Incidence of acute respiratory infections and their associated pathogen distribution among residents in Shanghai, China: Preliminary results from community-based surveillance in the 2023-24 influenza season

Yilin Jia; Li Zhang; Yanxin Xie; Lipeng Hao; ChuChu Ye; Xinmei Zhou; Linghui Zhao; Bing Zhao; Yifeng Shen

doi:10.1016/j.ijid.2025.107974

Incidence of acute respiratory infections and their associated pathogen distribution among residents in Shanghai, China: Preliminary results from community-based surveillance in the 2023-24 influenza season

Int J Infect Dis. 2025 Jul 3:107974. doi: 10.1016/j.ijid.2025.107974. Online ahead of print.

Authors

Yilin Jia¹, Li Zhang¹, Yanxin Xie¹, Lipeng Hao¹, ChuChu Ye¹, Xinmei Zhou¹, Linghui Zhao¹, Bing Zhao¹, Yifeng Shen²

Affiliations

¹ Shanghai Pudong New Area Center for Disease Control and Prevention (Shanghai Pudong New Area Health Supervision Institute), Shanghai, 200136, China.
² Shanghai Pudong New Area Center for Disease Control and Prevention (Shanghai Pudong New Area Health Supervision Institute), Shanghai, 200136, China. Electronic address: yfshen@pdcdc.sh.cn.

PMID: 40617345
DOI: 10.1016/j.ijid.2025.107974

Abstract

Objectives: This study aimed to assess the risk of acute respiratory infections across distinct age demographics, analyze factors associated with infection and characterize respiratory pathogen epidemiology in the post-COVID-19 era.

Methods: We conducted this longitudinal community-based surveillance study in Pudong New Area from November 2023-January 2024. Questionnaires were designed to assess ARIs incidence, and respiratory pathogens were detected among qualified ARIs patients. Pathogenic features were compared and analysed among different age groups.

Results: A total of 6,698 participants were included and completed the study. The overall ARI incidence was 2.55(95%CI:2.42-2.68) per 1000 person-days. The incidence of ARI progressively decreased with increasing age. The factors significantly associated with infection were sex, employment as and chronic conditions among participants who reported symptoms. Influenza virus (IFV), Haemophilus influenzae (H. influenzae), human rhinovirus (HRV) and human coronavirus (HCoV) were the most commonly detected viruses. The positive distribution rate was similar among all age groups. The influenza virus trend maintained a prolonged peak period.

Conclusions: The incidence of ARI exhibited a progressive decline with advancing age. Community-based surveillance identifies respiratory pathogen profiles during early or mild infections, complementing routine surveillance.

Keywords: Acute respiratory infections; Respiratory pathogens; community-based surveillance; incidence.