Co-Occurrence of Malaria, Pneumonia, and Diarrheal Disease Among Households: A Cohort Study in Rural Western Uganda.

OBJECTIVES: This study aims to identify patterns associated with clustering and co-occurrence of malaria, pneumonia, and diarrhoea, the leading causes of death in children under age five in sub-Saharan Africa, in western Uganda to generate evidence for integrated prevention and control measures. METHODS: We conducted a prospective longitudinal study complemented by passive surveillance at local clinics. All households in the three selected villages were eligible to participate. Household-level socioeconomic and geographic data were linked to clinically diagnosed disease outcomes. Co-occurrence of diseases within households, defined as the diagnoses of two of the three diseases of interest (malaria, pneumonia, and diarrhoea) within a four-week period, was assessed using a Poisson model with a log link. Multinomial logistic regression models were fit to assess the association between patterns of malaria and pneumonia occurrence with socioeconomic and geographic factors. RESULTS: A total of 399 households were enrolled and completed baseline surveys. The smallest village accounted for 68.5%, 43.2%, and 38.1% of malaria, pneumonia, and diarrhoea cases, respectively. After adjusting for village, socioeconomic status, and the mean age of children in the home, households in Kasanzi had a higher relative risk of having both malaria and pneumonia versus neither disease compared to households in Bunyangoni (RRR: 33.84, 95% CI: 7.10, 161.24). For models replacing village with elevation, households in at higher elevations had a higher relative risk of having both malaria and pneumonia versus neither disease compared to households in at lower elevations (RRR: 26.59, 95% CI: 2.53, 279.84). No clear associations were found between malaria and pneumonia co-occurrence and SES. CONCLUSIONS: Findings demonstrate that within small geographic areas, disease burden can vary dramatically across communities. Targeted, community-level interventions, rather than broad regional programs, are essential to address the distinct transmission dynamics and overlapping risks faced by high-burden communities.