The sensitivity of artesunate against Schistosoma japonicum decreased after 10 years of use in China.

Schistosomiasis due to Schistosoma japonicum is a major public health problem in China. Since 1995, artesunate has been used to treat and prevent schistosome infections in China. Artesunate previously showed a high prophylactic efficacy against schistosome infection, with a protection rate of 100%. However, recent clinical trials and animal experiments have found that the sensitivity of many schistosomes to artesunate, including Schistosoma mekongi and Schistosoma mansoni, decreased. Whether the prophylactic efficacy of artesunate on Schistosomiasis japonica decreased after being used over 10-year period was still unknown. In the current study, we conducted a double-blind trial and found that the protection rate of artesunate was only 13.5% in the Administration I group, whose dosage schedule was identical to schedules used in previous studies. Therefore, the sensitivity of S. japonicum to artesunate was confirmed to have decreased after being using for over 10 years. Moreover, when we increased the concentration of artesunate during the first week and third week, the protection reached 74.8%.