The Delta outbreak has also sent TV presenter Hilary Barry and 1000 others into isolation after a Mitre 10 gala awards dinner in Auckland attended by another positive case.
As New Zealand starts lockdown weekend, with 28 confirmed cases in Auckland and three in Wellington, students at the University of Auckland and Auckland's De la Salle College and McAuley High School have tested positive - and attended classes while infectious.
Deputy Prime Minister Grant Robertson said this morning he hadn't been given an overnight update on the latest numbers but "there will be more cases".
"We will see more cases, in part because of the extraordinary uptake of testing. There will be more cases," he told Newshub Nation. "We just have to expect that things get worse before they get better".
He said he was aware of more than 40,000 tests undertaken across the country yesterday.
A three-day lockdown began at 11.59pm on Tuesday August 17,, after an Auckland man tested positive for the Delta variant of Covid-19. He had also travelled to Coromandel while infected. Initially the lockdown was for three days nationwide, except Auckland and Coromandel which was to be in place for at least seven days.
However, Prime Minister Jacinda Ardern announced on Friday that lockdown had been extended nationwide until 11.59pm on Tuesday, after confirmation the Delta outbreak had spread to Wellington.
It comes as 11 cases, including three in Wellington, were announced on Friday, taking the total reported in the community since Tuesday to 31.
The three in Wellington had travelled to Auckland on Sunday - one by plane and the others by car - after visiting a location of interest there. The remaining eight cases were in Auckland.
Nineteen cases are now confirmed as part of the Auckland outbreak, with the remaining 12 under investigation but likely linked to the outbreak.
One person at the Mitre 10 dinner - held at Auckland's Spark Arena during alert level 1 on August 12 - is understood to be infected with Covid-19. In a statement, Mitre 10 said it has been told the dinner is now a location of interest.
People from throughout the country attended the event which was held when the country was still at alert level 1. One of those was Seven Sharp co-host Hilary Barry, who said on Twitter she was now in isolation for two weeks.
As well as details of the new cases, the Delta outbreak has seen thousands of Kiwis rally to get tested nationwide.
Robertson said as soon as there was a positive test result, authorities were working immediately to locate close contacts and get in touch with businesses which were locations of interest.
He refused to confirm Auckland's lockdown would likely extend beyond Tuesday - amid criticism from businesses that the Government should have confirmed that yesterday - saying the Government wanted to see all of the data and information from the weekend, before Cabinet met on Monday.
He also defended the delay in the Government releasing locations of interest, saying it was important accurate information was released, and businesses were made aware they were locations of interest before the public.
Govt has failed massively over vaccinations - Collins
National leader Judith Collins said lockdown was the right call given the country's low vaccination rate, and given there was no certainty on the source of the "border failure".
She suspected a lockdown longer than a week in Auckland, and said the Government needed to provide people with more certainty on the length of the lockdown.
She criticised the vaccinations schedule, saying they had "failed massively. The Government had one job this year."
Collins said it was "simply unacceptable" to have nurses in hospitals unvaccinated, and there needed to be clear targets set for vaccination.
Students infected
Students at the University of Auckland and Auckland's De la Salle College and McAuley High School have tested positive - and attended classes while infectious.
An email to staff last night from the University's vice-chancellor, Dawn Freshwater, said the student - a resident at Whitaker Block - attended classes on Monday and Tuesday this week.
The student then travelled to Wellington to be with family before testing positive, Freshwater said.
"The university is working closely with the relevant health agencies on this situation, and is following their protocols, including for contact-tracing, to support our student and to protect the wider university community," Freshwater said.
Residents in the university's Whitaker Block were warned about the positive case.
"We know this may cause concern and be distressing. The university will be in contact with you as soon as we have more information. In the meantime, please try and get a good night's sleep," a letter to residents said.
Parents and caregivers of Auckland's De la Salle College and McAuley High School were also advised by letter of the news of the positive cases.
McAuley, in Ōtāhuhu, has roll of close to 800 and the student attended class while infectious on August 17. De la Salle, in Māngere East, has a roll of close to 1000. One of its students also attended the school on August 17 while infectious.
"Aside from visiting a testing facility, you will need to stay at home and self-isolate in case you become ill with Covid-19. It is important to watch for symptoms of Covid-19 ... while in self-isolation. Any household members you live with will also need to self-isolate until you return a negative Day 5 test result," the letters to parents said.
Hilary Barry isolating
Barry last week MC-ed the Mitre 10 2021 Awards ceremony at Auckland's Spark Arena, in downtown Auckland.
One of the event's bar workers has since tested positive for Covid-19.
Barry revealed live on Seven Sharp last night that she, like all others at the event, were being treated as close contacts, and had to be tested and self-isolate.
"Every single person at that event is considered a close contact," Barry said.
She said she felt "fine ... a box of birds".
Barry said she arrived at TVNZ on Friday night before being told that someone at the event had since tested positive.
