Abstract: Black fever was a major infectious disease in Huaihe River basin during the republic of China.The disease occurred almost every year, and the number of people with the disease had increased year by year since the great flood in 1931. Affected by economic conditions and ecological environment, most of the patients were scattered in the countryside, and relatively rare in the cities are .Overall, among the patients, there were more male than female, with more children and adolescents under 30.