New Zealand has vowed to stand by its COVID-19 elimination strategy, insisting it remains possible, even as cases mount in Australia.
New Zealand recorded 41 new cases on Tuesday, another growth after 35 on Monday and 21 on both Sunday and Saturday.
Officials will be hoping the 41 new infections is near the peak of the outbreak, given it is day seven of a national lockdown, and those restrictions will be expected to curb case numbers around day eight to 10.
Prime Minister Jacinda Ardern said the current case numbers weren't unexpected.
"Where we are right now, only seven days in, we are not at the point where we are picking up infections that have been only in lockdown," she told Radio NZ.
Of the new cases announced on Tuesday, 38 were from Auckland and three were from Wellington. Eight have required hospital-level care.
The infectious nature of the Delta variant has pushed New Zealand's contact tracing regime to the brink.
More than 400 potential exposure sites have generated 13,230 contacts.
Those contacts will all need to be followed up, isolated and tested but under-resourcing in New Zealand's health system will mean almost half have had no contact from contact tracers.
It's hoped the lockdown will keep Kiwis at home and stop the spread of the virus while allowing contact tracers time to catch up.
COVID-19 modeller and government adviser Rodney Jones said continued growth of cases would challenge the government's elimination strategy.
"Containment policies may be less effective particularly if it gets into communities that provide essential workers. And that's the worry right now in Auckland," he told Radio NZ.
Mr Jones said New Zealand could follow one of three paths.
"The good path where we get a smaller number today and we slowly decline," he said.
"Or you get a little bit stuck you still producing those 15 to 20 cases a day so it's contained but you're not on the path back to zero."
"Or it's like New South Wales and Victoria, where it just climbs relentlessly," he said.
Ms Ardern said she won't be budged from her elimination strategy until vaccination rates were higher.
"An elimination strategy has worked for New Zealand before," she said.
"That's the way that we have managed to have a larger number of days without restrictions not had our people gravely ill and hospitalised and unfortunately losing their lives."
University of Otago epidemiologist David Murdoch agreed elimination was still possible.
"Absolutely we can get back to zero. It's too early to say that the horse has bolted," he told AAP.
"We had one of the strictest lockdowns globally, instituted when there was only one known case. That swift action, we don't see that much around the world."
Cars queue at a testing site in Christchurch Source: Getty
"It gives us our best chance to get on top of it. Over the last few days, we've a record both in terms of numbers of testing and the number of vaccines given out in a day."
"There's a really good chance we will get on top of this."
Dr Murdoch said another elimination of the virus from Kiwi shores should be celebrated.
"It would be a major achievement but it absolutely cannot happen without a national effort and, helpfully, the level of (lockdown) acceptance is high," he said.
"There's not actually a lot of pushback. People accept this is what we need to do."
