Comparison of the efficacy of mebendazole, albendazole and pyrantel in treatment of human hookworm infections in the Southern Region of Mali, West Africa

A randomized, placebo-controlled trial of the efficacy of pyrantel (single dose 125 mg/kg bodyweight), mebendazole (single 500 mg dose) and albendazol e (single;100 mg dose) in the treatment of hookworm infections (Necator ame ricanus,) was carried our in January 1998 in the Southern Region of Mall, W est Africa, during the period of Ramadan (Islamic fast). Statistical analys is of the pre-intervention faecal egg counts showed that there was a signif icant pre-treatment chance bias, despite randomization of subjects into tre atment groups, arising from the main effect of sex (heavier infections amon g males) and a sex X treatment interaction (the sex bias was not evident in the pyrantel-treatment group). The participants were reexamined 10 days af ter treatment, and after controlling for the drift in faecal egg counts in the placebo-treated subset, age, sex, fasting and intensity of infection, a lbendazole was clearly the most effective drug showing consistently efficac ies in the range 92.1 to 99.7%, depending on the method of evaluation and t he particular subset of the treatment group. Neither mebendazole nor pyrant el was as effective, with efficacies ranging from 60.9 to 89.8% and 4.8 to 89.7%, respectively. Fasting made no difference to drug efficacy. On the ba sis of our results the single 400 mg dose of albendazole is the treatment o f choice for hookworm infections in this region of Mali. We emphasize the n eed for standardization of the methods used for trial designs, for calculat ion of summary data relating to drug efficacies and the accompanying statis tical tests.