There are 12 new cases of Covid-19 in New Zealand today, all in managed isolation.

Director of Public Health Dr Caroline McElnay says all the new cases have been transferred to a dedicated quarantine facility.

There are no new cases in the community.

Dr McElnay says 10 of the cases came from India on 26 September on flight AI1354, they were sitting between rows 14 and 41, so spread out on their journey.

One case arrived from the US on 26 September and tested positive on day three, the other person came to New Zealand from Philippines via Taiwan.

There is one person in Middlemore Hospital in the general ward on isolation.

Dr McElnay says 4047 close contacts of cases have been identified, all have been contacted. The number drops from yesterday as there were duplicates.

Three cases have recovered. There are 1492 total confirmed cases.

There were 5679 Covid-19 tests processed yesterday.

There are now over two million people registered on the Covid Tracer app.

"It is important to stay vigilant this school holidays, continue to use the app or write down where you have been. Seek advice if you are unwell and wash your hands," says McElnay.

The higher number of 12 people who have tested positive reflects the fact that flights are coming from places with a higher level of Covid-19.

"That's what our border control systems are designed to do."

McElnay says the assumption is that anyone coming into New Zealand may be infectious and every step of the process reflects this.

She says genomic testing is being done for all the cases coming into New Zealand, helping them work out a chain of transmission.

"Our most likely theory is that these are individuals that were infected in India before the flight."

There have been previous occasions where flights have brought in a number of cases, she says.

The crew on the flight, were transported to managed isolation when they arrived but have since left the country.

Anytime a case is picked up overseas, the assumption is that they could have been infectious while they were in New Zealand and close contacts are followed up.

The August cluster is not yet officially closed, says McElnay.

"It's really a time-based process, we look at the date of the last case ... it's a 28-day period after the last case that was reported has recovered."

She says it would be at least another 28 days before it can be closed at this point.

A number of rapid tests have been developed across the world but they are not all as accurate as the testing we currently have, says McElnay.

She says the plans for a resurgence or outbreak is being constantly reviewed.

"The challenges that comes with summer are also kept in mind."

Yesterday, one new case of Covid-19 was reported, of a person in managed isolation who had arrived from France via Singapore on 25 September.

Meanwhile, some students are urging the University of Auckland to hold online exams at the end of the year, saying a shift to on-campus assessment would be disruptive after learning remotely for so long this semester.

The university has been teaching students online since Auckland went into a level 3 lockdown and planned to resume regular lectures late next week if the city moved to alert level 1.

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