Epidemiological characteristics of community-acquired pneumoniae in hospitalized children around COVID-19 from Jiangsu Province, China: a multicenter retrospective study.

Background: It has been reported that the emergence of coronavirus disease 2019 (COVID-19) has changed the epidemiological characteristics of many pathogens, but the epidemiological characteristics of (MP) infection in hospitalized children with community-acquired pneumonia (CAP) are not clear. The aim of this study was to answer this question.

Methods: Children with CAP in three tertiary hospitals (hospitals A, B and C) from 2018 to 2023 were selected. Data on gender, age, number and date of MP infection were obtained from the medical record. The intensity of the epidemic was measured as a percentage of the number of CAP.

Results: In hospitals A and B, before the pandemic (in 2018 and 2019), the number of hospitalized children with MP pneumonia and the proportion of total pneumonia had shown a significant upward trend, but the control measures led to a slight decline. In hospital C, the number and percentage of hospitalized children with MP pneumonia were low before and during the COVID-19 period. After the epidemic control was lifted, the number and percentage of children with MP pneumonia in the three hospitals increased sharply, and the proportion of children aged more than 7 years old increased significantly in 2022 and 2023.

Conclusions: From 2018 to 2019, there was already an epidemic trend of MP in the study hospital. From 2020 to 2022, after the outbreak of COVID-19, the incidence of MP pneumonia stabilized, but after the epidemic control was lifted, it broke out. This may be due to the severe restrictive measures taken early during the COVID-19 pandemic that effectively controlled the spread of MP, pausing its pandemic.