Shifting Endemicity of Schistosomiasis in Rural Yemen: Cross-Sectional Insights from Previously Hypoendemic Regions

Abstract

Background: Schistosomiasis is a persistent health concern in Yemen, despite the continued mass drug administration campaigns using praziquantel. This survey investigated the epidemiology of schistosomiasis among schoolchildren in previously identified hypoendemic areas, more than ten years after the last national mapping in 2014 was conducted.

Methods: In June to August 2025, we conducted a cross-sectional survey of 348 children aged 5–15 years living in Jabal Ash Sharq, Hubaysh, and Amd districts. Simultaneously, the data on sociodemographic and behavioral characteristics were obtained through a standardized questionnaire. Urine filtration and the Kato-Katz technique were used to diagnose Schistosoma haematobium and S. mansoni, respectively. Statistical analyses, including binary logistic regression, were used to estimate the independent risk factors for schistosomiasis.

The combined prevalence of schistosomiasis was 19.3% (95% CI: 15, 23%), with S. haematobium (12 · 4 %) being more prevalent than S. mansoni (6.9%). All looked-at districts experienced a substantial increase in the infection rate compared to the 2014 baseline. The majority of infections were of light intensity; however, 16.3% and 20.8% of S. haematobium and S. mansoni cases were classified as moderate to heavy, respectively. Multivariable logistic regression analysis identified age ≥ 10 years (AOR = 2.3; CI: 1.17–4.55; P = 0.016) and higher frequency of contact with open water bodies (AOR = 2.2; 95% CI: 1.22–3.90; P = 0.009) as independent risk factors for schistosomiasis. Any clinical manifestation related to S. haematobium infection, including dysuria, gross hematuria, and dipstick hematuria with proteinuria, was significant.

Conclusion: Schistosomiasis has become meso-endemic in previously hypoendemic areas, with S. haematobium infection accounting for most cases among school children. A significant proportion of cases were mild, but a subset of moderate to heavy infections indicated ongoing transmission. This survey highlights the need to administer praziquantel twice a year to all school-aged children (SAC), along with other control measures, such as health education, improved sanitation, safe water supplies, and snail control.