Insights into geohelminth contamination in Bangladesh: feasibility of a modified diagnostic method and prevalence study

Abstract

The objectives of this study were to evaluate a modified method for isolating geohelminth eggs and to assess the geohelminth contamination in Bangladesh. The efficacy of the modified method was evaluated using naturally contaminated and experimentally seeded soil samples. In total, 240 samples were assessed from four different sites in three geographic contexts. A questionnaire survey with 50 professionals was conducted. The modified method showed considerable efficacy in isolating parasitic eggs from naturally contaminated soil (54.0%) and experimentally seeded soils (63.0% for Toxocara eggs and 52.0% for Ascaris eggs). The modified method was described as convenient by the majority of participants. Overall prevalence was 52.5%, with several species of helminth observed, including Toxocara sp., Ascaridia galli/Heterakis gallinarum, Ascaris sp., hookworms/strongyles, Capillaria sp., Trichuris sp., and taeniids). The contamination rate was found to be higher around livestock farms (76.7%), followed by latrines (63.3%), households (41.6%), and schools (28.3%). The modified method was shown to be feasible in terms of field applicability and egg recovery rate, and could be adopted in low-resource settings. A substantial prevalence of geohelminths was observed, with some of the species associated with zoonoses. These findings highlight the urgent need for widespread mapping of geohelminths to avoid spillovers to animals and humans.