Five-year surveillance of pediatric respiratory pathogens in Fuzhou (2019–2024): impact of the COVID-19 pandemic

This study aims to investigate the epidemiological characteristics and distribution patterns of respiratory pathogens in children in Fuzhou between 2019 and 2024, with a particular focus on changes associated with the COVID-19 pandemic. This retrospective study included children aged 0–18 years hospitalized for acute respiratory infections in Fuzhou Children’s Hospital of Fujian Province between June 2019 and May 2024. Nasal swab specimens were collected to test for 11 respiratory pathogens using multiplex PCR. The distribution characteristics of pathogens were analyzed across age groups, genders, seasons, and pandemic phases. A total of 37,724 nasal swab specimens were included, comprising 22,327 males and 15,397 females. The overall test positivity rate was 58.78%. Rhinovirus had the highest positivity rate (20.95%), followed by respiratory syncytial virus (11.12%) and Mycoplasma pneumoniae (6.89%). Co-infections were identified in 8.08% of specimens. Multivariable logistic regression revealed distinct age, sex, and seasonal patterns for the three most common pathogens: M. pneumoniae risk increased progressively with age (≥ 6 years: OR = 6.100), RSV predominated in infants, and rhinovirus showed a less pronounced age pattern. Across four pandemic phases (pre-pandemic, strict NPIs, transition, and post-restriction), pathogen detection exhibited distinct trajectories. M. pneumoniae dropped sharply during the pandemic period and resurged post-restriction (from 1.11% to 12.61%); rhinovirus declined during strict NPIs but rebounded quickly and remained stable; RSV paradoxically increased during strict NPIs (from 10.66% to 26.74%). This study provides evidence on pediatric respiratory pathogen epidemiology in Fuzhou, revealing pathogen-specific changes in detection patterns across different pandemic phases. These findings underscore the importance of continued surveillance and pathogen-targeted prevention strategies in the post-pandemic era. Not applicable.