EVALUATION OF A TWICE-A-WEEK APPLICATION OF 1-PERCENT NICLOSAMIDE LOTION IN PREVENTING SCHISTOSOMA-HAEMATOBIUM REINFECTION

A randomized double-blind trial was conducted to assess the efficacy o f a twice-a-week application of 1% niclosamide lotion for prevention o f Schistosoma haematobium reinfection. Six hundred farmers in Fayoum, Egypt, 18-40 years of age, were treated to cure their S. haematobium i nfection, then randomly assigned to self-apply niclosamide or placebo lotion to their Limbs, neck, and torso. Subjects were exposed to schis tosomal-infested water during routine irrigation activities from April to October 1992. Three hundred fifty subjects met the inclusion crite ria and completed the trial, 169 (48.3%) in the niclosamide group and 181 (51.7%) in the placebo group. The subjects assigned to the niclosa mide-treated group were comparable with those in the placebo group in age (27.2 versus 27.8 years), total water contact (101.9 versus 109.0 hr), lotion application compliance (93.5% versus 90.6%), and avoidance of whole body water contact (94.7% versus 96.7%). The reinfection rat e with S. haematabium was 30.8% in the niclosamide-treated group and 2 8.2% in the placebo group. Niclosamide lotion applied to the limbs and trunk twice a week failed to prevent S. haematobium reinfection.