A total of 74 people have become ill after visiting a hotel in Newport.
An investigation is being carried out after 51 guests and 23 staff were affected by a viral infection, which is probably norovirus, at the Hilton Hotel in Langstone.
They started to become ill last Tuesday and suffered diarrhoea and vomiting.
Hilton Worldwide said the wellbeing of guests and staff was of “paramount importance” and it had brought in “stringent” health and safety measures.
Public health officials say the outbreak is not linked to a particular function or event, but the virus was passed by someone originally infected.
Newport council alerted Public Health Wales two days after the first illnesses.
Virus outbreak hits Wellington childcares, resthomes
Outbreaks of norovirus and rotavirus have been reported at Wellington childcare centres and resthomes.
Regional Public Health had responded to outbreaks of gastroenteritis at four childcare centres and two rest homes since the beginning of the month, medical officer of health Jill McKenzie said.
The number of outbreaks was higher than usual and indicated stomach bugs were circulating in the community.
“The nature of these bugs is they don’t tend to infect one person because their viruses are quite infectious.
