Case numbers are "back to reasonable levels", University of Auckland computational biologist Dr David Welch says. Photo:
New Zealand is "well past" the most recent peak of Covid-19, with wastewater results consistent with low case numbers, an expert says.
The third Covid-19 wave of 2022 put a dampener on many people's Christmas holidays, but appeared to infect fewer in total than earlier outbreaks.
University of Auckland computational biologist Dr David Welch told Morning Report it was hard to know exactly how many infections were out there but all signs pointed to numbers being "back to reasonable levels".
The seven-day rolling average of community cases was 2738, which was down compared to last Monday's average of 2996.
"We don't know exactly how many infections there are, but everything points to much fewer now than there were three or four weeks ago." University of Auckland computational biologist Dr David Welch
Welch said the Christmas break, and people spending time outdoors, had helped - acting as a "circuit break" and meant the number of cases did not reach what it could have.
Less testing was expected as people only tended to test nowadays if they had symptoms and there were fewer symptoms around, Welch said.
But wastewater results also showed fewer infections.
"We don't know exactly how many infections there are, but everything points to much fewer now than there were three or four weeks ago."
Welch said the most recent wave had been driven by new variants in the community - and fewer numbers meant there were less people susceptible to the virus that it could infect.
Case numbers would stay low with higher immunity in the population - and until new variants came along.
Welch told Morning Report he was in favour of better surveillance - including a prevalence survey and testing at the border.
It would help give officials a better idea of what was coming in from overseas - and what New Zealand could expect to face in months to come.
"Particularly somewhere like China, where the information coming out of there is negligible, so really, we've got to rely on our own surveillance to understand what is happening there."
The government has decided not to test people arriving from China following the country's relaxing of travel rules.
However, there would be voluntary testing of travellers from China.
Covid-19 Response Minister Ayesha Verrall said that would involve emailing a random sample of people recently arrived from China to ask them to undertake a RAT test and share that information with health authorities.
"It's entirely voluntary and we have had high uptake from international visitors when we used this method before."