This year, as of January 8, a total of 13 diarrhea clusters have been reported and a total of 679 people developed symptoms. Of the 13 clusters, 2 clusters are tested positive for norovirus and the test results of the other 11 clusters are still pending. Most clusters occurred in schools, followed by the hospitality industry. During the same period in 2016, a total of 10 diarrhea clusters were reported and 80 people developed symptoms. 9 clusters were tested positive and 8 were associated with norovirus. As norovirus becomes more active during the winter months, the public is reminded to pay attention to personal and dietary hygiene. Schools and restaurant workers are urged to strengthen prevention measures in order to prevent outbreaks.

According to the surveillance data compiled by Taiwan CDC, during the past four weeks (Weeks 50 and 53 in 2016 and Week 1 in 2017), the majority of the acute gastroenteritis clusters (76%) caused by norovirus were reported in schools, 12% were reported within the hospitality industry, and the rest were reported in offices, highly populous institutes, households and tutoring center. In addition, the proportions of patients seeking emergency department for acute gastroenteritis during the past four weeks respectively are 3.86%, 4.07%, 4.32%, and 5.14%. Acute gastroenteritis activity has been on the rise.

On the other hand, acute gastroenteritis activity around the world has also been on an increasing trend. The majority of the acute gastroenteritis outbreaks recently occurred in Japan and Korea were associated with norovirus. During January and November, 2016, a cumulative total of 82 infectious diarrhea clusters were reported and 74% were caused by norovirus. The outbreaks primarily occurred in Guangdong Province, Chongqing City, Jiangsu Province, Shandong Province, Hunan Province and Zhejiang Province, and they mostly occurred in schools and nursing institutes. As Guangdong Province observed a significant increase in norovirus clusters since December 2016, the local competent authority issued an early warning on norovirus. Moreover, UK has also recently reported an increase in the number of norovirus infections. Beginning July 2016, a cumulative total of 2,600 cases have been reported, which is 8% more than that during the same period in the past 5 years.

Norovirus infection is transmitted mostly through fecal-oral route. Viruses can survive in the vomitus and stool of infected people for a long time and infect others through the consumption of virus-contaminated food or close contact with the patients. As a result, large scale outbreaks often occur.　The public is urged to pay attention to the source of ingredients used in home-cooked meals and ensure the cooking process is hygienic. In addition, infected individuals should rest at home, and only resume school or work 48 hours after symptoms are relieved to lower the risk of transmission through direct contact. If the patient is unable to take leave, please put on a mask and refrain from touching nose and mouth with hands to prevent further spread of the disease. Further, washing hands frequently and maintaining personal and environmental hygiene are important measures to take to ward off infection. For more information, please visit the Taiwan CDC website at http://www.cdc.gov.tw or call the toll-free Communicable Disease Reporting and Consultation Hotline, 1922 (or 0800-001922).