The major soil-transmitted helminths (STHs), Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm) and Necator americanus/Ancylostoma duodenal (hookworms) are amongst the most prevalent parasites worldwide. An estimated 4.5 billion individuals are at risk for STH and more than one billion individuals are thought to be infected, of which 450 million have significant morbidity attributable from their infection, school-aged children in particular. In this population infections cause stunting of the linear growth, anemia, reduce the cognitive function and contribute to the existing malnutrition. In Jimma (Ethiopia), STH are highly prevalent, affecting more than 60% of the children (data not published).

Current efforts to control STH infections involve periodic mass drug anthelmintic treatment of infected children in endemic areas and are likely to intensify as more attention is addressed to the importance of these neglected diseases. Monitoring drug efficacy in these control programs has become indispensable in order to detect the emergence of resistance and/or identify confounding factors affecting the drug efficacy. Recently a study has evaluated a single dose albendazole (ALB) in school age children across 7 countries, including Ethiopia, revealing that this regime is highly efficacious for the treatment of A. lumbricoides (99.5%) and hookworms (94.8%), but not for T. trichiura (50.8%). For this parasite a repeated dose regime of ALB on consecutive days is likely to be more appropriate. Alternative drugs are mebendazole (single dose 500mg) and pyrantel+oxantel (single dose 10mg/kg), of which the latter holds promise as it can also be administrated to children between 6 months and 2 years. The main objective of the present study, therefore, is to assess the efficacy of 5 different treatment regimes against T. trichiura in schoolchildren in Jimma, Ethiopia, including albendazole (1 x 400mg, 2 x 400mg), mebendazole (1 x 500mg, 2x 500mg) and pyrantel-oxantel (10mg/kg)+mebendazole (500mg).

Inclusion Criteria:

• all school age children who are eligible to participate in the study

Exclusion Criteria:

• Not willing to participate (no informed consent)
• Unable to give samples for follow up
• Severe intercurrent medical condition
• Diarrhea at first sampling
• Study subjects who had treatment for STH in the last 3 months