A Corrections staff member at the Spring Hill Corrections Facility has been confirmed as one of Tuesday's new community COVID-19 cases.
Prime Minister Jacinda Ardern and Director-General of Health Dr Ashley Bloomfield announced at the 1pm COVID-19 update there are 49 new coronavirus cases on Tuesday.
One of the new cases is a Corrections staff member at Springhill Prison in Te Kauwhata, Waikato who is asymptomatic.
"This person had identified themselves as having been at a location of interest and immediately isolated and got tested," Dr Bloomfield said.
"Corrections were informed last night and, suffice to say, under alert level four they already have very strict protocols around minimum contact between staff and inmates and also use of PPE."
Ardern confirmed the officer is fully vaccinated.
Dr Bloomfield said the 23 staff members who had been at the facility at the same time as the staff member have been isolating and are getting tested. The 123 people who were in the unit the staff member was in have also been segregated and are being tested.
Health authorities are now considering testing the wastewater of the facility.
In a statement after the press conference, Minister of Corrections Kelvin Davis said the case "did the right thing" after realising they had visited a location of interest.
"Despite showing no symptoms they went and got tested and I want to thank them for their vigilance," he said.
Davis said Corrections had been planning for a potential case for "some time" so were prepared for when it happened.
"I have full confidence that their thorough plans will limit any spread of the virus within the prison.
"I expect to be kept fully informed as this situation develops, including updates on the welfare of both staff and prisoners at Springhill.
"This will be an unsettling time for many at the prison and I want to acknowledge the frontline staff going to work every day while we try to eradicate the virus."