Impact of Health Education on Soil-Transmitted Helminth Infections in Schoolchildren of the Peruvian Amazon: A Cluster-Randomized Controlled Trial

Abstract

To control soil-transmitted helminth (STH) infections, the World Health Organization recommends school-based deworming programs with a health hygiene education component. The effect of such health hygiene interventions, however, has not been adequately studied. The objective of the present study was to determine the effectiveness of a health hygiene education intervention on the occurrence of STH re-infection four months post-de-worming. An open-label pair-matched cluster-randomized trial was conducted in Grade 5 schoolchildren of 18 primary schools (9 intervention and 9 control) in the Peruvian Amazon. Baseline assessment included interview with a pre-tested questionnaire and collection of single stool specimens that were examined using the single Kato-Katz thick smear. All schoolchildren were then treated with single-dose albendazole (400 mg). Schoolchildren in intervention schools then received 1) an initial one hour in-class activity on health hygiene and sanitation and 30-minute refresher activities every two weeks over four months; and 2) a half-day workshop for teachers and principals, while children in control schools did not. Four months later, STH infection was re-assessed in all schools by laboratory technologists blinded to intervention status. From April 21–October 20, 2010, a total of 1,089 schoolchildren (518 and 571 from intervention and control schools, respectively) participated in this study. Intervention children scored significantly higher on all aspects of a test of STH-related knowledge compared with control children (aOR = 18·4; 95% CI: 12·7 to 26·6). The intensity of Ascaris lumbricoides infection at follow-up was statistically significantly lower (by 58%) in children in intervention schools compared with children in control schools (aIRR = 0·42; 95% CI = 0·21 to 0·85). No significant changes in hookworm or Trichuris trichiura intensity were observed. A school-based health hygiene education intervention was effective in increasing STH knowledge and in reducing Ascaris lumbricoides infection. The benefits of school-based periodic deworming programs are likely to be enhanced when a sustained health hygiene education intervention is integrated into school curricula. The World Health Organization (WHO) recommends including a health hygiene education component into school-based deworming programs to reduce intestinal worm re-infection in treated children; however, the effect of these types of educational interventions has not been adequately studied. In this study, we investigated the effect of a health hygiene education intervention within a deworming program targeting Grade 5 schoolchildren in Bélen, Peru, a highly worm-endemic area. Following baseline assessment, all children in 18 primary schools received deworming. Subsequently, nine schools were randomly assigned to receive a health hygiene educational intervention and nine were randomly assigned to not receive the educational intervention. Four months later, children from schools that received the educational intervention were found to be more knowledgeable about the transmission and prevention of intestinal worm infections and, although there was no observed effect on whipworms or hookworms, children were also significantly less likely to be infected with roundworms. These results support the WHO recommendation for the inclusion of health hygiene education into school-based deworming programs. The beneficial effects of deworming are likely to be enhanced when appropriate health hygiene education is integrated into the school curricula.