What is Norovirus?
{{Infobox medical condition (new) | name = Norovirus | synonyms = Winter vomiting bug,<ref name=NHS2018/> stomach bug | image = Norwalk.jpg | width = | alt = | caption = Transmission [[electron microscope]] image of Norwalk virus. The white bar = 50 [[nanometer|nm]] | pronounce = | field = [[Emergency medicine]], [[pediatrics]] | symptoms = [[Diarrhea]], vomiting, stomach pain, headache<ref name=CDC2016Sym/> | complications = [[Dehydration]]<ref name=CDC2016Sym/> | onset = 12 to 48 hours after exposure<ref name=CDC2016Sym/> | duration = 1 to 3 days<ref name=CDC2016Sym/> | types = | causes = ''Norovirus''<ref name=Yel2017/> | risks = | diagnosis = Based on symptoms<ref name=Yel2017/> | differential = | prevention = [[Hand washing]], disinfection of contaminated surfaces<ref name=CDC2017Pre/> | treatment = Supportive care (drinking sufficient fluids or [[intravenous fluids]])<ref name=CDC2017Tx/> | medication = | prognosis = | frequency = 685 million cases per year<ref name=CDC2017Glob/> | deaths = 200,000 per year<ref name=CDC2017Glob/><ref name=GBD2017/> }} '''Norovirus''' (or ''winter vomiting disease'') is a common cause of [[gastroenteritis]].<ref name=NHS2018>{{cite web |title=Norovirus (vomiting bug) |url=https://www.nhs.uk/conditions/norovirus/ |website=nhs.uk |access-date=8 June 2018 |date=2017-10-19 |archive-date=2018-06-12 |archive-url=https://web.archive.org/web/20180612143424/https://www.nhs.uk/conditions/norovirus/ |url-status=live }}</ref><ref name=CDC2017Glob>{{cite web|title=Norovirus Worldwide|url=https://www.cdc.gov/norovirus/worldwide.html|website=CDC|access-date =29 December 2017|language=en-us|date=15 December 2017|archive-url= https://web.archive.org/web/20181207142756/https://www.cdc.gov/norovirus/worldwide.html|archive-date=7 December 2018|url-status=dead}}</ref> It causes non-bloody [[diarrhea]] (enteritis), [[vomit