Pathogenic changes of community-acquired pneumonia in a children’s hospital in Beijing,China before and after COVID-19 onset:a retrospective study

Background This study aimed to analyze the pathogenic characteristics of community-acquired pneumonia(CAP)in a children’s hospital before and after the coronavirus disease 2019(COVID-19)pandemic and to provide testimony for preventing CAP in the future.Methods A retrospective analysis was performed.The information was collected from the electronic medical record system of the hospital.A total of 2739 children were included from February 1,2019,to January 31,2021.Results Among these 2739 patients were 1507(55.02%)males and 1232(44.98%)females;the median age was 3.84 years.There were 2364 cases during the pre-COVID-19 period and 375 cases during the post-COVID-19 period.The number of hospitalized children after the pandemic was 84.14%lower.The median age after the onset was 1.5 years younger than that before the onset(4.08 years old)(Z=−7.885,P<0.001).After the pandemic,the proportion of CAP in school-age children and Mycoplasma pneumoniae pneumonia(MPP)and influenza virus pneumonia(IVP)decreased significantly.During the pre-COVID-19 period,the proportions of detected pathogens were as follows:MP(59.56%)>bacteria(50.42%)>viruses(29.57%)>fungi(3.43%).During the post-COVID-19 period,the pathogen proportions were bacteria(56.53%)>viruses(53.60%)>MP(23.47%)>fungi(3.73%).Conclusions There was a significant decrease in the number of children with CAP hospitalized after the pandemic,especially among school-age children,and the pathogen proportions of CAP with MP and IV were significantly decreased.We inferred that CAP was effectively prevented in school-age children because of the strong mitigation measures.