Digital Commons Network^™

Assessing The Costs Of Illness Attributable To Leptospirosis, Alyssa Chetrick

Public Health Theses

Leptospirosis, caused by the spirochetes of the genus Leptospira, is a zoonotic bacterialdisease endemic to tropical regions and lower middle income countries (LMICs). Leptospirosis causes an estimated 1 million cases and more than 58,900 deaths annually.(Costa et al., 2015; Torgeson et al., 2015) In addition to human health, leptospirosis significantly impacts animal health and the livestock industry, particularly through reproductive losses, increased treatment costs, and decreased milk production, which exacerbates global insecurity.(Bennet, 2015; Torgeson et al., 2015) The estimated global cost loss to productivity due to disease is estimated at Int$ 29.3 billion. (Agampodi et al., 2023) Because of its …

Scale-Up Of Access To Medication For Opioid Use Disorder For People Who Inject Drugs On Parole In Ukraine: A Modeling Analysis, Brendan Caver

Public Health Theses

Background: Human Immunodeficiency Virus (HIV) and opioid-use disorder have long beendescribed as a syndemic; the two health issues go hand-in-hand to exacerbate each other (Perlman & Jordan, 2018). While the HIV pandemic has improved greatly in many regions such as the United States over the past several decades, it continues to become worse in Eastern Europe and Central Asia. HIV prevalence and opioid dependence are particularly high in carceral settings, but access to opioid agonist therapy (OAT) is extremely limited. This paper shows the results of a modeling analysis undertaken to see the impact of opioid agonist therapy (OAT) scale-up …

The Impact Of Climate Change On Japanese Encephalitis Trends In China, Jiayi Du

Public Health Theses

Japanese encephalitis (JE) is a mosquito-borne viral disease that poses a significant public health threat across Asia, including China. Climate change has been increasingly recognized as a key driver of JE transmission dynamics, influencing mosquito vector distribution and virus proliferation. This study aimed to assess how climatic variables affect the ecological suitability for Japanese encephalitis virus (JEV) transmission, using species distribution modeling with MaxEnt.

Using climate data from WorldClim and JE incidence data from published sources, we applied the MaxEnt model to identify the key environmental predictors of JE transmission and project future risk areas under changing climatic conditions. The …

Exploring Harm Reduction In Treatment: A Qualitative Study Of Methods And Perceptions Among People In Substance Use Disorder Care, Carson Francis Ferrara

Public Health Theses

Amidst the ongoing opioid epidemic and rising overdose deaths, substance use disorder (SUD) treatment has historically prioritized abstinence over harm reduction, creating gaps in patient safety. This qualitative study explores harm reduction integration in formal treatment settings and participant perceptions through 48 semi-structured interviews with individuals enrolled in Project RENEW, a larger cohort study examining factors influencing people in treatment for alcohol use across Connecticut and Georgia. Participants (79% inpatient, 51% court-mandated) described their experiences with harm reduction methods and safety strategies while in treatment. Thematic analysis revealed four key findings: 1) inconsistent access to resources like naloxone and fentanyl …

Secondhand Smoke Exposure And The Risk Of Tuberculosis In Children: A Systematic Review And Meta-Analysis, Cenyun Guan

Public Health Theses

ABSTRACT

Introduction: Tuberculosis (TB) remains one of the leading causes of death globally, with children and young adolescents having a significant burden of the disease. Smoking is a well-established risk factor for TB, but the association between secondhand smoke (SHS) exposure and TB remains inconclusive. Pediatric populations are commonly exposed to SHS due to living with smokers in their households. Inconsistencies in the findings of previous systematic reviews on the associations between SHS exposure and TB status (infection and disease) highlight the need for an updated systematic review to better establish these associations and provide evidence-based guidance for reducing the …

Black Lives Matter Paterson’S Harm Reduction Center Program Evaluation, Shreya Jadhav

Public Health Theses

BackgroundThe Substances and Sexual Health (SASH) Lab at the Yale School of Public Health conducts much of its work in Paterson, New Jersey. As part of a community partnership, the lab collaborated with Black Lives Matter (BLM) Paterson to conduct a program evaluation of BLM Paterson’s Harm Reduction Center. BLM Paterson, founded in 2016, offers harm reduction through a wide range of services including survival resources, referrals to treatment, and a touchpoint with the healthcare system, all within a safe, non-judgmental space for individuals to decompress and find support. Evaluation Methods This formative program evaluation assesses the impact of BLM …

Association Between Greenspace And Weight-Related Outcomes In Later Adulthood: A Longitudinal Study Using Uk Biobank Data, Jun Jiang

Public Health Theses

Overweight and obesity are escalating global health concerns, greenspace may support healthierweight, and air pollution may mitigate the effect, but its effects across population subgroups and over time remain underexplored. According to the longitudinal analysis, this study found that greenspace exposure within 300 m was more strongly associated with lower BMI and overweight risk than exposure within 1000 m; for example, the presence of greenspace within 300 m reduced the odds of overweight (OR = 0.791, 95% CI: 0.672–0.933), while the same measure within 1000 m was associated with higher odds of obesity (OR = 1.275, 95% CI: 1.08–1.505). Stratified …

The Evolution And Effectiveness Of Sterile Insect Technique For Vector Control: A Historical And Modern Analysis, Katerina Karaiskos

Public Health Theses

Sterile Insect Technique (SIT) has emerged as an important tool in the control of vector-borne diseases, providing an alternative to traditional chemical insecticides. Initially based on the irradiation of insects to induce sterility, SIT has proven effective in eradication campaigns, including the cases of the screwworm and tsetse fly. SIT’s primary strengths lie in its species specificity, environmental safety, and the avoidance of pesticide resistance. However, “classic” irradiating SIT is limited by high operational costs, reduced mating competitiveness of sterilized males, and difficulties in addressing high-density vector populations. Recent advancements in genetic-based SIT methods, such as the Release of Insects …

Barriers And Facilitators To Covid-19 Vaccination Access Among Older Adults: A Comprehensive Needs Assessment To Enhance Vaccination Strategies, Jiye Lee

Public Health Theses

Objective: To identify system-specific barriers and facilitators to COVID-19 vaccination among older adults (≥65 years) within a large academic healthcare system and to inform future strategies to enhance vaccine uptake.

Methods: This mixed-methods study included six semi-structured interviews with healthcare leaders and staff, a large-scale survey of 42 clinical leaders across 52 ambulatory sites (20 responses), and analysis of administrative data from Yale New Haven Health (2020–2024). Interviews and survey responses were thematically analyzed. Quantitative data on vaccination rates for COVID-19 and influenza were analyzed by age group and year using descriptive statistics and t-tests.

Results: The semi-structured interviews with …

Assessing The Cross-Species Vaccine Potential Of Pfripr Using Transgenic Chimeric Plasmodium Knowlesi Models, Peiqi Li

Public Health Theses

Malaria remains a major global health burden, with an estimated 263 million cases and597,000 deaths reported in 83 countries in 2023 (1). While P. falciparum is responsible for the most severe cases, non-falciparum species such as P. vivax, P. ovale curtisi, P. ovale wallikeri, P. malariae, and P. knowlesi also pose significant public health risks, particularly in co-endemic regions. Current malaria vaccine efforts mainly focus on P. falciparum which is reasonable because over 90% of the global malaria-related morbidity and mortality are caused by P. falciparum (2). However, laying emphasis on targeting P. falciparum leaves a critical gap in cross- …

Influenza Vaccine Coverage, Effectiveness, And Disease Burden Among Pediatric Sickle Cell Patients In Connecticut From 2021-2024: A Test-Negative Case-Control Study, Precious Nchekwube

Public Health Theses

Background: Vaccination is the primary strategy to reduce influenza burden. Limited data exist on the burden of influenza, vaccine coverage, and seasonal influenza vaccine effectiveness (VE) in children and adolescents with sickle cell disease (SCD).

Aim: To evaluate influenza vaccine coverage, effectiveness, and disease burden among pediatric and adolescent patients living with SCD for the 2021-2024 influenza seasons in Connecticut, USA.

Methods: This was a retrospective, test-negative case-control study to estimate influenza VE against laboratory-confirmed influenza infections among children 6 months to 21 years of age across 2021-2022, 2022-2023, and 2023-2024 influenza seasons (August 1, 2021, to July 31, 2024) …

Characterizing The Genetic Diversity Of Pfrh5 In Plasmodium Falciparum Clinical Isolates From Burkina Faso, Ghana, And Tanzania: A Next-Generation Sequencing Study To Inform Blood-Stage Malaria Vaccine Development, Manuel Emilio Perez

Public Health Theses

The development of a highly effective malaria vaccine is of global health priority, given the persistently high malaria burden in Sub-Saharan Africa (SSA) and growing resistance to antimalarial treatment and vector control measures. P. falciparum reticulocyte-binding protein homolog 5 (PfRH5) has emerged as a leading target among blood-stage malaria vaccine candidates due to its essential role in erythrocyte invasion and initial documentation of limited polymorphisms. However, recent studies have revealed greater PfRH5 genetic diversity than previously believed, raising concerns about potential parasite evasion of vaccine-induced immunity. This study utilized deep targeted amplicon next-generation sequencing to characterize PfRH5 genetic variation in …

New Horizons In Hepatitis B Therapy: Antigen Reduction And Immune Modulation Approaches, Yiyun Pan

Public Health Theses

Chronic hepatitis B (CHB) remains a significant global health burden despite advances in antiviral therapy. Current treatments, including nucleoside analogs (NAs) and pegylated interferon (Peg-IFN), effectively suppress viral replication but rarely achieve functional cure, defined as sustained hepatitis B surface antigen (HBsAg) loss. Emerging therapeutic strategies focus on antigen reduction and immune modulation to overcome the limitations of existing therapies.

Antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs) offer promising approaches by directly targeting viral RNA to reduce HBsAg levels. Clinical trials of ASOs such as bepirovirsen and siRNAs such as JNJ-3989 and VIR-2218 have shown substantial HBsAg declines, but …

Effectiveness Of Wolbachia Introgression On Dengue Incidence In A Complex Urban Environment, Karthika Satyanarayanan

Public Health Theses

Dengue is an arboviral disease of increasing global public health importance for which more than half the world’s population is at risk. The burden of dengue has increased greatly in the last decade; in 2024, over 14 million cases and 10,000 dengue-related deaths were reported, marking a historical milestone. The endosymbiotic bacterium Wolbachia (wMel strain) offers a promising alternative to traditional control methods through its reduction of Aedes aegypti vector competence and introgression into wild Ae. aegypti populations. This thesis evaluated the dynamics of Wolbachia introgression and its effect on reducing dengue incidence up to 31 months after the completion …

Assessing Environmental And Sociodemographic Risk Factors For Leptospira Infection In A Urban Informal Settlements: A Study In Salvador, Brazil, Sebastian Alonso Salazar

Public Health Theses

Background: Leptospirosis is a neglected zoonotic disease that disproportionately affects people living in areas with poor sanitation, water contamination and rodent infestation such as urban informal settlements. More than one billion people worldwide reside in such communities, and with increasing urbanization, coupled with environmental change, the risk of Leptospira transmission continues to increase. Despite its global burden, this disease is often underreported due to diagnostic challenges and limited healthcare access, particularly in urban informal settlements. Understanding the incidence and risk factors in these settings is essential for improving public health interventions. This study aims to estimate the annual incidence of …

Impact Of Pcv10 On Pediatric Pneumonia In Nepal, Katie Steimel

Public Health Theses

Pneumococcal conjugate vaccines have significantly reduced pneumonia cases, hospitalizations, and deaths worldwide. This study evaluates the impact of 10-valent pneumococcal conjugate vaccine (PCV10) eligibility on pediatric pneumonia hospitalizations in Nepal using administrative hospital data from three major geographically and administratively diverse hospitals. A controlled interrupted time series design was used comparing pneumonia hospitalizations with diarrhea hospitalizations, under the assumption that PCV10 would not influence diarrhea hospitalization rates. A secondary model stratified hospitalizations by age group, assessing differential trends based on vaccine eligibility. Generalized linear models with quasipoisson distributions were used, adjusting for hospital and seasonality.The primary model comparing pneumonia to …

Disparities In Clinical Trial Representation: Bioethical & Human Rights Violations Against The Global Burden Of Disease And Gender Equity, Kaustubha Reddy

Public Health Theses

This investigative thesis seeks to contribute to the understanding of how disparities in the planning, design, and placement of clinical trials perpetuate global health inequities. It will analyze the misalignment between the global burden of disease and research priorities, examining the systemic factors that determine which diseases are prioritized for trials. It will highlight the bioethical and human rights implications of gender exclusion, particularly the underrepresentation of women with HIV, in clinical research. By addressing both the upstream determinants of clinical trial planning and the downstream consequences of exclusionary practices, this work offers a comprehensive critique of the structural inequities …

Under-Five Malaria And Malnutrition Syndemic In Rajasthan, Nandini Sinha

Public Health Theses

Background: The syndemic of severe acute malnutrition (SAM) and malaria in under-five children in Rajasthan presents a critical public health challenge. Current SAM and malaria programs are implemented as siloed interventions despite the potential benefits of integrated approaches. A better understanding of the interactions between these factors is important to strengthen the delivery of integrated services.

Objective: This study investigates the relationship between under-five SAM and malaria infections at the block level in Rajasthan to inform targeted, integrated interventions. By running regression analysis, we will identify associations between these co-occurring health threats to guide state-level policy integration. To the best …

Development And Optimization Of A Novel Eeev Microsphere Immunoassay: Using Xeno-Surveillance Methodology To Characterize Avian Herd Immunity, Kaitlyn Gabriele Maurais

Public Health Theses

Introduction: Eastern equine encephalitis virus (EEEV), a mosquito-borne alphavirus, is detected throughout the eastern United States. The primary enzootic vector, Culiseta melanura (Blacktailed mosquito), allows transmission among 50+ avian host species resulting in complex disease patterns. Spillover to dead-end host mammals, such as equines and humans, rarely occurs, however, human cases can cause severe neurological deficits and have a 30% mortality rate. Eco-epidemiology and avian host immunity patterns are not well characterized for EEEV and require ongoing surveillance to develop more targeted interventions. Methods: Xeno-surveillance is an approach to survey EEEV through hematophagous arthropods, instead of collecting samples from a …

Diagnostic Stewardship: Changing Behavior One Urine Culture At A Time, Beth Warne

Public Health Theses

Urinalysis and urine cultures are important diagnostic tools for diagnosing urinary tract infections. Often urine cultures are ordered without appropriate clinical indications of infection attributable to the urinary tract. Inappropriate urine culture ordering can have significant downstream effects and contribute to the unnecessary use of antibiotics, increased prevalence of Clostridioides difficile infections and antibiotic resistance, as well as wasted resources. A quality improvement project was undertaken at the Veterans Affairs Connecticut Healthcare System (VACHS) to decrease the ordering of inappropriate urine cultures. A new, optional electronic medical record urine culture ordering note requiring documented indication for the test was implemented …

Leveraging Google Trends To Nowcast Covid-19 Epidemics: A Proposed Methodology, Kush Raj Shanker

Public Health Theses

The outbreak of the SARS-CoV-2 pandemic in 2019 has emphasized the need for accurate and timely estimation of infectious disease cases. An important aspect of controlling infectious diseases is the development of robust nowcasting methods, which involve estimating the current and near-future state of an epidemic using real-time data. Google Trends (GT) has emerged as a valuable tool in epidemiology, allowing researchers to track and predict disease outbreaks by analyzing patterns in internet users' searches. While GT provides real-time information on search queries related to infectious disease symptoms and treatment, it has limitations such as data reliability, privacy concerns, sampling …

Ivermectin Mda For Malaria Control And Plasmodium Species Diversity In Burkina Faso, Julia Ellman

Public Health Theses

Malaria is a major cause of mortality globally, but particularly in Africa and among children. As the growth of drug resistance threatens current malaria control and treatment strategies, novel interventions are needed to combat the recent increase in cases. Ivermectin is an endectocide that has been historically used to treat neglected tropical parasitic diseases through mass drug administration (MDA). Recently, it has been demonstrated to have a lethal effect on mosquitos, suggesting its potential as a valuable vector control strategy. RIMDAMAL II is a cluster randomized control trial that was conducted in southwestern Burkina Faso in 2019-2020 to evaluate the …

County-Level Factors Associated With School-Required Immunization Rates Among Connecticut Kindergarteners: 2018-2023, Carolyn Savananh Henry

Public Health Theses

The COVID-19 pandemic brought public attention to the implications of anti-vaccine sentiment to population health. However, the anti-vaccine movement began impacting school-aged children long before the pandemic. This study examines the role of socioeconomic factors in Connecticut kindergarten immunization rates between the 2018-2018 and 2022-2023 school years. Connecticut is the third smallest state in the United States, yet significantly diverse socioeconomic statuses exist within its small spatial boundary.

Analyzing data from the Connecticut Annual School Immunization Survey and the United States Census, we demonstrate a connection between socioeconomic factors and kindergarteners fully up-to-date on all required school immunizations at the …

Hemin As A Contributor To Inflammation In Sickle Cell Disease, Sarah Hinderstein

Public Health Theses

Background: Sickle Cell Disease (SCD) is the most common genetic hematological disorder and puts individuals at increased risk of morbidity and mortality due to infectious disease. Those with SCD also have a reduced capacity to mount successful vaccine responses compared to healthy individuals but there is an incomplete understanding of the mechanisms behind this.

Objectives: We aim to investigate the role of hemin as a potential contributor to inflammatory dysregulation and decreased vaccine immunogenicity in patients with SCD.

Methods: Peripheral blood mononuclear cells (PBMC) were isolated from patients with SCD aged 7-22 and healthy participants aged 22-30. We utilized flow …

Chad's Infectious Disease Surveillance In Context: An Analysis Of 2014-2023 Case Report Data, Sophie Licostie

Public Health Theses

Background: Infectious diseases remain a leading cause of mortality and morbidity in Chad. We aimed to assess trends in the most recent ten years of surveillance data collected by the Ministry of Public Health in Chad to characterize the country’s current disease burden.

Methods: In this analysis of Chadian surveillance data, we analyzed reports of suspected cases across seven diseases from 2014-2023. Data included weekly aggregated case counts by district. We used the data to describe temporal and spatial trends, particularly from 2014-2019 compared to 2020-2023.

Findings: Measles case counts showed seasonal peaks of varying intensity throughout most of 2014-2023. …

Community Health Workers To Strengthen Hiv Care Continuum And Prep Delivery In The Us/Hics: A Scoping Review, Vanessa Abigail Nunez

Public Health Theses

Introduction: With the ongoing global HIV/AIDS burden, community-based service delivery models are increasingly recognized, with community health workers (CHWs) at the forefront. In high-income countries (HICs) like the United States, CHWs have long served marginalized communities, gaining recent legislative attention. Despite this, there's still a need for comprehensive evidence on CHW integration in healthcare delivery.

Methodology: We conducted a scoping review to gather available evidence on community health workers (CHWs) and their impact on HIV outcomes in HICs, and to identify evidence gaps in the use of community-based HIV/PrEP services in HICs. Using the American Public Health Association’s definition of …

Unveiling Chagas Disease: An In-Depth Analysis Of Epidemiological Patterns In High Burden Latin American Nations, Nicole Del Castillo

Public Health Theses

Background: Chagas Disease, endemic to 21 countries in Latin America, is transmitted by triatominae insects infected with parasites known as Trypanosoma cruzi.1–3 It is the most prevalent tropical disease in Latin America, affecting about 6 million individuals across the Americas.1 This literature review aims to summarize unique epidemiological patterns over a 9-year time period from 2010 to 2019 across three nations in South America that experienced the highest Chagas Disease burden in 2019: Bolivia, Venezuela, and Argentina.4

Methods: For this rapid literature review, one independent reviewer extracted all data for publications reviewed within a 9-year time period: 2010 to 2019. …

The Roads Less Traveled: A Metaresearch Analysis Of Local Histories In Racial Health Equity Research, Devin Trévion Brown

Public Health Theses

While it is important that racial health equity research receive growing attention in theUnited States, doing so must involve a thorough recognition and interrogation of the role that structural racism plays in creating different outcomes for Black communities. History aids in making clear the process through which race can become biology as structural racism is embodied by members of Black communities. Guided by Táíwò’s conceptualization of “resource distribution and accumulation” as well as Carter’s discussion of “racialized local biologies”, this cross-sectional meta-research analysis sought to investigate when and how racial health equity research after 2020 utilized local history to understand …

Examining Factors Associated With Covid-19 Disruptions To Tuberculosis Services, Tejaswini Dharmapuri Vachaspathi

Public Health Theses

Background: The COVID-19 pandemic posed unprecedented challenges to global health systems, significantly impacting the delivery of essential health services, including tuberculosis (TB) care. It is important to analyze the factors associated with the reductions in TB notifications during the pandemic, with a focus on high TB burden countries, to inform strategies for making TB programs more resilient to health system shocks.

Methods: Amongst 98 selected high-burden countries, a GLM analysis was employed to examine the association between ‘missed’ TB case notifications from 2020 to 2021, and various country-level factors including: COVID-19 mortality estimates, lockdown stringency index, GDP per capita, health …

Evaluation Of One Health Education Materials: A Scoping Review And Quality Assessment, Sydney Jones

Public Health Theses

The increasing risk of zoonotic spillover, driven by climate change and evolving human behaviors, requires a systematic shift in pandemic prevention strategies towards a One Health approach. Central to this approach is effective health communication intended to translate knowledge into actionable recommendations for the most vulnerable populations. This thesis aims to systematically evaluate the quantity and quality of existing One Health communication materials through a scoping review and two distinct methods of quality evaluation: the CDC Clear Communication Index and content analysis. Among 82 communication materials identified in the scoping review, the median overall CDC Clear Communication Index score was …