Covid-19 Response Minister Chris Hipkins says there are two new cases in the community, as Cabinet prepares to decide whether to extend Auckland's lockdown.
Hipkins said both were students at Papatoetoe High School.
More than 15,000 swabs were still to be processed as of last night and today's test results will be key to knowing whether the outbreak has been contained.
However, the government still has no evidence of how the infectious UK variant B.1.1.7 made its way in to the country.
Cabinet meets to to decide this afternoon whether Auckland will move out of level 3 lockdown, and the Prime Minister will announce the decision at 4.30pm.
Read more on the latest Covid-19 outbreak:
- RNZ's live blog for the latest Covid-19 updates
- Covid-19: What happened in New Zealand on 16 February
- View updated locations of interest here
- Alert Level 2 and Level 3: What they mean
No new community cases were recorded on Monday or Tuesday.
Earlier Hipkins told Morning Report he hadn't been informed of any more cases overnight which was "probably a good sign".
"No evidence of community spread so far, and that's a really positive sign. We've managed to identify and isolate and test close contacts for the three cases and again that's a good sign, it means that we can contain any spread from there.
"So far their results are coming back negative, which suggests that if they have passed the virus on it won't have spread any further because we've managed to isolate their close contacts.
"Even if they do subsequently get it, the odds of them spreading it to anyone else are very, very low."
Hipkins said the outbreak was taking a different course than the Auckland August cold store cluster, which led to a two-and-a-half week lockdown.
In testing after that outbreak, cases came to light within a day or two, but there hadn't been anything similar this time, he said.
"Those are good contributors to Cabinet's decision this afternoon, he said.
"There are still some question marks that we'll want to have as much information around as we can, including more information on the source investigation."
There are a variety of "highly unlikely scenarios" that the government is looking at to determine how these cases happened "and it has to be one of the highly unlikely scenarios".
The possibility the virus came through LSG Sky Chefs laundry could not be discounted, though transmission from soft surfaces such as blankets is highly unlikely, he said.
One of Auckland's three community works in the laundry area of LSG Sky Chefs, her daughter is a student at Papatoetoe High School and third case, the father, a self-employed tradesman.
Hipkins said with the daughter being the first to show symptoms, the possibility she caught it through community transmission was being explored, though that was also improbable.
"In the case of the cold store, we were never able to absolutely identify how it made into the cold store and how employees got infected. That's one of the frustrations about this virus."
Hipkins said the government is considering whether border workers at the airport who don't come into contact with passengers should be tested weekly rather than fortnightly.
"The laundry workers have not been on a mandatory testing cycle. We'll be looking at whether they should be added to the testing cycle."
Saliva testing has been rolled out first at high risk locations such as the Jet Park quarantine facility, as its effectiveness is checked.
On the use of the the Covid Tracer app, Hipkins said he was looking at ways of keeping the number of scans up and would be announcing decisions in the next few days.
This is an official government Covid-19 announcement:
Auckland is now at alert level 3, the rest of the country is now at alert level 2. Cases of Covid-19 have been identified in the Auckland community. Restrictions will remain until Wednesday at midnight. A further announcement on next steps will be made at 4.30pm this afternoon. Travelling in or out of Auckland is restricted. Stay home, stop the spread. For more information on the alert levels go to covid19.govt.nz
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