Epidemiological characteristics of 19 cases of human infection with avian influenza A(H7N9)virus in Shenzhen city

Objective To analyze epidemiological characteristics of human infection of avian influenza A(H7N9)and to provide scientific evidences for prevention and control of the epidemic.Methods Epidemiological analysis was conducted based on the data of 19 laboratory confirmed cases of human infection with H7N9 virus in Shenzhen city.Results Totally 19 cases were confirmed during December 19,2013-February 15,2014,with 17 cured and 2 dead.Of all the cases,10 were male and 9 were female;the median age of the cases was 56 years and the youngest and oldest was 6 and 81 years,and 68.4%of the cases were aged 40 years or older;the majority of the cases were retirees(31.6%),housekeeping workers(26.3%),and white- and blue-collar workers(21.1%);73.7%of the cases were reported in Longgang and Luohu district and epidemiological survey on the cases indicated that 11 cases had the history of exposure to alive poultry market.Medical supervision was conducted for 830 close contacts of the cases,including 587 medical staff.No secondary cases were found.Conclusion Elder people are the susceptible population of human infection of avian influenza A(H7N9).Standard management for alive poultry markets is important to prevent H7N9 virus epidemic in urban population.