A novel and effective hyperthermia method for Schistosomiasis japonica prevention and treatment1

The emerging resistance to schistosoma has been paid much attention and is in urgent need for a novel strategy to control the prevalent parasitic zoonosis. In this study, the efficiency of hyperthermia therapy was investigated by the skin hyperthermia device. The survival rate of cercariae decreased from 68.15 % (37 °C, 5 min) to 0 (49 °C, 10 min) with the thermal dosages increased, which proved the preventing effect of hyperthermia therapy (P < 0.05). Therapeutic effects were assessed in Schistosoma japonicum-infected BALB/c mice. When the cercarial contact region of the skin was treated at 45-49 °C for 5 min within 8 h of infection, worm reduction rate (WRR) reached 74 %-83 % (P < 0.01). The sensitivity of adult schistosoma to heat was also investigated using microwave intraperitoneal hyperthermia (thermal dosages 42-43 °C, 20 min). The WRR, hepatic shift rates and egg reduction rates were 23.7 %, 40 % and 30 %, respectively, comparing with 80.2 %, 59.6 % and 53.9 % of praziquantel (PZQ)-treated group. Encouraging results have been obtained that hyperthermia can effectively kill schistosomula, especially with the appearance of cercarial dermatitis, while PZQ lacks efficacy against the cercariae. Thus, hyperthermia therapy would show significant benefit in preventing and treatment of schistosoma, especially in the early stage.