Cross-sectional Study About Respiratory Viruses and the SARS-CoV-2 Pandemic in Southern Brazil: Results of a Prospective Epidemiologic Active Surveillance Study.

BACKGROUND

The coronavirus disease pandemic has deeply impacted various societal sectors, altering the distribution patterns of community respiratory viruses. As children and teenagers are commonly affected by these viruses, monitoring infections within these groups can provide insights into viral dynamics during periods with and without pandemic containment measures.

METHODS

This study used data from an ongoing active epidemiological surveillance program that included hospitalized children with acute respiratory illnesses from Curitiba, southern Brazil. Data were collected over 3 years, from 2020 to 2022. Cases were classified as severe or nonsevere based on clinical and laboratory findings.

RESULTS

A total of 1636 children participated in the study. Respiratory syncytial virus was the most prevalent (22%), followed by the human rhinovirus (13%). Respiratory syncytial virus and human bocavirus were significantly associated with severe disease, whereas adenovirus was less common in severe cases. Atypical seasonal patterns were observed during the study period. No significant difference in severity was found for SARS-CoV-2 infected patients.

CONCLUSION

Community respiratory viruses circulation was significantly reduced in the first year of the coronavirus disease-19 pandemic, and the subsequent 2 seasons exhibited a new pattern of viral seasonality. Further studies are required to understand the mechanisms underlying these changes.