A Covid-19 case that has yet to be epidemiologically linked to the Auckland cluster means there still "could be other people we are missing" Prime Minister Jacinda Ardern says.
Ardern says the case was picked up just before the country moved to Alert Level 2.
"This is a case that while it has been genomically linked we have not yet been able to determine the person to person link to our cluster," she said.
"That means there could be other people we are missing.
"That has happened to us before and it doesn’t mean we can’t contain the outbreak around them successfully.
"But it does give us reason to be careful and cautious."
Her warning comes after a man in his 30s arrived at North Shore Hospital on Friday August 21 feeling ill and then tested positive for Covid-19.
His case raised flags as it could not be epidemiologically linked to the cluster but could be traced via a genome link to the outbreak.
Today Ardern announced Auckland will remain at Alert Level 2.5 for the time being, with a review taking place in 10 days' time on September 14.
The rest of the country will stay at Alert Level 2.
Cabinet met today to review the current alert levels, with Ardern saying health advice and the amount of time Auckland had been at Level 2.5 was among what they considered.
"Going on just five days at these new settings, we don't yet know the impact of our level shift of Auckland and beyond," she said.
"It is simply too early to know just now."
She also said early modelling showed the greatest period of risk was over weekends.
“Lockdown must always be at our last resort. The best economic response remains a strong health response,” Ardern said.
“That means looking at what the health evidence tells us.”
“At this stage the Auckland cluster remains contained,” Ardern said, adding there was no indication that Auckland needed to raise its alert level.
Director-General of Health Ashley Bloomfield said there were three more cases of coronavirus in the community, all linked the August Auckland cluster, and two in managed isolation.
Ardern said since Auckland had been at Level 2.5, there had been “another 30 community cases all associated with the cluster and people identified as close contacts and already in isolation”.
“Everyone has taken the most recent setting seriously, too.”
However, she added that "staying on track to lift restrictions with confidence does mean taking a cautious approach now".
Auckland moved to Alert Level 2.5 last Sunday, after being at Alert Level 3 and the rest of New Zealand has remained at Level 2 since August 12.
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