Professor Shaun Hendy, who is working with the Government around modelling the Covid-19 cases, has warned that yesterday's zero new cases is good, but reflects Level 4, not our current Level 3 lockdown.
Speaking to TVNZ 1's Breakfast, Professor Hendy said it was "really encouraging" to see no new cases of Covid-19 reported in New Zealand yesterday, but also said that fewer tests were typically carried out over weekends, which could be a factor.
Professor Hendy is the director of the University of Auckland’s Centre of Research Excellence in Complex Systems and Data Analytics.
He said that because Covid-19 has an incubation period, the cases we are seeing today are typically from conditions a week ago - as in, before New Zealand dropped to Level 3.
"We're only just now starting to see numbers that will tell us about how effectively Level 3 is going to be," he said.
"If we relax too much, if we do head to the beaches, if we do head to those parties - that just dramatically increases the risks.
"If we've just got those handful of cases out there - and modelling suggests there might still be a few unknown cases out there - once we burst our bubbles those cases can start spreading again.
"So it does make me a little bit nervous."
Professor Hendy said he and his team will be doing updated modelling work right up until Cabinet meets on Monday to discuss the possibility of New Zealand's alert level dropping to Level 2.
He estimated that "some time in the next couple of weeks will be the right time to come out of Level 3 and go to Level 2.
Professor Hendy said Cabinet's decision will likely rest on how confident they feel about their contact tracing systems, because contact tracing during a lockdown was much easier at Level 4 than Level 2.
"Contact tracing has obviously been very effective in drawing lines around those clusters - but that has been enabled by the fact that we've been in lockdown," Professor Hendy said.
"While we're in lockdown we all have many fewer contacts - so it's easier for the contact tracers to find those people."
It would be a fine line, he said, as the true numbers from Level 3 would only start to come through later this week, and even through the weekend.
What he'd like to see in the numbers are "a few more zeroes" and not a slow rise back to double digits, which would indicate that Level 3 has begun to spread the disease again.
"Let's keep our fingers crossed that we do start to see a few more zeros."
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