Parasitic worms that infect the intestines and spread via contaminated soil affect one third of the world’s population. Known as soil-transmitted helminths (STHs), these parasites can contribute to stunted growth and development in children. A new PLOS Neglected Tropical Diseases study examines efforts to prevent the spread of STHs, finding that community-based control programs may reach a higher number of children than school-based programs.
Naomi Clarke and Susana Vaz Nery of the Australian National University, along with their colleagues enrolled, six Timor-Leste communities in this pilot study. Three communities received a School-based Deworming and Water, Sanitation, and Hygiene (“(S)WASH-D”) program, a program that included the kids practicing daily handwashing and toothbrushing as group activities, along with biannual deworming with medication. Three other communities received a community-based deworming and WASH program, a program that includes access to an improved water supply, house-by-house education on hygiene practices, and mass-drug distribution of deworming medication. An important goal of both the WASH programs tested is to eliminate the practice of open defecation among school-aged children, which promotes STH spread.
Before and after the six-month study, the researchers measured rates of STH infection among school-age children and their practice of open defecation. While the (S)WASH-D program did improve school sanitation, handwashing facilities, and hygiene behavior, open defecation rates dropped by only 8.4 percent. The community WASH program not only improved sanitation in households, but also reduced open defecation rates by 26.9 percent. The odds of STH infection were 58 percent lower among children enrolled in the community program than among those in the (S)WASH-D program.
This was one pilot study, and the researchers note that “a fully-powered trial should be implemented such that the WASH intervention is conducted close to the beginning of the school year and it is crucial to ensure that partner WASH agencies have capacity to complete their interventions in a timely and simultaneous manner. Successful study implementation will require co-operation and regular liaison between the research team, WASH agencies, school and community leaders, and the Ministry of Education.”
Next steps for this study include a large-scale trial Dr. Vaz Nery is planning in the Philippines to further investigate this study’s findings.
Reference: Clarke NE, Clements ACA, Amaral S, Richardson A, McCarthy JS, et al. (2018) (S)WASH-D for Worms: A pilot study investigating the differential impact of school- versus community-based integrated control programs for soil-transmitted helminths. PLOS Neglected Tropical Diseases 12(5): e0006389. https://doi.org/10.1371/journal.pntd.0006389
Image credit: Clarke and Vaz Nery et al, (2018)