Director-General of Health Ashley Bloomfield will give Cabinet the latest information about testing results, as well as laboratory and contact tracing capacity, ahead of its review of the COVID-19 alert levels.
Auckland is currently under alert level 3 lockdown while the rest of New Zealand is at level 2, and on Friday Cabinet ministers will meet to review the restrictions and discuss whether they should be lifted, stay in place, or be extended.
Prime Minister Jacinda Ardern will announce Cabinet's update on Friday at 1pm, but ahead of that decision Dr Bloomfield and Health Minister Chris Hipkins provided some clues on Thursday about what to expect from the outcome.
"I think a key thing is the level of testing that's being done outside of Auckland that will give us a very good picture about whether there has been spread beyond Auckland, so that will be a key piece of information for Cabinet," Dr Bloomfield said.
"The way I think about it is the extent to which we're confident we have found the boundaries of the current outbreak and in a sense through our contact tracing being able to draw the net tightly around it. Those are critical pieces of information.
"The other piece of information that we have to report to Cabinet is: are we confident in our lab capacity and our contact tracing capacity? Both of those are in good shape and that will be helpful."
The Ministry of Health reported five new confirmed cases of COVID-19 in the community on Thursday, but they are all connected to the original south Auckland cluster that sparked the city's level 3 lockdown last week.
On Wednesday it was revealed a maintenance worker at the Rydges Hotel managed isolation facility had tested positive for the virus, and he is not part of the original cluster, but so far it appears he has not passed it on to anyone else.
Health officials have been able to trace the man's strain of the virus to a returnee from the US, and Dr Bloomfield said evidence has shown they both used the same elevator which could be how the man picked up the virus.
Hipkins said Cabinet will examine how the virus has spread ahead of the alert level decision.
"Obviously we'll be looking at the latest information on this cluster, what we know about the cluster [and] what we know about the contact tracing that's happened around the cluster," he said on Thursday.
"We'll be looking at the test results from the surge of testing we've done across the community and the surge of testing we've done around the border and around managed isolation."
Hipkins said more than 18,000 tests were processed by laboratories on Wednesday, while more than 23,000 were completed the day before.
"We'd be looking at any cases that aren't connected and we've identified obviously one so far and so we'd be looking at are there any further that we can't identify a clear link."
Since August 11, the Ministry of Health has identified 1983 close contacts of people who have tested positive for COVID-19. More than 1860 of those people have been self-isolating, and the rest are still being contacted.
"We'd be looking at whether any new cases are within the existing contacts, so people who have already been contacted, or are there new cases coming up, and if they're linked to a cluster, were they people we didn't know about previously?" Hipkins said.
As for whether Cabinet could announce an easing of restrictions on Friday, Hipkins said the question is a "hypothetical" and that ministers will need all of the most recent information to make an informed decision.
"Ultimately, we'll see what more advice comes in overnight before I'm in a position to make any comment on that," Hipkins said. "We do, when we make those decisions, rely on information right up to the hour before we sit down as a Cabinet."
Prime Minister Jacinda Ardern on Wednesday ruled out a move to alert level 4 and said the edge of the Auckland cluster is near, which is "encouraging".
"We're seeing the perimeter of the cluster," she said. "A way to go yet, but there are early signs of the management of this cluster."
Newshub's political editor Tova O'Brien reported that if wider New Zealand does move down to alert level 1, Auckland could expect to be at level 2 for a couple of weeks before returning to a new normal.
The current alert levels have been set until Wednesday, August 26, unless the Government decides to lift the restrictions earlier.