Gastroenteritis Outbreak in Tour Groups, Lyudao, 2015

DOI: 10.6525/TEB.20160719.32(14).002

Wen-Wen Huang1*, Hao-Yuan Cheng1, Fang-Tzy Wu2, Che-Yuan Chang2, Lin-Ching Huang3, Hsu-Yang Lin4, Che-Yang Lin4, Tsung-Yen Liu4

2016 Vol.32 NO.14

Correspondence Author: Wen-Wen Huang1*

  • 1Eastern Regional Center, Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 2Diagnostic and Vaccine Development Center,Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 3Office of Preventive Medicine, Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 4Division of Research & Analysis, Food and Drug Administration, Ministry of Health and Welfare,Taiwan


In May and June 2015, four and seven diarrhea outbreaks among tour groups traveling to Lyudao Township were reported. A common source for these outbreaks was suspected because of a single epidemic peak observed in every outbreak. Norovirus was detected in the samples both from patients’ stool and oysters provided by restaurant A. Judged from the norovirus incubation period, all patients had food provided by restaurant A. The temporal evidence also suggested the contaminated oysters in restaurant A caused the outbreaks. Further sequencing analysis showed that the norovirus detected from patients and oysters belonged to the same group and confirmed the assumption. This is not the first time that oysters imported from Korea caused gastroenteritis outbreaks. Similar outbreak had occurred once in relation to one famous buffet restaurant in 2012. To decrease the risk of outbreak, relevant authorities should strengthen the regulation for importation of oysters, evaluate the high-risk place of origin, and enhance associated training and on-job education for the food and beverage industry.

Keywords:Norovirus, Diarrhea outbreak