Multiple outbreaks of norovirus caused by persistent transmission in a hospitality setting in Victoria, Australia, 2023

This report describes unusually persistent transmission of norovirus in a hospitality setting in Victoria, Australia. In September 2023, the Victorian State Government Department of Health was notified of six gastroenteritis outbreaks associated with events held at a single function venue. Genomically identical norovirus genogroup II (GII) was detected from cases in five of the outbreaks. No statistically significant association with illness was found for any food item. Information collected through staff interviews provided evidence of food handlers and wait staff continuing to work while infectious, likely resulting in sustained transmission through person-to-person routes as well as through potential contamination of the environment.