Epidemiological characteristics of 8 cases of human infection with avian influenza A (H7N9) virus n Shangcheng district, Hangzhou

Objective To further understand the epidemiological characteristics of human infection with avian influenza A (H7N9) virus and provide evidence for the future prevention and control of the infection. Methods Epidemiological analysis was conducted on 8 laboratory confirmed cases of human infection with H7N9 virus in Shangcheng district, Hangzhou. Results The 8 cases occurred during 20 March-16 April 2013. Seven cases were males. The median of patients' age was 70.5 years. The average interval between onset and medical care seeking was 2.5 days. Epidemiological survey indicated that all the 8 cases had histories of exposure to alive poultry markets. Medical supervision was conducted for 167 close contacts, including 133 medical staff. No secondary cases were found. Conclusion Old men in urban area were at high-risk to be infected with H7N9 virus. No evidence showed that the human to human transmission of the infection had occurred. Early detection, early reporting, early diagnosis and early treatment are key steps for the effective prevention and control, increasing cure rate and decreasing case fatality of the human infection. Standard management of alive poultry markets is important to prevent H7N9 virus infection in urban population and improving the triage of infectious cases and medical staff's self protection in hospitals are essential in the prevention and control of H7N9 virus infection.