There are six new cases of Covid-19 in New Zealand, all of which are linked to the Mt Roskill "mini-cluster", director-general of health Ashley Bloomfield says.
A person who works at Auckland's Māori public health unit, Hapai Te Hauora, has tested positive for Covid-19.
The Auckland Regional Public HealthService today confirmed a person at Hapai is now a confirmed case.
The public health service yesterday sent a letter to everyone in the Whanau Centre building in central Henderson where the infected person works.
The service said it had worked with the Covid-positive person at the west Auckland office and fellow colleagues at the health unit to identify close contacts.
The person at the centre of the health scare was now in isolation along with their household, with the risk to everyone else in the building described as "very low".
Everyone considered a close contact has been contacted by health authorities and been told to isolate for 14 days.
Those who work in the same high-rise building on Pioneer St are also being told while there is a confirmed case, they are unlikely to fall ill if they are not a close contact.
The letter to office workers across the site warns that as there are current cases in the community, it remains important to be vigilant for signs of the virus.
The building contains a number of vital community health services including a dentist, a pharmacy, Covid-testing site, addiction support and cancer care service.
The Unichem Waiora Pharmacy remained open and serving customers today.
Hapai Te Hauora released a statement confirming an employee and household members were in isolation and would remain so until cleared by public health.
The risk to other Hāpai Te Hauora staff not identified as close contacts, and those employees who worked for other organisations in the same building, was considered very low, said the organisation.
Meanwhile, another case reported yesterday, also part of the new sub-cluster, was a driver on the Northern Express bus service. That bus travels between the central city and at least as far as Albany.
Auckland regional public health said there were no close contacts on the relevant bus journeys, and the driver was not symptomatic at the time, but was also wearing a mask.
HOP card data will also be used to identify passengers as a precaution, Bloomfield said said.
The public health unit will later reveal details of the bus journeys.
It comes as a West Auckland college is closed and parents with children at nearby schools are being asked to keep their children home if there are siblings who attend St Dominic's Catholic College after a senior student tested positive.
Another pupil at nearby Henderson North School is in self-isolation and has been tested, but remains well and was very unlikely to have been infectious when last at school.
The cases are linked to the Mt Roskill Evangelical Fellowship church sub-cluster that has swollen to 37 positive cases this week.
Today, Health Minister Chris Hipkins revealed some close contacts of the Mt Roskill church sub-cluster were not previously disclosed, including the student that recently tested positive.
It appeared in this case she was a close contact of the sub-cluster that had not been previously disclosed.
The authorities were now looking into whether that was on purpose.
"That's one of the things that the investigation is looking at now and it will include looking at whether there was a deliberate decision not to disclose, or whether it was simply an oversight," Hipkins said.
Hapai is a non-clinical, non-client facing public health service and delivers policy, advocacy, research and leadership services across Aotearoa.
The organisation has held the regional Māori public health contract for Tāmaki Makaurau for 20 years, providing a strategic focus for communities to enjoy good health and to be sustained by healthy environments.
The person, and their household members, were to remain in isolation and self-isolation until cleared by public health, said a spokesperson.
The risk to other Hāpai Te Hauora staff not identified as close contacts, and those employees who worked for other organisations in the same building, was considered very low.
