Changing patterns of respiratory pathogens in hospitalized children with community-acquired pneumonia in northern China following the lifting of non-pharmaceutical interventions

An observational, single-center study was conducted among hospitalized children with community-acquired pneumonia in the Baoding area. The objective was to compare the respiratory pathogen profiles and epidemiological patterns during and after the lifting of non-pharmaceutical interventions (NPIs, including mask-wearing, social distancing, lockdowns, etc.). A total of 9,362 hospitalized children diagnosed with CAP in Baoding from January 2022 to December 2023 were included. Both viral and bacterial pathogens were detected by multiplex PCR. The NPIs were lifted in Baoding from 2 December 2022. A comparative analysis was conducted on demographic data, epidemiological data, pathogen detection rates, and co-infection patterns that were compared between the full year 2022 and 2023. The detection rate of at least one pathogen significantly increased from 74.2% (2,925/3,940) in 2022 to 86.5% (4,690/5,422) in 2023 (<i>P</i> < 0.001). <i>Mycoplasma pneumoniae</i>, <i>Streptococcus pneumoniae</i>, human rhinovirus, respiratory syncytial virus (RSV), and <i>Haemophilus influenzae</i> were the predominant pathogens. Notably, co-infection rates rose from 25.1% (988/3,940) in 2022 to 45.1% (2,445/5,422) in 2023 (<i>P</i> < 0.001), particularly viral-bacterial co-infections. The positive detection rates for many pathogens among severe pneumonia cases increased. Additionally, an age shift in infection patterns was observed, with older children showing a higher prevalence of RSV. Following the lifting of NPIs, an increase in the detection rates of pathogens was observed, as were fluctuations in the dynamics of viral and bacterial pathogens, underscoring the urgent need to adapt clinical management and public health policies to address emerging infection trends. IMPORTANCE Community-acquired pneumonia (CAP) remains the leading infectious cause of death in children worldwide. Understanding the pathogens responsible for CAP is essential for effective diagnosis and treatment. This study examines the changes in respiratory pathogens and epidemiological patterns in children with CAP in Baoding, China, before and after the lifting of non-pharmaceutical interventions (NPIs). Data from 9,362 children diagnosed with CAP from January 2022 to December 2023 were analyzed. The detection rate of at least one pathogen increased significantly from 74.2% in 2022 to 86.5% in 2023. Notably, co-infection rates rose from 25.1% to 45.1%, with viral-bacterial co-infections being more common. This research underscores the urgent need to adapt clinical management and public health policies to address the changing infection trends, highlighting their importance and innovation in understanding the impact of NPIs on pediatric respiratory infections.