Differences Depending on the Etiology of Influenza Epidemics in 2014-2017

Abstract

The goal is to identify features of epidemic process of influenza depending on the etiology of epidemics to clarification of the forecast for future epidemics. Analysis of epidemics of influenza in Russia conducted according to the Federal center for influenza on morbidity, hospitalization and deaths from influenza in 59 Russian cities. The epidemic of influenza A(H1N1)pdm09 2015–16 different from the mixed epidemics of influenza (A(H3N2) and B) 2014–15 and 2016–17 high development rate, high incidence of influenza and ARI at its peak, the incidence of hospitalization with a diagnosis of «influenza» (14%) and high mortality among the infected (6,0 on 100000). The epidemic of influenza A(H3N2) and B started earlier (December). They had a longer duration and the incidence in the cities and in the country, but less than the incidence at the peak of the epidemic and the incidence of hospitalization with a diagnosis of «influenza» (7.5 and 7.3%) and smaller (8.6 and 20 times) the mortality from the influenza. In these epidemics among the dead was higher than the percentage of children under 14 years and persons over 65 years of age than in the influenza epidemic 2015–16. And among the deaths increased the proportion of persons with chronic lung disease and immunodeficiency, but decreased the proportion of individuals with obesity and diseases of the liver and kidneys. For the period from 2009 to 2017 the tendency to increase the intensity of influenza A(H3N2) epidemics was 2.4 times greater than the decrease in the intensity of epidemic of influenza A(H1N1)pdm09.