Auckland's border needs to remain in place for several months and some of the high-risk suburbs put under tight control should the city's alert level shift down next week, according to a leading health expert.
Otago University public health professor Nick Wilson believes the country's elimination strategy which is currently hanging in the balance still has a chance providing the Government ramps ups it efforts and starts doing mass door-to-door saliva testing and increasing the number of waste water tests it does.
But if it doesn't succeed, he said Auckland's border should stay in place to allow for vaccination rates to increase around the country.
It comes as the number of Covid-19 cases in Auckland has still been hitting double digits in recent days and many of those people have been in the community while infectious, sparking some concerns it could result in a further spike in cases.
More than half of the weekend's cases were out and about while infectious. Today five of the eight cases could have spread it while out in the community.
Where to get a vaccination in Auckland - without a booking
While it's not unusual for Covid-positive people to be out in the community - there are concerns that some of the exposure events may have happened in level 3, when there is a higher possibility of spreading the virus.
Experts say it will still be several more days whether the looser restrictions are leading to rising infections, due to the lag between exposure to the virus and developing symptoms.
However Wilson, speaking from a public health perspective, said both the mystery cases and the number of people being in the community while contagious as evident by the growing number of locations of interest were a real concern.
While some people may have caught it while following the rules, there had also been plenty of rule-breaking in a range of areas in Auckland.
Wilson believed the virus could still be eliminated, but to do so New Zealand needed to do more and use every tool in the toolbox, including requiring factory and office workers to wear masks, addressing ventilation and introducing rapid antigen testing in some workplaces.
He also wanted the Government to target the high-risk suburbs where there were persisting cases by carrying out door-to-door saliva testing, as well as intensifying its wastewater testing.
If Auckland couldn't beat the outbreak, then he argued there was good reason to keep Auckland's borders in place for at least a few months to continue to protect the rest of the country while it achieved high vaccination rate and rolled the vaccine out to 5-11-year-olds. He also believed booster shots should be offered to older and higher risk people to Auckland first and then the rest of the country.
Auckland could then possibly move to level 2 with the exception of the suburbs that were hot spots which should remain in level 3.
It would be "very sensible" to contain the virus in Auckland to avoid having ICUs overloaded throughout the country and those specialist staff could then be relocated to Auckland to help it out, he said.
Covid-19 modelling expert professor Michael Plank said based on the current case numbers he did not think Auckland was ready to move to level 2 while there were still new and infectious cases in the community.
Plank said there was a "high chance" of more people getting Covid if Auckland moved to level 2 right now and could see itself in a similar situation to Victoria and New South Wales.
If Auckland's border opened while the outbreak was growing, then it would only be a "matter of time" for Covid to spread across the country and sparked new outbreaks all over, he said.
"It is early days (in level 3), but based on what we can see at the moment the outbreak isn't quite under control still."
The Government is reviewing Auckland's level 3 setting next Monday with a likely decision that afternoon.