Pathogen characteristics of respiratory infections in the season after the COVID-19 pandemic between August and December 2023: evidence from direct-to-consumer testing-based surveillance in Guangzhou and Beijing, China.

Objectives: In the fall-winter of 2023, China experienced its first epidemic season of respiratory diseases since the COVID-19 pandemic. Gathering timely data about pathogenetic characteristics of respiratory infections is crucial to complement current respiratory surveillance mechanisms in China. Data from direct-to-consumer (DTC) multi-respiratory pathogen (MRP) testing could serve as a novel source of multi-pathogen data for community-based surveillance.

Methods: A pioneering initiative was launched to detect multiple respiratory pathogens in Beijing and Guangzhou, China. DTC MRP tests were used to provide proactive surveillance ahead of medical services.

Results: A total of 28,018 participants were enrolled between 22 August and 10 December 2023. Positive findings for at least one respiratory pathogen were observed in 26,202 (93.5%) participants. Influenza virus A, respiratory syncytial virus (RSV), and human adenovirus are the three leading viral pathogens detected with proportions of 18.0%, 10.6%, and 8.8%. Viral-bacterial pathogens were co-detected in 9736 (34.7%) of participants, which reduced to 22.2% for bacterial-bacterial co-detection, and 22.0% for bacterial mono-detection. The epidemiological ecology of respiratory pathogens within both viral clusters and specific pathogens varied among cities. The peak of RSV epidemics in Guangzhou occurred in the fall of 2023, earlier than in Beijing.

Conclusion: The innovative program offered enhanced surveillance capabilities beyond traditional methods, enabling prompt feedback about test results and mitigating the risk of cross-infection caused by waits in healthcare facilities.