There have been 13 days in a row of no new Covid-19 cases and director-general of health Ashley Bloomfield says New Zealand is the envy of many other countries.
There is still one active coronavirus case, Bloomfield said in his daily update.
He did not have any details on the one active case - they would be declared recovered at least 10 days after the onset of symptoms and 48 hours after their symptoms ended.
"It may well be that the person is at the tail end of that 10 days."
He said it was "satisfying" for New Zealand to be in its current position - which was "better than we might have anticipated" thanks to how well people followed the lockdown rules
Nearly 2650 Covid-19 tests were completed yesterday, bringing the total to 286,174 since the pandemic began.
There were another 8000 registrations on the NZ Covid Tracer app yesterday. Bloomfield said it would still be important and useful in level 1 and people were encouraged to keep using it.
Businesses which were still not contact tracing should "get with the programme", he said.
Authorities were looking at making it an official requirement in level 1, which the country may move to as early as next week.
But "we cannot afford to take our eye off the ball here".
Kiwis' hard work and sacrifice - has it paid off?
New Zealand is in a privileged and hard-won state with Covid-19 but internationally it's a different story - the highest number of cases globally in one day was just three days ago, on June 1.
There have been around 380,000 deaths reported to the World Health Organisation.
"We are still very early in the evolution of this pandemic," he said. "There are still many gaps in our knowledge."
New Zealand is the envy of many countries, he said.
That's due to the hard work and sacrifice of New Zealanders - but the country could not afford to act as if it was "all over globally" when really it had just started, Bloomfield said.
Italy has just started lifting restrictions - despite having more than 40,000 active cases and 3000 new cases in the last week.
In New South Wales, Australia, rates of cases were very low, with no new cases yesterday - but 13 confirmed cases in the week to May 30.
NSW's confirmed cases were around double New Zealand's number of both confirmed and probable cases. The state's population was similar to New Zealand and Bloomfield said it was a good comparison.
Both NSW and New Zealand had substantially lower death rates per case than other countries.
Restrictions were being lifted comparatively quickly in New Zealand - including compared to NSW.
On Monday, Bloomfield joined a regional WHO call on the topic of how to reopen borders safely.
"We need to remain vigilant to the threat that the virus poses," he said. While NZ was looking at a possible return to level 1, this would not be life back to normal. Hand hygiene, keeping a diary of where you've been and staying home when sick were all important.
Despite New Zealand being ahead of other countries in the Covid-19 fight, Bloomfield said there were still lessons to be learnt from other countries as they reopened borders and lifted restrictions - including Italy and the UK.
"For example, if they get a second wave of infection, how quickly that happens and what measures they take to contain that second wave."
It would also be useful to see how countries fared due to seasonal changes - for example in Italy which was now in summer, as opposed to when the initial outbreak happened, Bloomfield said.
A "belt and braces" approach was being taken at the border because new chains of transmission sneaking into the country would mean restrictions on the economy.
Asked whether there was a "plan B", Bloomfield said he hadn't seen a better plan than what New Zealand already had - which included prevention of cases coming in, and containment through measures like rapid testing and quick contact tracing.
Once a decision about a transtasman bubble had been made, the process would be thoroughly tested at airports on both sides to ensure both countries were happy that all the right measures were in place.
He hoped all businesses would download a QR code for the Covid Tracer app. He did not give specific consequences for those which did not contact trace - but said slowing down that process could mean restrictions on all businesses, which he hoped would be a deterrent.
Regarding asymptomatic transmission, Bloomfield said there was mixed evidence that people with no obvious symptoms could be infectious. But others may be at the tail end of infection and might test positive despite having no symptoms. He said evidence suggested those people were not infectious.
Transmission in indoor settings such as workplaces was common, whereas outdoors the virus was less likely to transmit, Bloomfield said. That was partly because of weather conditions but also because people tended to stand further apart outdoors.
NZ health system 'returning to normal'
Healthcare services are increasingly returning to normal, Bloomfield said - reminding people that the bowel screening programme is "well up and running again". Around 29000 people had received testing kits before the lockdown and were asked to wait till restrictions lifted before returning them. Some 11000 of those people had now sent in their tests.
Immunocompromised children can return to school in alert level 1, Bloomfield said, and vulnerable adults can get about their daily lives.
If the trend of zero new cases continues, New Zealand is likely to move down to alert level 1 next week. Cabinet will make a call on Monday,with the loosening of restrictions possible just 48 hours later.
Prime Minister Jacinda Ardern yesterday outlined the "10 golden rules of level 1", which showed apart from a heightened awareness of hygiene and ongoing border controls, life will be almost back to normal.
However, just one case of untraceable community transmission could keep New Zealand in level 2.
Ardern had initially signalled June 22 was the day when Cabinet would decide whether to move to level 1, with the possibility of doing so earlier.
She's now brought the date forward following advice from Bloomfield that numbers were better than expected.
But there are calls for the move to be made immediately, following the leak of a Cabinet paper which showed there had already been more than 28 days without known community transmission.
Once that milestone had been achieved, "and we have confidence in our border controls, there is theoretically no need for restrictions on people's movements, interactions or activities", the advice to Cabinet said.
National Party leader Todd Muller quoted the leaked paper in Question Time yesterday, arguing the country should already be in level 1. Every day at level 2 allowed businesses to sink further, he said.
But Ardern argued that an earlier move to level 1 would not have given sufficient confidence that community transmission was not occurring, given the virus' incubation period was up to 14 days.
"It's only been 13 days since bars reopened and five days since gathering sizes were lifted to 100."