Enteroviral infection in Ural Federal District and West Siberia: results of epidemiologic observation involving molecular-genetic methods

The objective of this work was to reveal the incidence patterns of enteroviral infection (EVI) in the constituent territories of Ural Federal District (UFD) and West Siberia in modern times. Materials and methods. We used the data from forms of federal statistical EVI monitoring for the period from 2017 to 2019 as well as those from the epidemiological investigation reports obtained from the disease clusters. The genotype of the enteroviruses was determined in specimens of biomaterial from 1,213 patients and their contacts using the molecular genetic method. Results and discussion. In most of the regions presented, an unfavourable epidemic situation with a trend towards further increase in the incidence still remains. Enteroviral infection has typical estivo-autumnal seasonality and age structure. Its most common clinical form is exanthematous lesion of skin and mucous membranes. The intensity and dynamics of the disease clusters formation closely correlates with the level and seasonal dynamics of the EVI incidence in the given area. A total of 36 enterovirus genotypes were detected. Most of the typed strains belonged to species A (39.8 %) and В (55.1 %), and their ratio did not change considerably from 2017 to 2019. However, the intraspecific type structure was subject to major variation. Conclusion. In most regions of UFD and West Siberia, an unfavourable epidemic situation with EVI with a trend towards further increase in the incidence still remains. Genotyping of the detected strains with subsequent phylogenetic analysis permitted more precise identification of the spectrum of the imported enterovirus strains and of those endemic for a specific area as well as evaluating the rate of their spread and their epidemic potential. Studying the variability of the enteroviral population demonstrated high intraspecific dynamics of the genotypes that maintains the intensity of the epidemic. Importation of new genovariants of Coxsackievirus B5 and echoviruses-30 and-11 with a high epidemic potential into the territory of UFD and West Siberia deserves particular attention.

enterovirus infection, enterovirus, epidemiological analysis, molecular genetic studies, Urals Federal District, Western Siberia

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