Anthelmintics and mass therapy
Kotcher, E.; Chavarria, A.P.
Health Laboratory Science 12(2): 112-115
1975
ISSN/ISBN: 0017-9035 PMID: 1052506 Document Number: 92752
A study designed to evaluate the efficacy of mass anthelmintic therapy was carried out on 2 ecologically similar Costa Rican communities. Thiabendazole was administered twice within 1 6 wk period in the experimental community at 75 mg/kg body weight. Piperazine hexahydrate was given once to the control community. At the beginning of the study the prevalence rates for Strongyloides stercoralis, the hookworm, Trichuris trichiura and Ascaris lumbricoides were comparable in both communities. In the thiabendazole-treated community, there was drop in the prevalence of S. stercoralis from 19.2% to 0.3%, whereas the drug had little effect on the prevalences of the hookworms, whipworm and Ascaris. Post-treatment stool examinations at 1, 2 and 7 yr showed prevalence rates remained very low for Strongyloides, but high for the whipworm and Ascaris. For the hookworms, the prevalence rate dropped in the last 5-yr period from 70.7% to 20.4%. In the piperazine-treated community, both Strongyloides and hookworm prevalences dropped from 17.9% to 5.8% and 46.8% to 12.2%, respectively, in the 7 yr period. Trichuris and Ascaris prevalence rates remained essentially the same. Thiabendazole mass treatment can reduce Strongyloides prevalence very markedly and possibly break the transmission cycle. Because prevalence rates for hookworm also dropped in both communities, the role of increased wearing of shoes, boots, etc., be discounted.