Covid-19 Response Minister Chris Hipkins says the unvaccinated Auckland security guard who tested positive for Covid-19 had been offered a vaccination shot several times.
Hipkins told Newstalk ZB's Heather du Plessis-Allan that several attempts had been made to offer the Grand Millennium worker a vaccine but they hadn't been successful.
"Part of the interview process that we are going through today is to understand why," Hipkins said.
"Was it that the person refused, or were they unable to for a variety of reasons?"
Prime Minister Jacinda Ardern today said it was too risky to leave unvaccinated border workers in jobs where they might contract Covid-19 from those arriving from overseas.
That included workers at managed isolation facilities, airports and ports.
Frontline border workers will start being moved into "low risk" roles from Monday if they refuse to get vaccinated, she said.
So far more than 80 per cent of frontline workers had been vaccinated, Ardern said.
Four people who live in an adjourning house to the new case have all tested negative today.
A co-worker who often drove the man to and from work has also returned a negative result.
The Ministry of Health said it understood the guard missed two appointments for vaccination for "personal reasons".
"We know that the company employing this case has vaccinated 79 per cent of its MIF [managed isolation facility] workers and 81 per cent of the Grand Millennium staff have received their first vaccination."
Testing of staff at the Grand Millennium has now been increased to weekly for the next fortnight and a spot infection control audit has been undertaken today.
The ministry believes risk to the wider community from the latest case is low.