous studies have evaluated the association between consumption of water from a private well and campylobacteriosis rates in Maryland. Given that the Safe Drinking Water Act does not regulate the water quality of private wells, these could be an important non-foodborne transmission pathway for Campylobacter.
Goal: To evaluate the impact of consumption of water from a private well on the risk of campylobacteriosis in Maryland.
Objectives: The objective is to determine whether consumption of water from a private well is associated with the risk of campylobacteriosis in Maryland.
Approach: Campylobacteriosis case data was obtained from the Maryland FoodNet, which conducts active surveillance on confirmed cases of Campylobacter as well as 9 other pathogens. Only culture-confirmed cases of Campylobacter infection occurring in Maryland between 2007 and 2016 were considered. The Maryland homeowner well permits registry was obtained from the Maryland Department of the Environment. Data from all sources were linked by zip code and campylobacteriosis rates were calculated by zip code. A multivariate, zero-inflated Poisson regression model will be performed to determine the zip code-level association between the number of households in Maryland that rely on drinking water from private wells and the incidence of campylobacteriosis.
Results: A positive association is expected between consumption of water from private wells and the incidence of campylobacteriosis.
Importance to public health: This project will significantly increase our understanding of private wells as a risk factor for campylobacteriosis in Maryland. Results of this study can also be used to inform policies around private well regulations and to educate homeowners on proper well maintenance.
Ngo, Kelly (UMD)
Ajayi, Lola (UMD)
Lau, Gilbert (UMD)
Background: Respiratory illness is a common occurrence in campuses where large student body populations are at risk of developing certain types, especially in close quarters such as dormitorities. This projected was conducted in order to study the transmission rates of these pathogens.
Goal: The overall goal of the project is to make communities healthier by finding out what contributes to someone getting sick, identifying possible modes of transmission, and preparing preventive interventions.
Objectives: Specifically, the study looks at the spread of respiratory illness in specific dorms on the campus of the University of Maryland, College Park.
Approach: A cohort group of students living in specific dorms is assembled and asked to give samples when they are healthy, sick, and if they are listed as a contact of a sick person, samples as well then. The samples will then be collected based on the type of visit in which they are classified into. PCR techniques are used to analyze the samples and identify the identity of the virus.
Results: Among the data analyzed, influenza and coronavirus are the most prevalence in the dormitories on campus.
Importance to public health: The C.A.T.C.H. (Characterizing and Tracking College Health) Study is a respiratory illness study that seeks to understand what makes an infected person contagious.
Patterson, Rebecca (UMD SPH Maryland Institute for Applied Environmental Health)
Solaiman, Sultana (UMD AGNR Plant Science and Landscape Architecture)
Payne-Sturges, Devon (UMD SPH Maryland Institute for Applied Environmental Health)
Micallef, Shirley (UMD AGNR Plant Science and Landscape Architecture)
Background: The increasing demand for agricultural water requires identification and safety assessment of alternative water sources, as pathogenic bacteria in the water could cause health risks if transferred to growing produce. Some species of Enterococcus, an opportunistic pathogen and water quality indicator, exhibit antimicrobial resistance and can transfer resistance traits to other bacterial taxa, including human pathogens. Thus, it is important to consider antimicrobial resistance when assessing the safety of irrigation water for food crops.
Goal: The goal of this project is to evaluate the distribution and antimicrobial resistance of Enterococcus faecalis and E. faecium in surface and recycled wastewaters in the Mid-Atlantic region of the U.S.
Objectives: 1) Identify E. faecalis and E. faecium in enterococci isolate collection, recovered from surface and recycled wastewater samples from a variety of sites in the Mid-Atlantic. 2) Evaluate susceptibilities of E. faecalis and E. faecium isolates to a suite of antimicrobials. 3) Assess whether antimicrobial resistance in E. faecalis and E. faecium is associated with season, water type, temperature, pH and salinity.
Approach: Enterococcus species isolated from surface and recycled water samples collected between October 2016 and September 2017 have been archived in -80°C storage. To identify E. faecalis and E. faecium in the collection, PCR amplification targeting the species-specific ddl (D-Ala:D-Ala ligase) gene of two Enterococcus species, E. faecalis and E. faecium is being conducted on these isolates. Once the E. faecalis and E. faecium isolates are identified, antimicrobial susceptibility testing will be conducted to evaluate their susceptibility to a suite of antimicrobials, including ampicillin, ceftriaxone, ciprofloxacin, clindamycin, daptomycin, erythromycin, gatifloxacin, gentamicin, levofloxacin, linezolid, oxacillin + 2% NaCl, penicillin, quinupristin/dalfopristin, rifampicin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole, and vancomycin, using the microbroth dilution method.
Results: A total of 447 enterococci isolates from four water sources (reclaimed wastewater, non-tidal river, tidal river, pond) will be identified by species (E. faecalis, E. faecium, or other). Logistic regression will be used to evaluate correlation of antimicrobial resistance with season, water type, temperature, pH, and salinity.
Importance to public health: Understanding antimicrobial resistance in irrigation water and reducing risk to public health is critical in light of the shrinking treatment options for infectious diseases caused by antimicrobial resistant pathogens.
Remigio, Richard (UMD SPH Maryland Institute for Applied Environmental Health)
Topping, Alice (Renal Research Institute)
Rainmann, Jochen (Renal Research Institute)
Kotanko, Peter (Icahn School of Medicine)
Maddux, Frank (Renal Research Institute)
Sapkota, Amir (UMD SPH Maryland Institute for Applied Environmental Health)
Kinney, Patrick (BU SPH)
Background: Many studies on extreme heat and health have shown associations with morbidity and mortality within the general population around the world. There has been less focused work on heat vulnerability among individuals living with chronic diseases, particularly for end-stage renal disease treated with hemodialysis (HD).
Goal: We aimed to evaluate the associations between heat wave events and clinical parameters in urban HD populations in three northeastern cities.
Objectives: Hypothesis 1: Extreme heat events will be associated with physiological changes using clinical measures such as weight gain and blood pressure among HD patients. Hypothesis 2: Extreme heat events will be associated with increased mortality and hospitalization risks among hemodialysis patients.
Approach: We obtained data on physical and clinical measures collected during HD visits (EHR) between 2001 to 2012 in three cities: Boston, MA; New York City, NY, and Philadelphia, PA. We extracted meteorological data through the Local Climatological Database (LCD) from National Oceanic and Atmospheric Agency (NOAA) and generated extreme heat event exposure metrics based on single day upper percentile (95th, 97.5th, 99th) exceedances of air temperature and heat index for each location. We analyzed heat effects on inter-dialytic weight gain (IDWG), predialysis systolic and diastolic blood pressure (pre-SBP, pre-DBP), and mortality and hospitalization. Repeated measures regression models controlled for temporal-based confounders: seasonality, long-term trends, and day of the week.
Results: IDWG, pre-SBP, and pre-DBP exhibited highly significant (p<0.005) mean decreases in association with same-day and one-day lag heat events in all three cities. We observed increased mortality among patients residing in Boston during specific extreme heat events suggesting location-specific variation in responses. Hospitalization risks were not evident during extreme heat events. Clinical measures responded to outdoor temperature suggesting more proximate physiological stress.
Importance to public health: These results suggest that patients with ESRD may be especially vulnerable to extreme heat, exposures to which are likely to increase with climate change. Preliminary work has implications for developing location-specific heat adaptation strategy plans for ESRD patients.
Remigio, Richard (UMD SPH Maryland Institute for Applied Environmental Health)
Rainmann, Jochen (Renal Research Institute)
Maddux, Frank (Renal Research Institute)
Sapkota, Amir (UMD SPH Maryland Institute for Applied Environmental Health)
He, Xin (UMD SPH Epidemiology and Biostatistics)
Kotanko, Peter (Icahn School of Medicine)
Background: Access to health care services and treatment due to weather disturbances are among several challenges that medically fragile populations face. As such, end-stage renal disease (ESRD) patients who receive outpatient dialysis are vulnerable to increased morbidity and mortality due to missing critical treatments. There have been few studies that have characterized the role of severe weather events on hemodialysis (HD) treatment adherence using longitudinal-based patient data across multiple regions.
Goal: The overall goal is to characterize the effects of weather conditions such as precipitation, snowfall, snow depth, and wind on HD missed appointments in selected United States (US) urban northeastern cities: Boston, MA (BOS); New York City, NY (NYC), and Philadelphia, PA (PHL) from 2010 to 2012.
Objectives: We tested a series of hypotheses using varying weather types and exposure metrics (e.g., continuous, occurred/not occurred, and inclement/no inclement) in treatment adherence among patients residing in BOS, NYC, and PHL.
Approach: Daily meteorological data on total precipitation, total snowfall, total snow depth, fastest 2-minute wind speed (WSF2), and fastest 5-second wind speed (WSF5) were extracted through the Global Historical Climatology Network (GHCN). We joined location-specific weather data to HD patient databases with respect to their clinic ZIP codes. Marginal logistic regression models were specified to determine averaged population-level effects for each location. All models were adjusted for age, sex, and pre-existing co-morbidities.
Results: Inclement snowfall days exhibited statistically significant (p<0.05) increased averaged odds for missed appointments in BOS (363%), NYC (70%), and PHL (70%). Inclement rainfall days also exhibited a significant response in PHL (81%), and inclement snow depth days demonstrated significant effects in NYC (91%) and PHL (81%). Patients residing in BOS and PHL demonstrated significant responses to sustained windy conditions (WSF2), whereas only PHL exhibited a significant response to missed appointments from storm-driven gusty winds (WSF5).
Importance to public health: Inclement weather conditions demonstrated a potential role in discouraging treatment adherence among hemodialysis patients. As such, dialysis centers and local health services could consider using weather forecasting to anticipate location-specific missed appointments and trigger appropriate preparedness to help shuttle HD patients and manage possible overflow following the weather event.
Sandhu, Avinaash Kaur (UMD CMNS Cell Biology and Molecular Genetics)
Background: Although many studies have documented the pollution in the Yamuna, few have studied the extent of the pollution in groundwater sources. The potential presence of groundwater pollution poses an imminent public health risk because many socio-economically lower families depend on it as a source of potable water, and often consume it without considering the potentially serious health hazards.
Goal: This research project aimed to clarify the degree of groundwater pollution present in two areas of North Delhi (India): Daulat Ram College and Majnu Ka Tila, by using zebrafish embryos as biosensors.
Objectives: The goal of this study was to observe any developmental defects present in the zebrafish embryos after exposure to sample water. According to previous research performed on pollution in the Yamuna, and the various developmental defects associated with it, the hypothesis was as stated: "Owing to the widespread pollution in the Yamuna, and the fact that these groundwater sources contain water originating from the river, there is a strong possibility of percolated pollution present in groundwater. This pollution would have detectable impacts on organisms exposed to it that may be observed with microscopes and/or other technology."
Approach: Zebrafish embryos were exposed to the sample water for a period of 12 days post fertilization (dpf) (with embryos exposed to System Water functioning as a control group) and were examined for deformities found previously in research studies studying populations living near the Yamuna. A 6 well plate was used with 3 samples -- System water (control), Majnu Ka Tila water, Daulat Ram College water, and a replicate for each sample. Embryos were examined on a daily basis and were photographed for documentation and comparison. Embryos were fed with paramecium after 6 dpf to account for the depletion of the yolk. To document any and all deformities, embryos were photographed under an EVOS microscope from 5 dpf to 12 dpf. These were then compared to photographs of control embryos for analysis.
Results: Although this was a purely phenotypic analysis, significant evidence of deformities was found in the zebrafish exposed to the sample water; the results indicated a significant degree of groundwater pollution in these two sources, implying that other groundwater may also be seriously polluted as well. This research will be followed up on this summer, where chemical analysis of the water will be conducted, and further plans will be developed to build on the conclusion from the initial study.
Importance to public health: Due to advertising and "purity" associated with groundwater, populations in poverty-ridden areas consume this water without any safety precautions. As previous research has not been able to correlate the possibility of developmental defects to groundwater pollution, the water authorities have not made any changes to their current routine and/or publicized the issues connected to groundwater. This research aims to provide the evidence needed to enact that policy change.
Tai, Sheldon (Maryland Institute of Applied Environmental Health)
German, Jennifer (Maryland Institute of Applied Environmental Health)
Milton, Don (Maryland Institute of Applied Environmental Health)
Background: C.A.T.C.H. (Characterizing and Tracking College Health) investigates infectious respiratory diseases and what makes an individual contagious. C.A.T.C.H. looks at how several factors, such as contacts, the infectious agent, and the environment, impact susceptibility.
Goal: The goal of this substudy is to quantify pathogenic copies of respiratory viruses in participants.
Objectives: In particular, the research objective is to create standard curves for specific pathogens.
Approach: To successfully do so, a serial dilution is used to create different concentrations of viral pathogen samples. The dilutions are analyzed using RT-qPCR, which multiplies the number of sample copies. The RT-qPCR creates the standards curves with Ct values that are then used to quantify virus copies.
Results: It is expected that the respiratory viruses analyzed will result in standard curves to retroactively quantify viruses from participants of the C.A.T.C.H. study.
Importance to public health: By better understanding the concentrations of viruses, the standard curves developed can not only be applied for more efficient sample processing in the future, but also provide context about the relationship between factors like BMI, gender, and past vaccinations to viral shedding.
Milton, Donald (UMD SPH Maryland Institute for Applied Environmental Health)
Tai, Sheldon (UMD SPH Maryland Institute for Applied Environmental Health)
Background: C.A.T.C.H. (Characterizing and Tracking College Health) is designed to seek biomarkers of contagiousness in those who have been exposed to Acute Respiratory Infection (ARI). C.A.T.C.H. looks at several factors, which includes direct contacts, indirect contacts (fomites), and living conditions (shared air space), to find out what drives transmission of ARI.
Goal: The goal is to create a standard curve that can be made to quantify viral shedding from a participant, which will be used to assess the social and physical environmental influences, health behavior, and influence of co-infection for ARI contagion.
Objectives: The research objective of this study is to clone the PCR fragments from the viral assays of the Taqman array card, which will be used to create a standard curve that will quantify viral shedding in the C.A.T.C.H study samples.
Approach: The PCR fragment was ligated with the vector pGEM-T Easy and transformed into bacteria by heat shock. Next, the plasmid DNA was isolated from bacterial culture through minipreparation and verified by restriction digestion and sequencing.
Results: PCR amplicons from Coronavirus (COV OC43, COV NL63, COV 229E, and COV HKU1), Respiratory Syncytial Virus (RSV A and RSV B), Influenza A H3N2, and Adenovirus were successfully cloned, verified, and used for establishing the standard curve.
Importance to public health: The results, quantity of viral shedding from a participant of the C.A.T.C.H. study, will help us understand the shedding and transmission of respiratory viruses, which will help identify biomarkers of contagiousness to a certain disease. This will reduce the spread of respiratory diseases and pandemic risk.
Pinto, Nelson (UMD CMNS Biochemistry)
Gold, Louie (UMD SPH Public Health Science)
Sukhavasi, Roohali (UMD SPH Public Health Science)
Shi, Christine (UMD SPH Public Health Science)
German, Jennifer (UMD SPH)
Background: Based on previous focus assays, identifying whether or not a virus was in a cell was unclear. By conducting this project, we can identify better immunofluorescent dyes to differentiate between infected cells and uninfected cells.
Goal: The purpose of the project is to perfect the focus assay.
Objectives: By using immunofluorescent dyes and using different cell staining work on MDCK (Madin-Darby Canine Kidney) cells, we will be able to determine the best staining for future focus assays.
Approach: Students conducted focus assays using MDCK (Madin-Darby Canine Kidney) cells, which were cultivated for several weeks, to study antibody response to influenza A. MDCK cells were selected for their unique susceptibility to influenza virus and the relative inexpensive nature of these cells. Due to this increased susceptibility to influenza virus and ease of cultivation, differentiating the MDCK cells from the sample cells is more efficient.
Results: We are currently testing the dilutions of E-cadherin and cross reacting anitbodies.
Importance to public health: Further developing focus assays, will allows us to better analyze and isolate infectious virus from breath samples.
Weisman, Hannah (UMD SPH Maryland Institute of Applied Environmental Health)
Background: Acute Respiratory Infections (ARI) have been detrimental to society for centuries. While research has come a long way, the annual influenza epidemic persists indicating our poor understanding of ARI transmission. The Characterizing and Tracking College Health Study (C.A.T.C.H. Study) will help aid scientists to a better understanding of ARI contagiousness.
Goal: The goal of the C.A.T.C.H. Study is to identify biomarkers that can indicate which individuals are likely to become contagious and spread ARI to others and to ultimately improve our understanding of ARI transmission.
Objectives: 1. To collect samples from sick participants to determine the pathogen causing their illness and identify biomarkers of infection. 2. To follow the case’s close contacts for up to seven days and track their biomarkers of infection to see if they contract the same infection from their case.
Approach: The C.A.T.C.H. Study took participants from two cohorts: 1) The Index Cohort including freshmen living in the Cambridge Community who are in the Life Sciences (LS), Global Public Health (GPH), and Science Technology and Society (STS) Scholars programs and those students’ roommates. 2) The Main Cohort - the remainder of students living in the Cambridge Community and the freshmen who are in LS, GPH, and STS but live outside the Cambridge Community. Participants were taken as sick cases or close contacts and were tested accordingly.
Results: We have conducted 41 case visits with 18 cases positive for one of the four ARI of interest (Influenza, Adenovirus, Coronavirus, and Respiratory Syncytial Virus (RSV)). From those 18 cases, 10 were infected with Coronavirus, 4 with Flu-A, 2 with Flu-B, and 3 with RSV-B. One case had both Flu-A and RSV-B concurrently. We followed 40 close contacts of the 18 individuals with positive ARI tests. 7 of those contacts became sick with the same virus as their case. Further analysis of samples and biomarkers will help us understand more on the transmission of ARI.
Importance to public health: With an improved understanding of what contributes to and impacts contagiousness, we may better prepare for and even prevent future epidemics and pandemics of influenza or other ARI.
Zambrana, Jordan (UMD SPH Maryland Institute for Applied Environmental Health)
Blythe, David (Prevention and Health Promotion Administration)
Mitchell, Clifford (Prevention and Health Promotion Administration)
Sapkota, Amy (UMD SPH Maryland Institute for Applied Environmental Health)
Sapkota, Amir (UMD SPH Maryland Institute for Applied Environmental Health)
Background: Salmonella infections cause 19,000 hospitalizations and 380 deaths on a yearly basis in the United States. Previous studies have linked higher temperature, including extreme heat events with greater risk of foodborne illness. However, there is a paucity of data regarding how extreme weather events impact risk of Salmonella infection across the United States, and how these risk is modified by large scale weather phenomenon such as El Nino Southern Oscillations (ENSO).
Goal: To understand the critical role extreme heat and precipitation events associated with climate change in concert with increased vulnerability of persons of lower socioeconomic status play in the rate of foodborne illness.
Objectives: 1.To investigate the association between exposure to extreme weather events and risk of Salmonella infection across the 10 Food Net states. 2.Explore how this risk varied across Salmonella serotypes and socio-demographic characteristics
Approach: We merged the Foodborne Diseases Active Surveillance Network data (2002-2012) from 10 states, with extreme weather event data for the same period computed using 1960-1989 as the baseline. We used negative binomial generalized estimating equations to investigate the association between exposure to extreme weather events and risk of Salmonella infection across the 10 states, and explored how this risk varied across socio-demographic characteristics. We further stratified the analysis by phases of ENSO (El Nino, La Nina and ENSO neutral).
Results: Our results show that extreme heat events are associated with an increased risk of Salmonella infection, however the risk vary considerably across the 10 Food Net states. Across all states, the risk of Salmonella infection was higher during El Nino and La Nina compared to ENSO neutral periods. When we stratified the analysis by serotype (enteritdis, javiana, newport and typhimurium), we observed considerable variability in extreme event related risks across different serotypes. We further observed that coastal states were at increased risk compared to non-coastal states.
Importance to public health: Our results show that extreme weather events are associated with salmonellosis in the United States and that the risk varies across geographic region, demographic characteristics and phases of ENSO. Location specific adaptation strategies incorporating such variability in risk are needed to minimize the future burden of food and waterborne illnesses associated with extreme weather events.