Two more people have tested positive for Covid-19 and there are now 10 active cases in the country.

Both of the two new cases are in managed isolation facilities, director general of health Ashley Bloomfield says.

The first is a man in his 20s who arrived from India on June 19 and has been staying at the Pullman Hotel and has been moved to quarantine at the Jetpark Hotel.

The other man is also in his 20s and arrived in New Zealand on June 18 from Los Angeles. Due to a mix-up, he'd been staying in quarantine at the Jetpark Hotel since arriving.

The traveller from India flew in on Air India flight AI1316. He has been in managed isolation at the Pullman Hotel. He has been transferred to the Jet Park Hotel.

The man who arrived from the United States arrived on flight NZ5 from Los Angeles.

10 active cases

Another case has now recovered so the number of active cases is 10.

More than 4300 tests were done yesterday.

Homeless person staying in isolation centre

The ministry hasn't been able to verify a rumour about a homeless person who spent two weeks in managed isolation.

"As far as we can tell this can not be verified and might be an urban myth, sorry to disappoint you," Bloomfield said.

Testing Kiwis in isolation facilities

Fifty-five people have left on compassionate exemptions since June 10 and all have now been followed up and tested. Some of these had been tested before departure.

He said 190 people staying at the Novotel Ellerslie with the two women and five people were yet to be followed up with.

The Ministry was working to contact 2,159 people who've left isolation since that date.

Bloomfield said they'd all been screened upon departure and were being followed up "as a final precaution".

If they hadn't had a text or call, Bloomfield urged those people to call Healthline.

Bloomfield said New Zealand was one of very few countries which requires both 14 day isolation and double-testing before being allowed in the community. He said this was in line with international health guidelines.

The 2,159 people who'd left isolation without tests posed "a very, very low risk" to the community because they'd completed the 14 days of isolation, said Bloomfield

Ninety-nine per cent of people who show symptoms do so by day 12, so the 14 days had room built into it, said Bloomfield.

Bloomfield conceded that in addition to the 35 imported cases reported before June 9, there may have been people who were asymptomatic in isolation but their case was not caught and reported.

But they didn't pose a high risk to the community because the isolation period covered the incubation period of the virus.

"The 14 days served its purpose."

Bloomfield said "we were celebrating zeros" because New Zealand was lauding not having Covid-19 in the community.

The struggle to track down how many people hadn't been tested was because it required matching people's National Health Index (NHI) number with data from the border facilities which didn't previously record NHI numbers, Bloomfield said.

"I wish it was easier [to get the data] and this is one of the key challenges of the healthcare systems."

Bloomfield said "there's no obstruction" about getting the data and there was a team working on following up the compassionate leave people with urgency.

Bloomfield couldn't say how many people had left isolation and had been tested.

The people who'd left isolation without being tested didn't pose a concern to the community, he said.

"I will get you that number and I'm sorry I haven't got it."

Bloomfield said not collecting an NHI at the border "wasn't an oversight" and happened because some people hadn't lived in New Zealand for sometime so either didn't have one or it was difficult to locate.

Visits to two Covid-positive sisters

Bloomfield said the person who visited the two Covid-19 positive sisters followed the rules and stayed at a distance.

The local medical officer of health deemed there wasn't a risk but the person was tested anyway which came back negative. The person decided to also self-isolate as a precaution.

Why Kiwis aren't tested at the border

Bloomfield said there'd been suggestions about testing people upon arrival into the country, which would be a third test as well as those on day three and day 12.

Testing on day three was more likely to pick up an infection rather than testing on arrival.

Since testing has ramped up at isolation facilities, more cases have emerged in the past week.

But for a period of 37 days, there were no imported cases. Bloomfield yesterday put this down to an increase in the number of people returning to New Zealand and the acceleration of the pandemic overseas.

Otago University epidemiologist Professor Michael Baker said a third factor was that, before the test-all policy came in, some positive cases may never have been picked up.

The Ministry of Health has been repeatedly asked how many of the 55 people granted a compassionate exemption left isolation without being tested between June 9, when strict testing measures were introduced, and June 16.

But the ministry has been unable to answer.

The questions were prompted last Tuesday when it was revealed that two sisters were allowed to leave managed isolation on compassionate grounds without being tested, and subsequently tested positive.

Health Minister David Clark is also due to release a new testing strategy today for the general population as the number of Covid-19 cases in arrivals increases to nine.