Epidemiology of 6 cases of human infection with influenza A (H7N9) virus in Xiaoshan, Hangzhou

To understand the epidemiological characteristics and infection source of human infection with influenza A (H7N9) virus, epidemiological analysis was conducted for 6 cases of human infection with influenza A (H7N9) virus occurred in Xiaoshan during 1-21 April 2013. The analysis indicated that all the 6 cases had farm produce market exposure histories. The H7N9 viral nucleic acid positive rate was 47.06% in environment samples collected in farm produce markets (16/34).