Soil-transmitted helminthiasis prevalence and infection intensity among school-going children in Timor-Leste after the prolonged interruption of deworming: a cross-sectional survey (2025)
Abstract
Summary Background Timor-Leste reduced soil-transmitted helminth (STH) prevalence from 29% to 18% by 2020 through mass drug administration (MDA) in 2015–2019. School-based deworming was interrupted for nearly four years during the COVID-19 pandemic and resumed in 2022 in 3 municipalities and nationwide in 2024. We aimed to estimate STH prevalence, geographical distribution and associated factors following the re-introduction of MDA. Methods We conducted a cross-sectional, school-based survey from 26 February to 1 May 2025 across all 14 municipalities of Timor-Leste, sampling two schools per municipality and targeting 50 children between 6 and 14 years of age per school. We employed the Kato-Katz technique for stool sample analysis which is the WHO-recommended method for STH surveillance. Associations between STH infection and risk factors were assessed using univariate and multivariable logistic regression. Findings Out of 1960 children, 1236 (63·1%) provided analysable samples (615 [49·8%] girls, 621 [50·2%] boys); median age of the children was 8·7 years (IQR 8–10, range 6–14); ethnicity data was not available. Weighted national STH prevalence was 29·3% (95% CI 24·3–34·2), close to the 2012 baseline (29%) and above the 2020 figure (18%). Prevalence ranged from 2·2% (Oe-Cusse) to 91·5% (Manatuto). Ascaris lumbricoides accounted for 95·8% of infections; moderate-to-heavy infections affected 15·7% of children. Interpretation National STH prevalence has returned to near pre-control levels after the pandemic-related interruption of school-based deworming. Restoring and strengthening school-based deworming, with twice-yearly MDA where prevalence is at least 50%, along with WASH measures and community engagement is needed to regain control. Funding This study was funded by the 10.13039/501100003605Korea International Cooperation Agency (KOICA) and the United Nations Department of Economic and Social Affairs (UNDESA).