Geostatistical analysis to guide treatment decisions for soil-transmitted helminthiasis control in Uganda

Background: Soil-transmitted helminth (STH) infections remain a public health problem in Uganda despite biannual national deworming campaigns implemented since the early 2000s. Recent surveys have indicated a heterogeneous STH infection prevalence, suggesting that the current blanket deworming strategy may no longer be cost-effective. This study identified infection predictors, estimated the geographic distribution of STH infection prevalence by species, and calculated deworming needs for school-age children (SAC). Methodology: Bayesian geostatistical models were applied to STH survey data (2021–2023) for each species (i.e., Ascaris lumbricoides, hookworm, and Trichuris trichiura). Climatic, environmental, and socioeconomic predictors were obtained from remote sensing sources, model-based databases, and demographic and health surveys. Prevalence was predicted on a 1 × 1 km2 grid across Uganda, and district-level estimates were used to classify each district into treatment frequency categories and to determine its deworming tablet requirements. Principal findings: The national prevalence of A. lumbricoides, T. trichiura, and hookworm was estimated at 5.0% (95% Bayesian credible interval [BCI]: 0.8–11.8%), 3.5% (0.7–9.3%), and 7.2% (0.55.7–32.911.1%), respectively. The overall prevalence of any STH infection was 14.3% (9.6–21.8%). High intra-district variation in prevalence was observed. Of 146 implementation units (136 districts and 10 cities), 49 require twice-year treatment, 34 once-yearly treatment, 61 every other year treatment, and 2 had a prevalence