Respiratory syncytial virus contributes to more severe respiratory morbidity than influenza in children < 2 years during seasonal influenza peaks

Abstract

Purpose: To compare the frequency and the severity of influenza and respiratory syncytial viruses (RSV) infections among children < 24 months hospitalized with respiratory symptoms. Methods: Data from a prospective study conducted during the peak of five influenza seasons in the Province of Quebec, Canada were used. Results: We detected higher frequency of RSV compared to influenza viruses (55.3% vs. 16.3%). Radiologically confirmed pneumonia was significantly more frequent in children with RSV (39%) than those with influenza (18%) and the clinical course was more severe in RSV than influenza-infected children, especially among infants < 3 months. Conclusion: Even during peak weeks of influenza season, we found a higher burden and severity of RSV compared with influenza virus disease in hospitalized children < 24 months.