This review evaluates the effects of mass deworming for soil‐transmitted helminths on growth, educational achievement, cognition, school attendance, quality of life and adverse effects in children in endemic helminth areas.
Mass deworming for soil‐transmitted helminths probably has little to no effect on weight, height, school attendance, cognition measured by short‐term attention, or mortality. There are no data on short‐term quality of life and little evidence of adverse effects.
Mass deworming for schistosomiasis alone may slightly increase weight but probably has little to no effect on height and cognition. The evidence does not support indirect benefits for untreated children from being exposed to treated children. One moderate quality long term study showed an increase in economic productivity (hours worked) and increase in educational enrollment 10 years later of mass deworming and hygiene promotion. But, it is uncertain whether these effects are due to the deworming or the combined hygiene intervention.
Findings are consistent for various groups of the population by age, gender, worm prevalence, baseline nutritional status, compliance, impact on worms, infection intensity, types of worms, risk of bias, and study characteristics. Deworming for children who screened positive for schistosomiasis or soil‐transmitted helminths results in larger gains in weight but no difference in effect on height, cognition or school attendance. Also, one low to moderate quality study showed long‐term benefit on school enrolment of sanitation improvement combined with screening and treating people for hookworm infection.
Abstract
BackgroundSoil‐transmitted helminthiasis and schistosomiasis, considered among the neglected tropical diseases by the World Health Organization (WHO), affect more than a third of the world's population, with varying intensity of infection. There is debate about the effectiveness and cost‐effectiveness of mass deworming of children as a strategy to improve child health in endemic areas.
ObjectivesThe objective of this review was to evaluate the effects of mass deworming for soil‐transmitted helminths with or without deworming for schistosomiasis or co‐interventions on growth, educational achievement, cognition, school attendance, quality of life and adverse effects in children inendemic helminth areas.We also aimed to assess possible effect modifiers using pre‐planned subgroup analysis of age, sex, prevalence of worms and baseline nutritional status.
Search strategyOur librarian scientist designed a search strategy that was reviewed by the Campbell Collaboration librarian for the following 11 electronic databases: MEDLINE, CINAHL, LILACS, EMBASE, the Cochrane Library, Econlit, Internet Documents in Economics Access Service (IDEAS), Public Affairs Information Service (PAIS), Social Services Abstracts, Global Health CABI and CAB Abstracts, up to May 13, 2015. We also searched websites and clinical trial registers, other systematic reviews, and contacted authors and experts in the field.
Study selection ...