Are there vampires in Yangzhou?

Schistosomiasis is a Class B infectious disease, mainly spread by Oncomelania hupensis, which is easy to appear in the middle and lower reaches of the Yangtze River, lakes and mountainous areas. The main symptom is rash, followed by fever, diarrhea and occasional cough. In severe cases, hepatosplenomegaly and functional failure will occur, and people will become emaciated and even lose their labor force. The results of human blood tests showed that the eosinophil index increased.

At present, seven provinces in China are endemic areas of schistosomiasis, including Anhui, Jiangsu, Jiangxi, Sichuan, Hunan, Hubei and Yunnan. There are about 800,000 schistosomiasis patients in China, including 1000 to 2,000 acute cases every year.

Xu Weimin said that Oncomelania hupensis, the host of schistosomiasis, generally lives in grass beaches, ponds, ditches and other fields and places with water. If people come into contact with water in unknown waters in the wild, the larvae and cercariae of Schistosoma japonicum can easily enter the human body and cause infection. At the same time, there will be miracidium in the feces of infected people. If it is excreted in the wild at will, the miracidium will enter the snail through water, causing a vicious circle of large-scale diffusion.

He introduced that with the acceleration of urbanization, snails that used to grow easily in rural areas have now increased in the suburbs, showing a trend of spreading to cities and towns.