Results of Influenza and Acute Respiratory Disease Epidemiological Surveillance in 2016-2017 in the Khabarovsk Territory

Abstract

During 2016 and first half of 2017 an activation of circulation of three serotypes of influenza virus followed by increase in influenza incidence was registered in the Khabarovsk territory. During the first quarter of 2016 A/H1N1pdm09/ influenza virus was most prevalent. Simultaneously A/H3N2/ influenza virus was detected. However its abundance was 11,3 times less frequent than A/H1N1pdm09/. Epidemiologic increase of influenza and acute respiratory disease incidence due to circulation of subtype A/H3N2/ was registered during the IV quarter of 2016 and almost ceased in I quarter of 2017. Reciprocal epidemiological tendencies were registered for the influenza virus “B”. The hallmark of all three increases in influenza virus “B” incidence was stated as relatively low incidence during the studied period of time. The last period of influenza virus “B” incidence increase did not exceed the epidemic threshold. Analysis of influenza-like viruses circulation as well as influenza virus and other respiratory viruses role in age-related incidence were conducted on the territory of the region. A comparative analysis of A/H3N2/ and «В»influenza viruses influence on the clinical course of respiratory diseases was conducted.