Assessment of group incidence of noroviral infection in the territory of Omsk region with genotype analysis

Norovirus is a common cause of epidemic and sporadic acute gastroenteritis in many regions of Russia. It was decided to assess the outbreak incidence of acute viral intestinal infections with the isolation of the proportion of norovirus gastroenteritis and an analysis of its genotyping in the Omsk region. Materials and methods. The study used the results of the main reporting forms on the incidence of acute intestinal infections in the Omsk region for the period between 2016 and 2023. The results of genotyping of circulating strains of noroviruses in the Omsk region were provided by the reference center for monitoring pathogens of intestinal infections in Russia. Study results. All outbreaks of acute intestinal infection were of viral etiology. Most of them were registered in preschool institutions. The contact and household transmission route prevailed. Norovirus gastroenteritis was diagnosed in half of all cases. The source was most commonly an infected person or a virus carrier. Genotyping revealed a circulation of various strains, but with a prevalence of GII in 81.6%. The dominance of GII.P16 was noted for several years. Norovirus strains already recorded in some regions of Russia were determined. Conclusion. Viral diarrhea remains the leading cause of intestinal infections in individuals under 17 years of age. The circulation of noroviruses in the region leads to the emergence of infection foci in groups of children. Long-term genotyping of norovirus is necessary to control the circulation of new or recurrent variants, which will allow for further development of effective specific preventive measures.