As cases mount in Australia and it abandons its long-held COVID-19 elimination policy, New Zealand is sticking firm to the same goal, insisting it remains possible.

New Zealand had 41 new community cases on Tuesday, another growth after 35 on Monday and 21 on both Sunday and Saturday.

Officials hope the 41 new cases is near the peak of the outbreak, given it is day seven of a national lockdown, and those restrictions are expected to curb case numbers around day eight to 10.

Prime Minister Jacinda Ardern said jump “wasn’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 are from Auckland and three are from Wellington.

Eight require hospital-level care.

The infectious nature of the Delta variant has pushed New Zealand’s contact tracing regime to the brink.

There are more than 400 potential exposure sites which have generated 13,230 contacts.

Those contacts all need to be followed up, isolated and tested – but under-resourcing in New Zealand’s health system means almost half have had no contact from contact tracers.

This is a key reason for the lockdown: To keep Kiwis at home and to 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 NSW and Victoria, where it just climbs relentlessly.”

Ms Ardern said she wouldn’t budge 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 said.

“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.

“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.”

-AAP