Investigation and traceability analysis of an acute gastroenteritis outbreak caused by norovirus

JIANG Ling, HUANG Mingyue, ZHANG Haixia, XU Liurong, XIA Junrui

Anhui Journal of Preventive Medicine ›› 2026, Vol. 32 ›› Issue (3) : 218-221.

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Anhui Journal of Preventive Medicine ›› 2026, Vol. 32 ›› Issue (3) : 218-221. DOI: 10.19837/j.cnki.ahyf.2026.03.009
Infectious Diseases Prevention and Control

Investigation and traceability analysis of an acute gastroenteritis outbreak caused by norovirus

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Abstract

Objective To investigate and analyze an outbreak of acute gastroenteritis that occurred in a company in 2025, identify the causative pathogen, explore its transmission characteristics and risk factors, and provide a scientific basis for the prevention and control of acute gastroenteritis outbreaks. Methods A combination of on-site epidemiological investigation and a case-control study was used to analyze risk factors. Case samples, environmental samples, and retained food samples were collected for culture of common pathogenic bacteria and real-time fluorescence quantitative PCR (RT-qPCR) detection of norovirus. Positive samples were sequenced and classified for homology analysis. Results A total of 374 individuals were investigated in the outbreak, among which 147 were cases, with an incidence rate of 39.30%. The main clinical manifestations were diarrhea (87.07%, 128/147). The distribution of cases showed spatial clustering.The attack rate of the department where the first case was found (55.26%) was significantly higher than that of other departments (χ2=20.295, P=0.028). The case-control study showed that the dinner on the evening of February 11th had no statistical association with the disease onset, and foodborne transmission was excluded.Molecular tracing revealed that the norovirus detected in the anal swabs from eight cases was of the same GⅡ.17[P17] type as that detected on the water faucet of the drinking dispenser, with a high homology of 99.45% to 100.00% in nucleotide sequence. Conclusion This epidemic was caused by norovirus GⅡ.17[P17] and was an outbreak of acute gastroenteritis mainly transmitted through person-to-person contact. It is recommended that collective units establish a symptom monitoring mechanism, strengthen disinfection of high-touch surfaces and improve employee health monitoring systems.

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Norovirus / Outbreak / Epidemiological investigation

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JIANG Ling , HUANG Mingyue , ZHANG Haixia , et al . Investigation and traceability analysis of an acute gastroenteritis outbreak caused by norovirus[J]. Anhui Journal of Preventive Medicine. 2026, 32(3): 218-221 https://doi.org/10.19837/j.cnki.ahyf.2026.03.009

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