Evaluation of Environmental and Immunization Interventions in Shaping Respiratory Health in Low and Middle-Income Countries

From development through adulthood, respiratory health is shaped by a complex interplay of socioeconomic, biological, environmental, and cultural factors across the life course. While numerous interventions target these domains to improve respiratory outcomes, it is essential to rigorously assess their effectiveness and determine how they can be integrated into broader public health strategies. This dissertation focuses on the roles of environmental and immunization interventions in shaping respiratory health among populations in low- and middle-income countries (LMICs). The first two papers draw on data from the Nepal Cookstove Intervention Project, a pair of randomized trials conducted in rural Nepal between 2010 and 2014. These trials aimed to evaluate the impact of clean cooking interventions on air quality, reproductive outcomes, and respiratory morbidity among young children. In the first paper, we examined whether clean cooking reduces respiratory infections and whether different stove technologies differ in their effectiveness. Although cleaner cookstoves substantially reduced air pollution compared to traditional stoves, their impact on respiratory infections was modest, with no meaningful differences observed between stove types. Notably, greater benefits were observed among households with smokers and those that installed stoves during winter. These findings suggest that while clean cooking has measurable benefits, maximizing its impact requires addressing additional pollution sources and improving sustained use and compliance. In the second paper, we evaluated the effect of clean cooking on pulmonary function. We found that clean cooking was associated with improved lung function, including a significant reduction in the risk of pulmonary obstruction. The magnitude of benefit varied by household context, with stronger effects observed in households with smokers and those using outdoor installations. These results highlight that ventilation and continued exposure to pollutants remain critical factors influencing intervention effectiveness. The third paper utilized Demographic and Health Surveys and Multiple Indicator Cluster Surveys to assess the broader population-level impact of pneumococcal conjugate vaccine (PCV) on acute respiratory infection (ARI), antibiotic use during ARI episodes, and under-five mortality. We found that both PCV introduction and increasing coverage were associated with reductions in ARI prevalence. However, no significant reductions were observed in antibiotic use or under-five mortality. These findings suggest that while PCV plays an important role in reducing respiratory disease burden, maximizing its impact requires complementary strategies, including improved antibiotic stewardship and adherence to clinical guidelines. Overall, this dissertation demonstrates that while environmental and immunization interventions can yield meaningful improvements in respiratory health, their effectiveness is influenced by contextual and behavioral factors that are difficult to control in real-world settings. These findings underscore the importance of considering implementation context, strengthening intervention adherence, and integrating other community-based strategies. Future research should evaluate these interventions across diverse populations, longer time horizons, and varied methodological approaches to generate more consistent and generalizable evidence. At the same time, the results presented here provide important insights to inform policy and guide the design of more effective public health interventions.

Author

• Kim, Yeon Heev

Language

• en

Date created

• 2026

Type of Work

• Dissertation

License

• All rights reserved

Rights statement

• In Copyright

GW Unit

• Global Health

Degree

• Ph.D.

Advisor

• Smith, Emily R.

Committee Member(s)

• Tielsch, James M.
• Katz, Joanne

Persistent URL

•  https://scholarspace.library.gwu.edu/etd/dn39x242v