Severity and Long-Term Mortality of COVID-19, Influenza, and Respiratory Syncytial Virus

Abstract

This cohort study showed that, during the 2022 to 2023 season, infection with SARS-CoV-2 was associated with more severe disease outcomes than influenza or RSV, whereas differences were less pronounced during the 2023 to 2024 season. During both seasons, RSV remained a milder illness, whereas COVID-19 was associated with higher long-term mortality. Vaccination attenuated differences in disease severity and long-term mortality.