Changes in the major pathogen spectrum of community-acquired pneumonia in children before and after the COVID-19 epidemic and influencing factor analysis

Objective To observe the changes in the composition of the main pathogens of community-acquired pneumonia (CAP) in children before and one year after the COVID-19 February 2020, and analyze the susceptible factors to CAP infection. Methods A total of 2 446 CAP children were enrolled and their clinical data were retrospectively analyzed. They were divided into a pre-COVID-19 group (admission before February 1, 2020) and a COVID-19 group (admission after February 1, 2020). Their pathogen profiles were compared and the susceptible factors of pathogen infection were analyzed. Results No statistical difference was found in the positive detection rate of CAP pathogens between the two groups (P>0.05). Pathogens detected in both groups were mainly atypical pathogens, especially Mycoplasma pneumoniae, followed by viruses and bacteria. In the COVID-19 group, the top three pathogens included Mycoplasma pneumoniae, respiratory syncytial virus, and cytomegalovirus, compared with the top three pathogens Mycoplasma pneumoniae, cytomegalovirus, and Epstein-Barr virus before the COVID-19 epidemic. The COVID-19 epidemic group showed higher proportions of virus, adenovirus, coxsackie B and Chlamydia and lower proportions of respiratory syncytial virus than the pre-COVID-19 epidemic group. The COVID-19 epidemic group also presented significantly higher proportions of G⁺ bacteria and G^- bacteria, as well as Staphylococcus aureus and Klebsiella pneumoniae than the pre-COVID-19 epidemic group (P<0.05). According to multivariate analysis, age <1 year old, vaginal delivery, heart disease, and respiratory disease were the risk factors for bacterial infection in the pre-COVID-19 group, while vaginal delivery, premature birth, anemia, and abnormal liver function were the risk factors for bacterial infection in the COVID-19 group. Cesarean section, age<1 year, no neutropenia, and not living in Xuzhou urban area were the risk factors for viral infection in the pre-COVID-19 group, while not living in Xuzhou urban area, anemia, and abnormal liver function were the risk factors for viral infection the COVID-19 group. Full term, female babies, and age ≥ 1 year were the risk factors for atypical pathogen infection in the pre-COVID-19 group, while age ≥ 1 year was the risk factor for atypical pathogen infection in the COVID-19 group. Conclusions During the COVID-19 epidemic, the pathogenic spectrum of CAP in children of Xuzhou area is changed, where the proportion of viruses significantly decreases and the proportion of bacteria increases, compared with those before the COVID-19 epidemic, and no statistical difference was found in atypical pathogens. Mycoplasma pneumoniae, respiratory syncytial virus, and cytomegalovirus are the main pathogens during the COVID-19 epidemic. The pathogen susceptible factors are different before and after the COVID-19 epidemic.