[Distribution of respiratory pathogens in patients with pneumonia in Yinzhou, Ningbo, 2015-2024].

Objective: To describe the epidemiological characteristics of 22 common respiratory pathogens in patients with pneumonia in Yinzhou, Ningbo, from January 1, 2015 to December 21, 2024.

Methods: The test data of 22 common respiratory pathogens in patients diagnosed with pneumonia or lung infection in the Yinzhou Regional Health Information Platform from January 1, 2015 to December 21, 2024 were collected. The positive cases, positive rates, and positive proportions were calculated. The epidemiological characteristics were described by the year, sex, age group, season, and coronavirus disease 2019 (COVID-19) pandemic period.

Results: A total of 77 531 pneumonia patients were included, with 492 696 respiratory pathogen tests performed. The number of respiratory pathogen tests and positive cases of pneumonia patients in Yinzhou showed an upward trend. In the study, 34.63% of the pneumonia patients tested positive for at least one pathogen, and the pathogen non-detection rate decreased from 79.44% in 2015 to 58.38% in 2024. The overall pathogen positive rate was 9.12%, which decreased during the COVID-19 pandemic and had not returned to the historical level after the COVID-19 pande- mic. The positive rate was highest in children aged 6-17 years (13.99%), and lowest in the elderly over 60 years (4.16%). The top 3 highest number of positive cases was Mycoplasma pneumoniae, influenza A virus, and influenza B virus; the top 3 highest positive rates of pathogen tests were Mycoplasma pneumoniae (25.26%), rhinovirus (12.02%), and Bordetella pertussis (11.66%). The pathogen spectrum proportion in men was similar to that in women, only showing a higher ratio of Mycobacterium tuberculosis and a slightly lower ratio of Mycoplasma pneumoniae (P < 0.001). Mycoplasma pneumoniae, respiratory syncytial virus, and rhinovirus infections were more common in children, while influenza virus, Mycobacterium tuberculosis, and Streptococcus pyogenes infections were more common in adults and the elderly (P < 0.001). Influenza virus and human metapneumovirus infections were more common in winter, rhinovirus and Bordetella pertussis infections were more common in spring, and Mycoplasma pneumoniae infections were relatively more common in fall (P < 0.001). After the COVID-19 pandemic, the proportions of rhinovirus, respiratory syncytial virus, and human metapneumovirus infections in the pneumonia patients increased signi-ficantly, reaching 7.53%, 4.26%, and 2.25%, respectively, while the proportions of influenza B virus and Mycobacterium tuberculosis infections decreased to 4.14% and 2.80%, respectively (P < 0.001).

Conclusion: In the past decade, the scale of respiratory pathogen infection in the pneumonia population in Yinzhou had expanded significantly, and there were differences in distribution by the year, gender, age group, and season. The respiratory pathogen spectrum in pneumonia patients after the COVID-19 pandemic had a trend of diversification.