Efficacy of a single dose of mebendazole on prevalence and intensity of soil-transmitted nematodes in Zanzibar.

The efficacy of a single-dose of mebendazole to treat intestinal helminths was studied in Pemba Island, Zanzibar, with the view of incorporating it in future control programmes. A single Kato-Katz stool examination was performed on 2,269 individuals from all age groups. 1,883 individuals were treated with 500 mg of mebendazole (250 mg for children below two years) and re-examined one month and four months after therapy. A total of 466 presented themselves for all three surveys and the data has been reported in this study. The overall cure rate for ascariasis was 93.2% and reduction of egg load after treatment was 89.8% in persistent positive cases. Although the cure rates were lower in trichuriasis (25.6%) and hookworm (17.8%) infections, egg reduction was more evident with 47% for Trichuris trichiura and 51.9% for hookworms. A single dose of mebendazole results not only in a high cure rate for ascariasis but also in a decrease in intensity of ascariasis, trichuriasis and hookworm infections, thereby contributing to its incorporation into low-budget control programmes in developing countries.