Norovirus is the leading cause of acute gastroenteritis in the United States. In April 2020, the incidence of norovirus outbreaks in the United States declined substantially, likely because of implementation of COVID-19–related nonpharmaceutical interventions, such as facility closures, social distancing, and increased hand hygiene. Similar declines were observed in other countries (3,4). Norovirus outbreaks in the United States increased rapidly starting in January 2022, approaching prepandemic (i.e., 2012–2019) levels. Norovirus transmission can be prevented by thorough handwashing and proper cleaning and disinfection of contaminated surfaces.
