ORIGINAL RESEARCH article
Front. Public Health
Sec. Infectious Diseases: Epidemiology and Prevention
Volume 13 - 2025 | doi: 10.3389/fpubh.2025.1631091
Investigation of a norovirus outbreak among hospital staff in Zhejiang, China: Tracing the source to contaminated "red bean cake"
Provisionally accepted
- Institute of Infectious Disease Control and Prevention Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution), Hangzhou China, China
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
While nosocomial norovirus transmission in hospitalized patients is well characterized, its transmission dynamics among HCWs remain poorly documented. This investigation of HCW-focused norovirus transmission provides critical epidemiological evidence to refine infection control protocols for gastroenteritis in healthcare settings. This study utilized a retrospective case-control design to systematically analyze outbreak transmission dynamics. Structured questionnaires were implemented ≤72 hours post-symptom onset to capture dietary exposures during the three-day exposure window, minimizing recall bias. Potential high-risk dining periods and food items were further analyzed via a case-control study. The outbreak investigation identified 52 cases, including 48 HCWs and 4 cafeteria staff, yielding an overall attack rate of 2.21% (52/2352). Epidemiological evidence supports a point-source origin, as demonstrated by the single-peak epidemic curve. Case-control analysis revealed the lunch on 19th June as the primary exposure window (statistically significant OR = 25.21; 95% CI: 3.35–189.69), with the "red bean cake" served in the implicated meal being the significantly associated food item (OR = 1248.75; 95% CI: 170.64–9138.33). RT-qPCR confirmed norovirus GII RNA in clinical specimens from cases and the implicated "red bean cake" food sample. These findings definitively established the "red bean cake" as the outbreak's etiological source.
Keywords: Norovirus, Healthcare workers, case-control study, outbreak investigation, Source tracing
Received: 19 May 2025; Accepted: 14 Jul 2025.
Copyright: © 2025 Duan, Wang, Wang, He, Ren, Wang, Kao, Song and Huo. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
Xiaojian Duan, Institute of Infectious Disease Control and Prevention Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution), Hangzhou China, China
Kai Song, Institute of Infectious Disease Control and Prevention Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution), Hangzhou China, China
Liangliang Huo, Institute of Infectious Disease Control and Prevention Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution), Hangzhou China, China
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.