[Role of human and domestic animal reservoirs of schistosomiasis japonica in Dongting and Boyang Lake regions].

In Dongting and Boyang Lake regions, the main reservoirs of schistosomiasis were farm cattle (mostly buffaloes), pigs and mobile nonnatives. However, the role of these reservoirs in different types of endemic areas were not the same in the transmission of schistosomiasis. In islet-beach type area, the main infectious sources were pigs and local residents. The proportion of IRC (Index of Real Contamination) of local residents and pigs to the total IRC was 30.9% and 39.9% respectively. In fork-beach type area having luxuriant grass and abundant aquatic products, there were a number of buffaloes and people from other places. The proportion of IRC of the nonnative buffaloes and mobile nonnatives made up 51.9% and 21.8% of the total IRC respectively, the main reservoirs being from other places. The embankment-beach type area had a vast snail-infected area and a large number of buffaloes from both local and other places as well as mobile nonnatives. The proportion of IRC of buffaloes and nonnatives made up 69.8% and 21.4% of the total IRC respectively, serving as the main reservoirs. As regard to season differences, the infected buffaloes were the main reservoirs during dry seasons, especially from March to May, whereas the mobile nonnatives including fishermen and boatmen were the main infectious sources during flood seasons from June to October.