Molecular epidemiology of respiratory viral infections in hospitalized children in Novosibirsk, Russia, 2021–2023
TL;DR
The epidemiology of the analyzed viruses was consistent with worldwide surveillance trends and largely stable between the two later epidemic seasons, and in viral-bacterial association analysis the authors identified two significantly attracted pairs, in which virus is known to facilitate bacterial adherence to respiratory epithelium.
Abstract
Background Acute respiratory infections (ARIs) are among the leading global causes of morbidity and mortality in children. While viral agents of ARI are rigorously monitored, other pathogenic organisms and pathobionts — bacteria and fungi native to the host microbiome — remain largely neglected. Adenoviral types also warrant particular attention especially given the widespread use of adenoviral vector vaccines during the COVID-19 pandemic. Methods Oro-nasal swabs collected from 1679 children under the age of 18 hospitalized in Novosibirsk, Russia between February 2021 and June 2023, were tested for the presence of nucleic acids by the diagnostic panel targeting 17 viruses, 12 bacteria and one yeast. Adenovirus-positive samples were additionally fine-typed by Sanger sequencing. Results Overall, 79.15% of samples were positive for at least one of 17 viral pathogens, with RSV (22.87% positives) and RhV (24.54% positives) dominating the etiological structure. Oro-nasal presence for respiratory pathobionts and opportunistic pathogens was 67.96% and 11.49%, respectively. Generally, viral seasonality was typical for continental climate, with only two notable deviations: MpV absence in spring of 2022 followed by earlier December peaks in the same year; an earlier RSV maximum in October 2021 with extended circulation the next epidemic season. Overall, the epidemiology of the analyzed viruses was consistent with worldwide surveillance trends and largely stable between the two later epidemic seasons. In viral-bacterial association analysis we identified two significantly attracted pairs, in which virus is known to facilitate bacterial adherence to respiratory epithelium. Adenovirus fine-typing provided preliminary evidence that serotypes 1, 2, 3, and 7 are the most frequently detected among the typed samples, while vaccine serotype AdV-5 was identified in only two cases. Conclusion Broad target coverage allowed for a comprehensive analysis of epidemiological patterns, highlighting a trend toward stabilization of the etiological structure to pre-pandemic levels, and allowed for prioritization of clinically relevant viral-bacterial associations. Preliminary findings in adenoviral fine-typing are consistent with global trends in serotype prevalence and help address an important gap in regional adenoviral epidemiology.