Peculiarities of acute viral respiratory infections pathogens epidemiology and circulation in some regions of the Russian Far East during two epidemic seasons (2017-2018 and 2018- 2019 years)

Abstract

Aim. To reveal peculiarities of acute respiratory viral infections (ARVI) incidence among population of the Far Eastern Federal District depending on viral etiology during two epidemic seasons (2017-2018 and 2018-2019). Materials and methods. Method of epidemiological analysis by means of ARVI incidence with weekly epidemic thresholds as utilized. Laboratory diagnosis of respiratory viruses was carried out by applying RT-PCR method and test-kits of the Central Research Institute of Epidemiology. In order to determine relations between ARVI incidence and viral etiological structure of ARVI correlation and regression analysis was performed. Results. Identical epidemical tendencies with differences in ARVI incidence intensity were registered in the evaluated constituent entities of the Russian Far East. Utmost intensity of epidemic process was revealed in the Republic Sakha (Yakutia) and Sakhalin Oblast. In the south regions (Khabarovsk and Primorsky Krai, Amur Oblast) ARVI incidence, occasionally excessing epidemic threshold was lower. Territorial and time irregularity is peculiar for etiology of infections in the Russian Far East. During the epidemic season of 2017-2018 statistically significant prevalence was determined for the influenza virus B in Primorsky and Khabarovsk Krai, influenza virus A(H3N2) ‒ in the Sakhalin Oblast, respiratory syncytial virus ‒ in the Republic Sakha (Yakutia), rhinoviruses were dominant in the Amur Oblast. During the 2018-2019 epidemic season influenza virus A(H1N1)pdm09 was mostly prevalent in most of the constituent entities of the Russian Far East. Compared to the other regions of the Far Eastern Federal District in the Amur Oblast were revealed differences in circulation of respiratory viruses predominantly of non-influenza origin during two observed epidemic seasons. Conclusion. Constant evaluation of ARVI epidemics under the conditions of constantly changing landscape of circulating viruses in a particular region can be useful for determination of strategies and tactics of epidemiological response.