New Zealand has had another night of zero Covid cases, Associate Health Minister Ayesha Verrall says.

But she says Cabinet will want up-to-minute test results - including the remaining tests from the likes of gym members connected to the latest cluster - before making a call today as to whether alert levels can drop in Auckland and the rest of New Zealand.

"No news is good news from my end. We haven't heard anything overnight," Verrall told Newstalk ZB's Mike Hosking on Friday morning. The formal update would come through at 9am.

When asked why Auckland was still in lockdown after five days of zero cases, she said: "It's important we took all of the health advice into account at the time when we went into lockdown. Remember there was a series of high-risk exposures we had to deal with."

Asked by Hosking whether she'd take the same approach again, she said: "Doing the same thing again is not how I choose to approach things. But you have to make sure at the end of an event you get all the data and see what you can learn. My part of this is to make sure we have used the contact tracing system as well as we can. We used it differently this time; there was a lot more focus on casual contact places, various places in the community. I'd like to see if that approach helped us reduce transmission or if we can alter our approach to casual contacts."

Auckland's freedom could hang on 85 Covid test results, with Cabinet deciding this afternoon whether to lift the level 3 lockdown - and alert level 2 in the rest of New Zealand.

Those tests from casual plus contacts at the City Fitness, MIT, Kmart Botany and Papatoetoe High School exposure events are among the key indicators health chief Dr Ashley Bloomfield will be looking at before making his recommendations.

Cabinet will meet at 2pm today and Prime Minister Jacinda Ardern and the director-general of health will announce the decision at 4pm.

It bodes well there are no new cases this morning - for the fifth day in a row - despite more than 7850 tests across Auckland on Wednesday. More than 68,000 tests have been processed nationwide over the last week.

"We're pretty confident now we've got a sharp perimeter around this particular outbreak. All those things will give us confidence that there hasn't been onward transmission," Bloomfield said.

But while all the close contacts of the latest cases have all tested negative, there are 85 people who are still being chased to get a test.

Of the 185 people who were at the City Fitness gym with Case M last Friday, test results for 29 people were still being chased down yesterday.

Bloomfield said those results were key because that gym visit was the last major exposure event in the Valentine's Day outbreak.

There were also outstanding test results from two people who were at the Manukau Institute of Technology and 43 out of the 1882 people at Kmart Botany who hadn't yet been tested.

All but one of those people had been contacted and gave assurances they were being isolated while health officials "actively supported" them to get a test. The Health Ministry did not provide details of the final outstanding person in that group and whether they could be contacted.

Bloomfield said it was neither frustrating nor concerning there were still outstanding tests because it could just be a matter of laboratories matching results to people.

At Papatoetoe High School all but 11 students had been retested and eight of them were being visited by mobile testing vans yesterday.

Two of the students have refused tests and had isolation plans managed by Auckland public health officials.

Bloomfield didn't know what reasons the students gave for refusing to be tested.

"It may just be a belief system. There are a small number of people who subscribe to a belief that Covid-19 doesn't actually exist. I know that the vast majority of people don't subscribe to it.

"Or it may just be that they really, really do not want to have a test."

There was also one last student who has already tested negative twice who contact tracers couldn't get hold of to see if they'd had a third negative test.

But all the people who worked with Case J at Kmart Botany and Case L at KFC in Botany Downs have all tested negative.

"The priority for us is to ensure we have tied up all the loose ends from the college, from the testing of other casual plus contacts - for example the earlier Kmart exposure - and in particular from the MIT and the gym last week," Bloomfield said.

The other key indicators Bloomfield will be looking for is laboratory capacity to process tests which is sitting at about 25,000 a day and wide surveillance testing.

"A really important part of our advice is the wide testing setting both in Auckland and outside which will increasingly provide assurance that we haven't got onward transmission into the community.

"So those high rates of testing over the last few days have been incredibly helpful."

There were also six new cases in managed isolation yesterday and two of them were hospitalised but it was not known yesterday if their conditions were due to Covid-19.

When Cabinet meets to make its decision on whether to lift level 3 in Auckland and level 2 around the rest of Aotearoa, it first considers Bloomfield's advice alongside the latest case numbers, contact tracing, geographical distribution of the infections and whether the outbreak can be connected to the border.

The ministers then move on to assessing what effects alert levels have on the economy and society - including the impact on vulnerable populations - then finally whether changing the alert levels could be operationalised safely.

Covid-19 Response Minister Chris Hipkins said this week due to a change in the rules they could be more nimble with how quickly they can raise or lower alert levels.

Auckland is scheduled to come out of lockdown overnight on Saturday but Cabinet could opt to lift it sooner.