COVID-19 graph predicts New Zealand would have had 550 daily cases if not for lockdown

The Prime Minister says New Zealand's alert level 4 restrictions are "making a difference" to our COVID-19 numbers, suggesting daily cases may have been ten times higher on Monday if not for the lockdown.

At a press conference in which she also announced most of the country would be shifting down an alert level this week, Jacinda Ardern said modelling had shown lockdown had prevented us seeing what could've been as many as 550 cases a day by now.

She held up a graph, created by disease modelling experts, that suggests daily case numbers would have been "literally off the charts" by now.

"The sacrifice everyone is making is extremely important and is making a difference," she said.

"Yesterday, I received this graph. The red line shows what would've happened if we hadn't moved hard and fast into level 4. It tells us that the daily case numbers are literally off the charts.

"Without level 4, some modellers estimate that the number of new cases today could have been around 550."

The graph shows just how bad our case numbers could've been if not for lockdown.
The graph shows just how bad our case numbers could've been if not for lockdown. Photo credit: Prime Minister's Office / Supplied

The lines underneath the red line showed the scenarios New Zealand could still follow - though Ardern admitted it was still all up in the air for now.

"At the moment, we're tracking roughly in the middle of those options, and where finally will land and when we'll land there is not yet clear."

But that doesn't mean we're powerless, the Prime Minister said.

"The more we do to limit our contact, the faster we exit these restrictions. And more importantly still, the more lives we save," she told reporters.

"You'll have heard today Dr Bloomfield mention the number of people in hospital. It is a number that, each day it is reported to me, reminds me how serious this illness is."

Earlier in the press conference, Ardern confirmed Auckland would remain at COVID-19 alert level 4 for another two weeks, starting at 11:59pm on Tuesday, with the settings being reviewed again on September 13.

She says Cabinet needs to be confident Delta isn't circulating undetected in the community.

Ardern says additional wastewater testing is due from Northland on Thursday, so Cabinet wants to wait for those results before shifting alert levels there. If the results come back negative, Northland could move to level 3 at 11:59pm Thursday.

Meanwhile, every other region in New Zealand will move to alert level 3 from 11:59pm on Tuesday, as announced last week. Business owners are now able to enter their premises to get ready for this change.