Objective  To analyze epidemiological characteristics of first diagnosed case of human avian influenza A (H7N9) virus infection for providing evidences to prevention and control of the epidemic.

  Methods  We conducted an epidemiological survey on the incidence and diagnosis, probable infection source, transmission route, and relevant exposures for the first avian influenza A (H7N9) virus infection in Liaoning province. Meanwhile, medical observations were carried out among those with close contact with the diagnosed case; external environmental surveillance and epidemic focus disinfection were also implemented.

  Results  A 67 years old male urban resident was admitted into a hospital in Shenyang city of Liaoning province on June 8, 2016 for the treatment of fever, cough and phlegm. The patient’s history of exposure to dead chicken was confirmed later. Throat swab and sputum from lower respiratory tract specimens of the patient were positive for avian influenza A (H7N9) viral nucleic acid based on the results of real-time PCR test performed by laboratories at municipal, provincial, and national level. The patient died 17 days after the onset of the disease. No abnormal symptoms were observed and no avian influenza A (H7N9) viral nucleic acid positive specimens were detected during the 7-day medical observation among the 119 close contacts of the patient.

  Conclusion  The prevention and control of H7N9 avian influenza epidemic in Liaoning province should be concerned seriously. Management on free-range poultry and live poultry markets in urban areas needs to be strengthened for the prevention of probable environment contamination of avian influenza A (H7N9) virus.