More than 20 staff at Auckland's Middlemore Hospital have contracted norovirus.
The virus, which causes nausea, abdominal pain, vomiting and diarrhoea, has also hit Tauranga Hospital.
Middlemore spokeswoman Lauren Young said the hospital estimated that 23 staff had the virus which entered the hospital via a member of the public.
Young said the hospital is containing the virus using normal methods.
"People in contact with people infected are gowning and gloving," she said.
"We're also enforcing strict hand washing with hot water and soap, and not allowing children into the infected areas."
She said one ward in the hospital was restricted.
In Tauranga, around 30 patients have the virus, and the hospital there has closed four wards.
Bay of Plenty health officials have advised the public to avoid unnecessary trips to the hospital.
- Auckland Now
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