Patterns in the dynamics of respiratory viruses after the COVID-19 pandemic: an observational, retrospective study using sentinel surveillance network data, Catalonia, 2022 to 2025
BACKGROUND Respiratory viruses are a major cause of morbidity and mortality worldwide. Their circulation patterns were markedly altered by the COVID-19 pandemic. The Information System for Infection Surveillance in Catalonia (SIVIC), established in 2022, provides continuous, population-representative sentinel surveilla...