Abstract

Schistosomiasis is a tropical disease caused by blood-dwelling fluke of the genus Schistosoma. The main schistosomes infecting human beings are: Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum. Schistosoma intercalatum and Schistosoma mekongi are only of local importance. Two clinical forms of human schistosomiasis occur in Ethiopia: S. mansoni which is transmitted by Biomphalaria pfeifferi and Biomphalaria sudanica;and S. haematobium which is transmitted by Bulinus abyssinica and Bulinus africanus. The national policy on schistosomiasis control has adopted praziquantel as the main drug of use to reduce morbidity. It is widely preferred owing to its safety, present low cost, accepted single dose with improved patient compliance, and efficacy against all five schistosome species. While global use of praziquantel is scaling up, there is also a growing concern regarding low cure rate and drug resistance. Data regarding the efficacy of praziquantel are still missing at this time when there is increased concern that schistosomes might develop resistance to the drug. Results from infected patients, not cured by multiple doses of praziquantel, have been reported from different geographic locations, suggesting that resistance to the drug may be present. In Ethiopia, field report shows that praziquantel is efficacious. The purpose of this review is to summarize results from field and laboratory studies on efficacy of praziquantel mainly in Africa and to relate the findings to the Ethiopian situation.

Key words: Praziquantel, schistosomiasis, drug efficacy, drug resistance, toxicity, dose and drug administration.

Abbreviation

Abbreviations: PZQ, Praziquantel; STH, soil-transmitted helminthes.