Digital Commons Network^™

Using The Behavior Change Wheel To Understand The Role Of Antimicrobial Stewardship Programs, Siqi Jiang

Public Health Theses

Objectives: This review aimed to summarize recent antimicrobial stewardship programs (ASPs) implemented in pediatric outpatient settings and analyze how these interventions influence appropriate antibiotic use.Methods: PubMed and Scopus were searched for studies published between 2016 and 2026 globally. Studies were included if they evaluated an antimicrobial stewardship intervention in a pediatric outpatient setting. Only English studies are included. Studies that describe the results of implementations and policies related to ASP are included, including randomized controlled trials, quasi-experiments, natural experiments, quality improvement studies and observational studies, and longitudinal studies. Interventions in selected articles were analyzed using the COM-B (Capability, Opportunity, Motivation-Behavior) …

Family-Related Stressors And Mental Health Among Internally Displaced Young Adults In Mozambique: A Mixed-Methods Study With Implications For Global Mental Health Interventions, Jaspreet Kandola

Public Health Theses

Mental health outcomes among displaced populations are shaped by post-displacement stressors, yet the role of family dynamics, specifically, remains insufficiently understood. This study examines how family-related stressors are associated with mental health among internally displaced young adults in Nampula Province, Mozambique. Using a convergent parallel mixed methods design, this study integrated survey data from 601 participants with qualitative data from in-depth interviews with a subsample of 16 participants. Quantitative analyses showed that family separation and concern for family members in conflict zones were associated with higher posttraumatic stress disorder (PTSD) symptoms, with family separation also linked to higher anxiety and …

Kinetics Of Antibody Responses To Hookworm Excretory/Secretory Products In A Hamster Model Of Infection And Cure, Jacquelyn Kauffman

Public Health Theses

Hookworms are a major global health burden in resource-limited settings despite ongoing control programs. This makes understanding host immune responses to infection and treatment critical to improve diagnostics and interventions. This study investigates the long-term kinetics of antibody responses following infection with Ancylostoma ceylanicum in a hamster model. Over a one-year study, groups of six hamsters were assigned to uninfected, infected, or infected then treated groups, with antibody responses measured using ELISAs. All infected animals had elevated IgG, IgM, and IgA responses by day 21 post infection. Mebendazole-treated hamsters had significantly reduced, but not eliminated, antibody levels, with IgM responses …

Nowcasting Dengue Cases In Poor Surveillance Nations Using Meteorology And Climate-Similar Countries, Hanna Kim

Public Health Theses

Dengue fever poses a growing public health burden across the Caribbean, yet surveillance infrastructure remains inconsistent and timely outbreak detection in data-poor nations becomes limited. This study investigates whether shared meteorological patterns between Caribbean countries can be leveraged to nowcast dengue activity in low-surveillance settings using climate-matched, well-surveilled nations as epidemiological proxies. Weekly and monthly dengue case data for six countries, the Dominican Republic, Jamaica, Puerto Rico, Trinidad and Tobago, Cuba, and Haiti, were extracted from the OpenDengue database for 2005–2024, and satellite-derived climate data were obtained from the NASA POWER API. Pairwise climate correlations revealed strong temperature synchrony across …

Indoor Environmental Quality Perceptions And Self-Reported Symptoms Among West Haven Va Healthcare Employees, Joseph Hyong Kim

Public Health Theses

Background: Indoor environmental quality in workplace settings influences worker well-being, yet the relationship between perceived workplace environment and reported symptoms remains less well characterized in heterogeneous healthcare settings. This study describes perceived workplace environmental quality and self-reported symptoms among employees at the West Haven Veterans Affairs (VA) Medical Center.

Methods: An observational, cross-sectional study was conducted of VA employees across clinical and non-clinical roles to assess perceived work environment, symptoms and indoor exposures using an electronic survey and personal and area air monitoring of indoor volatile organic compounds (VOCs) and viruses. Perceived workplace environmental quality was assessed using the MM-40 …

Pediatric Rheumatic Heart Disease Screening For Secondary Antibiotic Prophylaxis: An Explainable Shannon Energy Approach Using Heart Phonocardiogram In Northeast Brazil, Zhuohui Lin

Public Health Theses

Rheumatic Heart Disease (RHD), caused by Group A Streptococcus (GAS), remains a significant global health burden, particularly among children in low- and middle-income countries. Untreated GAS infection can lead to acute rheumatic fever and subsequent chronic valvular damage of RHD, such as mitral valve (MV) regurgitation. Hence, early detection is critical for the administration of Secondary Antibiotic Prophylaxis to prevent disease progression. Although deep learning models demonstrate high diagnostic accuracy, limited explainability restricts clinical adoption, especially in resource-limited settings. In this proof-of-concept study, we evaluated Shannon energy (SE) transformation as a proxy to differentiate holosystolic murmurs associated with RHD-related mitral …

Climate, Land Use, And Lyme Disease Risk In The United States, Mohan Li

Public Health Theses

Lyme disease is the most common vector-borne bacterial infection in the United States. It remains an important public health concern due to its high disease burden, expanding geographic distribution, and complex transmission cycle. Climate change is frequently regarded as a driver of Lyme disease emergence, as many previous studies suggested. However, ongoing debate about the magnitude and mechanisms of climate effects complicates the interpretation of this relationship. This review synthesizes evidence on how climate influences Lyme disease through both direct and indirect pathways, with a focus on studies relevant to the United States and North America.Climate directly affects Lyme disease …

Optimizing Positivity Cutpoints Using Validated Assessment Tools For Osteoporosis And Sarcopenia In Aging People Living With Hiv In Peru, Joselito Malca Hernandez

Public Health Theses

AbstractBackground: People living with HIV (PWH) are at increased risk of osteoporosis and sarcopenia, yet access to gold-standard diagnostic tools remains limited in many settings. Low-cost screening tools such as OST, SCORE, and SARC-F offer practical alternatives, but optimal cutpoints and their implications for clinical decision-making in PWH are not well defined.

Methods: We conducted a secondary analysis of cross-sectional data from 229 PWH aged ≥45 years receiving care in Lima, Peru. Osteoporosis was defined using DXA among postmenopausal women and men ≥50 years, and sarcopenia using AWGS-2019 and EWGSOP2 criteria. We evaluated the diagnostic performance of OST, SCORE, their …

Maternal Sleep, Sleep Medication Use, And Birth Outcomes: A Pilot Study Of The Pregnancy, Environment, And Child Health (Peach) Cohort, Samantha Lydell

Public Health Theses

Pregnancy is often a period of poor sleep quality. Previous research has linked reduced sleep quality and difficulty sleeping during pregnancy to adverse maternal and fetal outcomes. However, little is known about how sleep medication use may influence these associations. This pilot study examines the relationships between poor sleep, sleep medication use, and birth outcomes in the Pregnancy, Environment, and Child Health (PEACH) cohort. This study included 136 participants from the PEACH cohort linked to Yale New Haven Health delivery records. Poor sleep and sleep medication use were self-reported. Outcomes were gestational age at birth (days) and birth weight (grams). …

Understanding The Influence Of Hiv Status On Perceived Barriers To Reproductive Care For Pregnant Haitian Women: A Framework-Guided Qualitative Analysis, Olivia Mccarthy

Public Health Theses

Background: Haiti has the highest maternal mortality rate in Latin America and the Caribbean, where pregnant women face substantial structural, social, and economic barriers to care. Women living with HIV encounter additional challenges, including stigma, breaches of privacy, and discrimination within healthcare settings. Although prior research has examined maternal health and HIV related stigma in Haiti, little is known about how HIV status differentially shapes pregnant women’s perceptions of barriers to maternal healthcare.Methods: This study draws on data from seven focus groups conducted in rural communities in Haiti’s Centre Department between 2018 and 2019. Participants included 65 pregnant women, representing …

Telehealth Adaptation Of Bright Bodies Program, A Pediatric Intensive Lifestyle Intervention For Obesity: Caregiver Experiences And Implications For Future Implementation, Xiayu "Katniss" Ni

Public Health Theses

Introduction: The Virtual Bright Bodies Program is a telehealth adaptation of Yale's evidence-based family-based intensive lifestyle intervention targeting pediatric obesity, delivered through video conferencing during and following the COVID-19 pandemic. This retrospective cross-sectional study evaluated caregiver experiences with the telehealth-adapted program among 25 caregivers of children aged 7-16 years who completed a post-program survey.

Method: Caregiver perceptions were assessed using the adapted Telehealth Satisfaction Questionnaire (TSQ, 13 items), the adapted Telemedicine Satisfaction and Usefulness Questionnaire (TSUQ, 4 items), and the Acceptability of Intervention Measure (AIM, 4 items). Quantitative data were analyzed descriptively, followed by exploratory subgroup analyses examined whether acceptability …

Successive Blood Meal Feeding And Wolbachia Impact On The Intra-Host Genetic Diversity Of Dengue Virus In Aedes Aegypti Mosquitoes, Braiya Nolan

Public Health Theses

Dengue virus (DENV) is a mosquito-borne RNA virus and increasing public health threat. Due to its error prone replication, single-nucleotide variants (iSNVs) are rapidly generated within the vector, leading to heterogeneity in viral populations, fitness, virulence, and transmissibility, including under vector control interventions. One such control strategy is the large-scale deployment of Wolbachia-infected mosquitoes worldwide. Wolbachia is an endosymbiotic bacterial biocontrol method that provides incomplete inhibition of DENV replication and transmission. Given its incomplete inhibition, it is critical to understand how Wolbachia impacts DENV-2 intra-host viral diversity. Additionally, successive blood meal feeding may influence intra-host viral diversity by supporting increased …

Triangulating Clinical Guideline Recommendations To Map The Standard Of Care For Hypertensive Disorders Of Pregnancy During Pregnancy And Postpartum, Caralie Price

Public Health Theses

Hypertensive disorders of pregnancy (HDP) are one of the leading causes of maternal morbidity and mortality in the United States. HDP represent a severe health equity issue and present concerns for the health of mother and child, highlighting the importance of early detection and management. This paper systematically documented current clinical practice guidelines from the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) for preventing, identifying, and treating HDP during the prenatal, intrapartum, and postpartum periods. ACOG provides recommendations for HDP across different types of clinical guidance documents. Overall, 60 recommendations were extracted across …

Characterization Of Tick Exoproteins Interacting With Anaplasma Phagocytophilum, Yilei Qin

Public Health Theses

Anaplasma phagocytophilum (Ap) is an Ixodes-transmitted obligate intracellular bacterium thatinfects neutrophils and causes human granulocytic anaplasmosis. Ap alternates between an infectious dense-cored (DC) form and a replicative reticulate cell (RC) form, and successful transmission depends on coordinated interactions at the vector–pathogen interface. Tick extracellular and secreted proteins (the tick exoproteome) likely contribute to Ap survival and transmission, yet many proposed tick factors remain computationally annotated with limited experimental validation. In this thesis, I prioritize candidate tick exoproteins, identified from yeast- display screens using whole Ap organisms, and evaluate them using a two-step validation strategy. First, I quantify tissue-specific expression of …

Protecting Older Individuals From Age Discrimination Harming Psychological Well-Being: Role Of Neighborhood Cohesion, Tongyu Qiu

Public Health Theses

Age discrimination is known to harm older adults’ mental health, yet factors that may protect against this harm have received little attention. Prior studies have focused primarily on individual-level factors rather than community-level characteristics, such as neighborhood cohesion, which may be more amenable to large-scale interventions and policies. To our knowledge, no prior study has examined whether neighborhood cohesion buffers the association between age discrimination and worse psychological well-being in older adults. Participants aged 60 years and older were drawn from the Midlife in the United States (MIDUS) study. We hypothesized that baseline age discrimination would predict worse psychological well-being …

Invasive Pneumococcal Disease: Outcomes And Vaccine Effectiveness By Risk Profiles Among A Pediatric Cohort From 2002 – 2025, Keyner Rojas

Public Health Theses

AbstractBackground: Invasive pneumococcal disease (IPD) remains a significant cause of morbidity and mortality among children globally, despite the widespread use of protein conjugate vaccines (PCVs). While the introduction and implementation of these vaccines have drastically reduced the incidence of vaccine-type invasive disease, shifts in circulating serotypes raise concerns of serotype replacement. Methods: This study is a retrospective observational study of pediatric IPD cases in Massachusetts from 2002 – 2025. Over the course of these 23 years, the Massachusetts Department of Public Health has operated an enhanced population-based, statewide surveillance system for IPD. Isolates of Streptococcus pneumoniae from normally sterile sites …

Status, Inclusion, And Self-Esteem In Daily Life: Examining Moderation By Social Anxiety, Dylan Schnur

Public Health Theses

Prior work has shown a distinct pattern in how social feedback shapes self-belief and self-esteembetween individuals with and without social anxiety disorders (SAD). EMA-type studies have proven to be valuable because these types of studies can capture differences in cognition, health, and behavior across forms of psychopathology between- and within individuals. To our knowledge, no prior studies akin to EMA have examined between- and within-person associations of status and inclusion on self-esteem and moderation by social anxiety when positive and negative feedback, regarding these traits, are experienced. Across this 21-day ecological momentary assessment study, participants (N = 175, 12,021 observations) …

Perceptions Of Sexual Health Stigma Among Adolescents And Pediatric Primary Care Providers In The United States: A Qualitative Exploration, Avanti Shah

Public Health Theses

Background: In the United States (U.S.), young people aged 13–24 experience disproportionately poor sexual health outcomes. Sexual health stigma has been identified as a key barrier to uptake of sexual health services (e.g., STI/HIV testing), particularly for adolescents younger than age 18. This study aimed to describe and compare how U.S. adolescents and pediatric primary care providers perceive sexual health stigma and its potential influence on adolescent sexual health service access and utilization.

Methods: The study utilized existing data from two qualitative studies that explored pediatric primary care providers’ awareness of state laws regulating minors’ access to confidential sexual health …

Compromised Glutathione And Ascorbate Capacities Under Prenatal Alcohol Exposure, And Its Implications For Vulnerable Subpopulations, Reagan Strand

Public Health Theses

Prenatal alcohol exposure (PAE) remains the leading preventable cause of lifelong neurodevelopmental impairment, yet the biological mechanisms underlying differential susceptibility remain poorly understood. The populations most vulnerable to PAE overlap substantially with those bearing the greatest burden of antioxidant insufficiency, including individuals experiencing food insecurity, environmental pollutant exposures, and alcohol use disorder, yet this convergence and its developmental consequences remain poorly characterized. This thesis investigates how dual antioxidant deficiency in both the dam and offspring modulates vulnerability to PAE using a compound heterozygous mouse model (GclmHET/GuloHET) that recapitulates reductions in antioxidants glutathione (GSH) and ascorbic acid (AA, or Vitamin C) …

Vibriosis In Connecticut: Case Trends And Seasonality, 1997–2024, Lisa Michelle Stutzman

Public Health Theses

Vibrio bacteria species, including V. vulnificus and V. parahaemolyticus, cause vibriosis, which can present as gastrointestinal illnesses, wound infections, or septicemia. In the United States the geographical range of these infections is growing, with the northward expansion of Vibrio along the Atlantic coast highlights the importance of understanding trends in vibriosis in Connecticut. This analysis is based on surveillance data from the Connecticut Emerging Infections Program from January 1, 1997–December 31, 2024. Analyses were restricted to culture-confirmed cases to ensure consistent case definitions and conducted on data aggregated to the state level. Descriptive statistics were used to characterize trends in …

Effectiveness Of The Release Of Wmel Wolbachia-Infected Aedes Aegypti Mosquitoes On The Incidence Of Chikungunya In Campo Grande, Brazil, Vivienne Zhong Ying Su

Public Health Theses

Chikungunya is a mosquito-borne arboviral disease primarily transmitted by Aedes aegypti and Aedes albopictus that is rapidly emerging in new geographical settings because of climate change, viral adaptation, and globalization. Brazil has experienced the significant expansion of chikungunya over the past decade and has adopted novel vector control interventions, including Wolbachia-based population replacement, as part of its public health response. While the effectiveness of wMel Wolbachia on dengue incidence has been demonstrated across multiple settings, evidence on its effect on chikungunya risk remains limited. Large-scale releases of wMel-infected Aedes aegypti mosquitoes were implemented in the city of Campo Grande, Brazil …

Modeling Pfoa And Pfos Infant Intake Through Breast Milk And Formula In The United States, Ka Hei Tang

Public Health Theses

Background: Per- and polyfluoroalkyl substances (PFAS), including PFOA and PFOS, may reach infants through breast milk and water used to reconstitute infant formula. However, current U.S. evidence is limited, and the absence of nationally representative breast milk PFAS data constrained estimation of early-life infant exposures.Methods: This thesis developed a state-level exposure modeling framework to estimate daily infant PFOA and PFOS intake across U.S. states at 3 and 6 months of age. Modeled intake included two feeding pathways, breast milk and formula-reconstitution water, using national maternal serum PFAS concentrations, state-level public drinking water PFAS concentrations, and infant feeding distributions. A total …

Redefining Hospital-Acquired Rsv: Epidemiologic Burden And Probabilistic Classification In A Large Health System, Anna Trinh

Public Health Theses

Healthcare acquired respiratory syncytial virus (HA RSV) is an important but under recognized infection in adult patients. Current surveillance definitions classify RSV as healthcare acquired when a positive test occurs ≥48–72 hours after admission, despite a broad incubation period of 2–8 days which would allow community acquired infections to present several days into hospitalization. This thesis has two aims: (1) to describe the epidemiology of adult HA RSV cases in the Yale New Haven Health System (YNHHS) from 2021–2025, and (2) to develop an incubation period-based probabilistic model to assess the plausibility of each HA RSV classification. Among 2,905 laboratory-confirmed …

Influenza-Associated Hospitalizations And Socioeconomic Status In Southern Connecticut, 2022-2025, Allison Traiger

Public Health Theses

Background: Influenza is a common respiratory illness in the United States responsible for hundreds of thousands of influenza-associated hospitalizations each year. To implement effective preventative interventions, it is crucial to understand which populations are most at risk of severe illness and hospitalization. Prior studies have found that increased rates of poverty and crowding are associated with increased rates of hospitalization.Methods: This study explores the connection between neighborhood poverty, crowding, and influenza-associated hospitalization through the connection of hospitalized influenza cases with their census tract-level socioeconomic indicators. Addresses of hospitalized cases were geocoded and linked to data on poverty and crowding from …

Trends And Prevalence Of Autism Among Asian American Subgroups In California, Qinyue Wang

Public Health Theses

AbstractBackground: Autism spectrum disorder (ASD) affects a growing number of children in the United States (US), yet substantial heterogeneity in its remains poorly understood. While previous studies have identified racial and ethnic disparities in ASD prevalence, the Asian American population is frequently treated as a single, monolithic group. This aggregation masks critical variation across distinct Asian ethnic subgroups, potentially obscuring unique barriers to diagnosis and care. This analysis aimed to investigate trends in ASD by age 6 among seven distinct maternal Asian subgroups born between 2007 and 2015 in California and evaluate the influences from maternal demographic factors and neighborhood-level …

From Genomic Surveillance To Vaccine Efficacy: Assessing The Impact Of Plasmodium Falciparum Rh5 Genetic Diversity On Blood-Stage Malaria Vaccine Performance, Xinyan Wei

Public Health Theses

Malaria remains a major public health burden in sub-Saharan Africa. The development and deployment of effective malaria vaccines is a priority for reducing disease burden and severe outcomes. The protective immunity generated by current malaria vaccines declines over time, requiring booster doses to sustain efficacy. Consequently, next-generation malaria vaccines are under development, including a blood-stage vaccine targeting reticulocyte-binding protein homolog 5 (RH5), the most advanced candidate in clinical development. This study investigates whether genetic diversity in PfRH5 may influence vaccine efficacy using amplicon sequencing and bioinformatic analyses across three complementary approaches. Firstly, this study characterizes PfRH5 genetic diversity across multiple …

Physical Therapy And Length Of Inpatient Stay In Relation To Neuropsychological Functioning Among Childhood Cancer Survivors: A Retrospective Cohort Study From The Heros Registry, Jingyi Zhang

Public Health Theses

Background: As 5-year survival after childhood cancer exceeds 85%, neuropsychological late effects have emerged as a key issue. Despite this, the impact of modifiable risk factors during cancer treatment on subsequent neuropsychological outcomes remains obscure. This study aimed to evaluate whether physical therapy (PT) and length of inpatient stay are associated with later neurocognitive, emotional, and behavioral outcomes in childhood cancer survivors (CCS).Methods: This study included 92 CCS who had available electronic health records (EHR) for cancer treatment and completed a neuropsychological evaluation 0–5 years after their treatment end date. Information on PT and length of inpatient stay (i.e., the …

Medicaid Expansion And Two Pathways To Hpv Prevention: A State-Level Analysis Of Vaccination Coverage And Cervical Cancer Screening, Yiting Yin

Public Health Theses

Human papillomavirus (HPV) vaccination and screening are the two primary strategies for preventing HPV-associated cervical cancer, yet progress toward national coverage goals remains uneven. The Affordable Care Act’s Medicaid expansion, adopted by states on a staggered timeline since 2014, is a major policy lever for reducing barriers to preventive care, but its association with HPV-related prevention has not been examined across both services in a unified framework.

This thesis uses a state-level ecological design to examine the association between Medicaid expansion status and two outcomes: (1) HPV vaccination coverage among adolescents aged 13 to 17 (NIS-Teen, 2012–2024), measured as series …

Assessing Cardiovascular Disease Risk And Healthcare Access Barriers To Identify Prevention Strategies Among Market Vendors In Uganda, Yumi Yang

Public Health Theses

Background: Cardiovascular disease (CVD) accounts for 10% of all deaths in Uganda, making it the leading cause of death among non-communicable diseases (NCDs) in the country. Across sub-Saharan Africa, urban market vendors serve as key participants in the informal workforce. Research from West Africa suggests that vendors, many of whom are women, are a vulnerable population with high prevalence of CVD risk factors and structural barriers to healthcare access. However, limited research has examined this population in East Africa, and the present study is the first to characterize 10-year CVD risk and assess healthcare barriers among market vendors in Uganda.Methods: …

Asymptomatic Tb Duration And Transmission Models, Zhichao Zhou

Public Health Theses

Tuberculosis (TB) transmission is sustained in part by asymptomatic disease states that limit the effectiveness of passive case finding interventions that rely on symptom-based diagnosis. Here we develop a transmission model that represents the duration of asymptomatic disease with a gamma-distributed waiting time. By chaining multiple asymptomatic sub-states, we find that the gamma-distributed model provides a better fit to the observed distribution of the duration of asymptomatic disease than a simple one-state model which imposes an assumption of an exponentially-distributed duration of asymptomatic disease. Comparing the fitted gamma-distributed model and the simple model, we quantify how assumptions about the distribution …