Epidemiologist Michael Baker says the dropping trend in daily case numbers - 96 nationally yesterday - is a positive sign that increased vaccination rates are working.
But we won't see the effects of the traffic light system potentially increasing daily cases until the end of the week or early next week, Professor Baker told the Herald.
"The settings of alert level three was working well ... I think we would expect to see cases go up with the traffic light system because there is a lot more mixing going on," he said.
However, he said the main goal of the traffic light system was to stop transmission indoors between unvaccinated people.
"Our biggest risk will be private parties with unvaccinated people which could be difficult to contain during the festive season," Baker said.
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He called on Jacinda Ardern to open the Auckland border tonight. "Release it tonight ... we don't need it."
He wanted to know how Ardern was making this decisions because there was criteria around red, orange and green settings - but it wasn't being followed.
Luxon told The AM Show that if people weren't vaccinated then they should go and get vaccinated.
On iwi involvement with police at Northland borders, there was also a lot of ambiguity around how long it would take to get through the border and how many checks would be made, he said.
It would be an extremely frustrating process for Aucklanders trying to get out of town.
Luxon told TVNZ's Breakfast that after more than 100 days in lockdown, Auckland could and should be at an even lower level in the traffic light system. He said restrictions in the city should be reduced even further.
"If Auckland can be in orange, let Auckland be in orange," he told Breakfast.
"If the director-general of health Ashley Bloomfield is telling us that we have high vaccination rates and the hospital system is not overwhelmed, then our biggest city should be in the orange light setting now as that was the criteria."
Execution and management mattered when it came to the Covid-19 response, he said - in this case, making sure there were enough ICU beds prepared in case we got to a point when they were needed.
Police Association president Chris Cahill told The AM Show officers weren't happy at being deployed from around the country to man Northland checkpoints and instead should be back in their districts doing the busy work that happens over the Christmas and New Year period such, as family harm and mental health incidents.
He didn't believe they should be stopping vehicles of people who were already vaccinated.
Overall it was 300 officers that wouldn't be in those districts to do the work that occurred there and something had to give.
Cahill hoped that after a few days the reality that they weren't stopping unvaccinated people would be proven and they would be able to shut it down.
He said at the moment it was set to go for a month which was an "absolute waste" of police resources and victims would rather see police in their own districts.
There were 96 new cases in the community yesterday, that's down from 182 last Monday, November 30.
Of those 96, 74 cases were in Auckland, 10 in Waikato, eight in Bay of Plenty, one in Taranaki and five in Nelson-Tasman.
There were also two new cases in Northland being announced, but those figures would be included in today's daily count, the Ministry of Health said in yesterday's 1pm statement.
A total of 66 people are in hospital, including seven in ICU.
In Auckland, there were 3200 people isolating at home, including the 843 Covid cases.
"There are now 20 active cases in the Nelson area. Investigations into the source of infections are ongoing," the ministry said.
Yesterday afternoon, the Herald revealed a student a St Anne's School in Manurewa has tested positive for Covid, forcing a further 25 pupils and three staff to get tested and self-isolate.
Principal Glen Ryan said students and staff went for their first test today and were awaiting their results. The students were 10 and 11-year-olds.
A Department of Conservation hut in the South Island's Fiordland National Park had been identified as a high-risk Covid exposure site.
An infected person had arrived at the hut on Saturday at 7pm and left the following morning at 8am. Everyone in the hut at the same time has been deemed a close contact.
The Ministry of Health is advising anyone who stayed overnight on Saturday in the Green Lake Hut to self-isolate and get tested immediately.
Officials regard the remote wilderness setting as a high-risk for anyone in the same venue, the latest locations of interest show.
Another Covid case was confirmed as a second staff member at Enner Glynn School in Nelson.
In a post to Facebook, principal Isaac Day said they received confirmation from the Medical Officer of Health about the new case.
The staff member is considered to have been infectious from December 4, it said.
The virus has reached several parts of the South Island with four new cases emerging in Nelson-Marlborough yesterday and two more appearing in Canterbury.
Nationwide 93 per cent of eligible Kiwis have had their first dose and 88 per cent are fully vaccinated, the ministry said yesterday.
Baker said as New Zealand headed into the festive season, his biggest concern was infected Aucklanders spreading it around the country.
"We are entering uncharted tertiary, it's unpredictable what will happen next," he said.
His message to Aucklanders was: "If you are leaving the big city for Christmas, please do everything you can not to take the virus with you.
"That means get tested, especially if you have children in your household. Try to get at least one family member tested, maybe one of your children under 12 who isn't vaccinated."
Baker said it was equally important to have a conversation now with the people you are going to be mixing with on holiday.
"Make sure they are all vaccinated, there's still time to get your first dose now and your second dose before New Years Eve."