[Role of several hosts in transmission of Schistosomiasis japonica in lake region].

From 1989 to 1990, an investigation was conducted in three villages in Junsan township, Hanyang County, Hubei Province. The results showed that the infection rates of local residents were 55.1%, 49.5% and 44.3%, respectively; the EPG were 5.6, 5.2 and 2.0, respectively; the relative transmission index (RTI) were 7.1%, being highest in the age group 30-39 years. The relative index of potential contamination (IPC) was 67.2% in the age group 20-49 years, this group was considered as the main transmission source in the population. In animal hosts buffaloes, pigs and dogs, the infection rates were 35.7%, 60.0% and 75.0%, respectively; MPG (miracidium per gram), 0.4, 0.4 and 80.4, respectively; RTI (relative transmission index), 38.6%, 7.7 and 46.6%, respectively. The infection rates of pigs and dogs were high in Huangshi village, while the infection rate of buffaloes was high in Chuangjiang village. These results coincided with the transmission of schistosomiasis in these villages. The results showed that dogs as the main transmission sources had important significance in the epidemiology of schistosomiasis and that buffaloes and pigs herd and fed in the snail-habitats could be heavily infected.