Abstract
OBJECTIVE: To investigate the distribution of pathogens and epidemiological changes in children hospitalized with community-acquired pneumonia (CAP) during and after the COVID-19 pandemic public health restrictive measures. aiming to provide a foundation for clinical diagnosis, treatment, and policy formulation. METHODS: This multicenter retrospective study spanned January 2019 to December 2023. The study included 78,256 children hospitalized for CAP in four hospitals in Henan, China, among which 27,580 cases (35.2%) were tested for pathogens using multiplex real-time fluorescent polymerase chain reaction (PCR). The pathogens detected include Streptococcus pneumoniae (SP), Staphylococcus aureus (SA), Haemophilus influenzae (HI), respiratory syncytial virus (RSV), influenza A virus (Flu A), influenza B virus (Flu B), and Mycoplasma pneumoniae (MP). RESULTS: Pathogens were identified in 18,690 of the 27,580 children, resulting in a 67.8% positive detection rate. Of these cases, 15,105 (54.8%) were single pathogen infections and 3,585 (13%) were mixed pathogen infections. The pathogen positivity rate was lowest in the first year of the COVID-19 pandemic (2020), at 54.7%, and peaked at 79.1% in 2023, after public health restrictions were lifted. During the COVID-19 pandemic (2020-2022), seasonal variation in pathogen prevalence was disrupted. Post-restriction, there was a significant increase in RSV and MP cases. SP remained the leading bacterial cause of CAP, especially in young children. RSV was the predominant viral pathogen, particularly affecting infants. MP showed a rising trend with age, yet it also affected younger individuals. CONCLUSION: The COVID-19 pandemic altered the epidemiological characteristics of pathogens in children with CAP. This impact is likely to persist, necessitating enhanced surveillance of CAP pathogens to mitigate the healthcare burden in children. CLINICAL TRIAL NUMBER: Not applicable.