Malnutrition among children under 7 years of age linked to ascariasis: evidence from West Sumba, Indonesia, despite ongoing deworming program

Background: Soil-transmitted helminth (STH) diseases persist in various Asian nations, including Indonesia. The West Sumba District, located in East Nusa Tenggara Province, Indonesia, has been implementing a deworming program targeting children under 7 years of age since 2017. This study aims to assess the prevalence, intensity, and distribution of soil-transmitted helminthiasis and its association with nutritional status among children under 7 years of age in West Sumba District. Methods: In this community-based cross-sectional study, children under 7 years of age registered at integrated health posts in eight primary health facilities in West Sumba District were randomly sampled (443 subjects) from October 2022 to January 2023. Kato-Katz methods were applied to detect STH infections. Malnutrition was determined using a Height-for-Age table with a Z-score (HAZ). Results: The prevalence of STH in children under 7 years of age was 32.5 (144/443). Kota Waikabubak sub-district had the highest STH cases, with Trichuris trichiura (34.0; 49/144)) and Ascaris lumbricoides (27.8; 40/144) being the two common species. The following variables have been significant risk factors for STH infection: children aged > 2 years (OR: 5.9, 95 CI: 3.64-9.55, p < 0.001), parents with basic (OR: 1.8, 95 CI: 1.07-2.73, p < 0.001) and no educational level (OR: 4.1, 95 CI: 2.30-7.03, p < 0.001), family with monthly income < 2.5 million rupiahs (OR: 5.6, 95 CI: 1.70-18.78, p < 0.001), a preference for ground-based play (OR: 5.2, 95 CI: 2.65-10.04, p < 0.001), the presence of a private toilet at home (OR: 3.4, 95 CI: 2.22-5.19, p < 0.001), and have no septic tank for final disposal of stool (OR: 3.3, 95 CI: 1.91-5.75, p < 0.001). Malnutrition, indicated by stunted and severely stunted children with a range of cases from 5 to 37, was strongly linked with A. lumbricoides infection (OR: 3.45, 95 CI: 1.70-7.02, p < 0.001) occurring in Kota Waikabubak and supported by spatial map analysis. Conclusions: Current research indicates a notable link between STH infection, i.e. ascariasis, and stunting as a malnutrition status in children under 7 years of age in Kota Waikabubak, a densely populated capital city in the district's centre. This finding addresses a key public health gap by providing evidence on the early burden of helminthiasis in low-resource tropical settings. © The Author(s) 2025.