Abstract: AIM:To study the prophylactic effectof artemether againstinfection caused by
Schistosoma japonicum,in an endemic area of marshlands.METHODS:From April to November, 1996,2 villages in Tangtian township of Guichi City,Anhui Province were selected as the pilot site.A
total of 920 villagers aged 6 - 6 5 years were selected as subjects and allocated randomly to
artemether group and the control group by pairing method.About 2 0 days before artemether
prevention stool examination was carried out for the villagers of both groups, which was followed by treatment of all the examinees with praziquantel at a single do e of 40- 50 mg/kg. In artemether group , an initial do se of 6mg/kg was given in the last ten-day period of May, pursued by repeated dosing once every 15 days for 10 times. Placebo (starch) 6 mg/kg was given to villagers in the control group simultaneously. The preventive efficacy was evaluated by stool examination 4 weeks after the last medication. RESULTS: In artemether group no egg positive case (0/433) was seen, while in the control group 40 villagers were revealed egg-positive with an infection rate of 8. 8% (40/452). Furthermore, 1 case of acute schistosomiasis was present in the control group , but none in artemether group. No apparent changes in hepatic and renal functions, reticulocyte count or electrocardiograph was evidenced after completion of artemether administrartion. CONCLUSION: In hyper-endemic area of schistosomiasis in marsh lands, artemether 6 mg/kg given orally once every 15 days to villagers throughout the whole transmission season resulted in promising protection, that the drug could prevent them from schistosome infection. The study provides an effective measure for planning new strategies to be used in schistosomsis control.

Key words: Schistosomiasis, prophylaxis, artemether