Impact of mass chemotherapy filariasis control programme on soil-transmitted helminth infections in Ragama

Abstract

OBJECTIVE: To assess the impact of using albendazole in the'national Mass Drug Administration (MDA) programme for filariasis control, on soil-transmitted helminth (STH) infections'in Ragama. METHODS: The prevalence and intensity of STH infections was assessed before and after introduction of albendazole into the MDA programme in the Ragama MOH area, which has endemic transmission of both lymphatic filariasis and STH. Children attending Year 3 classes in 6 schools (selected in a random stratified manner) were examined during a baseline survey in March-May 2002. The follow-up survey (Sept-Oct) covered Year 4 children in the same schools after the MDA programme in July. All stool samples were examined on the day of collection using the modified Kato-Katz technique. RESULTS: The cumulative prevalence of STH infection was very low in both surveys: 4.5% (12/265) at baseline, and 2.0% (5/252) at follow-up. Trichuriasis was. the commonest infection (4.1% and 1.6%), followed by ascariasis (0.8% and 0.4%). The species prevalence rates, cumulative prevalence, and mean egg counts all declined from baseline to follow-up, but the differences were not statistically significant. The majority of children (85%) examined in the follow-up survey said they had taken both diethylcarbamazine citrate and albendazole during the MDA programme. CONCLUSIONS: Although it is possible that inclusion of albendazole in the MDA programme had an impact on STH infections, it is unlikely that any resultant decline in prevalence will have a significant impact on the health of schoolchildren in the Ragama MOH area since prevalence rates are now very low.