Abstract: Objective To analyze the epidemiological characteristics and research progress of human infection with avian influenza A (H7N9) virus and the present problems during control and prevention,and to offer a proposal for future control and prevention.Methods Face-to-face interviews were used to collect the epidemiology data and the control measures related information.Then the epidemiological characteristics and the effect of control measures were analyzed.Results Among 44 persons confirmed with H7N9 virus infection,including 6 deaths,61.36% were male;the median age of the patients was 60.18 years (range,32 to 86),with 79.55% older than 50 years,68.18% were country dweller or retirees,and 90.91% were from Hangzhou and Huzhou city.Of 37 cases with available data on disease history,78.38% had chronic disease such as hypertension,diabetes or heart disease;of 38 cases with available data on exposure history,78.95% had an exposure to live poultry.All 1004 close contacts of the patients were negative for not infected.It seemed that suspension of live poultry trade could terminate the transmission.Conclusion The epidemiological characteristics of human infection with avian influenza A (H7N9) virus is not yet understood completely.Organizing and coordinating relevant departments to carry out collaborative surveillance research,control and prevention are a pressing matter of the moment.