Director general of health Dr Ashley Bloomfield says New Zealand is still on track for a move to level 2, with no cases of recent community transmission and a vast improvement in contact tracing.
He added that masks will not be compulsory at level 2 and, while physical distancing will be more important than ever, people should be able to give their friends and family a "quick hug".
From April 18 to 20, it had taken 10 days to isolate 80 per cent of close contacts from the first onset of symptoms from the source of a Covid-19 chain of transmission (the index case).
Today that has been halved to five days, and Bloomfield said the Ministry of Health wanted to shave it to four days in line with a benchmark in the system audit by infectious diseases specialist Dr Ayesha Verrall.
"I think that's very promising," Bloomfield said of the improvement.
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The latest data published by the Ministry of Health shows:
• 80 per cent of close contacts are being isolated within two days of a positive lab result.
• 70 per cent of people are being tested within 48 hours of their first symptom.
• 70 per cent of test results are returned within 24 hours of a swab.
These measures are for 270 contacts for 75 cases over the last two weeks of level 4 lockdown - April 13 to 27.
Bloomfield had met Verrall at the weekend to assess the system's improvements and he said he would publish her letter tomorrow - but he said Verrall was, "broadly speaking, very comfortable with progress".
No recent community transmission cases
Cabinet will decide on Monday whether to move down from alert level 3, and Bloomfield said the most recent data was critical before he provided advice.
But he said the signs were looking good and there was still no indication of widespread community transmission.
There remained only three Covid-19 cases of higher concern where the source of infection was unclear - and they all seemed to have been infected several weeks ago.
One was a person who flew to Nelson from the Cook Islands in late March, one was a Ministry for Primary Industries worker at Auckland airport who had been overseas prior to lockdown, and one was in Auckland who had symptoms more than a month ago.
"Studies suggest these people aren't infectious, but of course you take the same precautions," Bloomfield said.
Targeted testing around the cases, including family and workplaces, had all come back negative, he added.
"We are where we want to be. Even if we think about the [public health] advice from level 4 to level 3, we wanted to be very confident there wasn't undetected community transmission.
"We were quite confident [at the end of level 4] and that has continued through alert level 3.
"If we get a similar result today and tomorrow, I think that's a very reassuring picture."
Bloomfield has previously referred to cases since the start of April - including in Tauranga, Te Puke, Timaru and Whanganui - where the source of infection was a mystery.
Some of them remained unresolved in terms of pinpointing the index case, but Bloomfield said they were no longer considered high risk because they hadn't infected others.
"We may never know where exactly the people got their infection from, but there's been wide testing around them.
"The use of testing of asymptomatic contacts and close and casual contacts has provided us with reassurance. There's been no one with transmission, which is really what we're looking for."
A quick hug with your mates at level 2
Prime Minister Jacinda Ardern will outline today what life under level 2 will look like, and Bloomfield said the health principles were the same: physical distancing, hand hygiene, getting tested early for any symptoms, and staying home if sick.
"Hugs and handshakes - if you don't know someone, be really rigorous around physical distancing. But if it's close friends and family, you want to be careful of course, but it's starting to return to normal.
"I would imagine it would still be elbow bumps and quick hugs."
Physical distancing was more important because people will be interacting a lot more with friends as well as strangers, he said.
"We need to maintain real vigilance around physical distancing, particularly in situations where it's not quite as controlled like a work environment or a school environment."
In those higher-risk environments, such as public transport, he said people may wish to wear a mask, but they will not be compelled to.
"We've just had another look at the evidence. People may wish to use a mask. If they know how to use it properly, that's fine, but at this point we won't be insisting on masking."
Some public health experts including Otago University epidiologist Professor Michael Baker have been calling for mass masking to be considered.
Bloomfield said it was common for people in South East Asia to wear masks in public, but that was because they had a cold and were trying to prevent germs from spreading.
"One of our key public health principles is: don't go out if you've got a cold, don't go to work, don't send children to school if they have a respiratory infection."
He said that he expected testing to be ramped up again from next week, once DHBs had finalised surveillance plans.
Daily testing has fallen from a peak of 6961 on April 23, which was partly due to the lull over Anzac weekend. It has been under 5000 for the past four days.
"We want to keep the testing rates up."
Bloomfield said there had only been one reversal so far of the 24 requests to see a dying relative.
Renee West was thrilled last night to be told she could leave managed self-isolation to see her dying mother.