A study which suggests New Zealand could offer quarantine-free travel or shorter stays in quarantine to arrivals from countries that have COVID-19 under control has been rejected by a disease modelling expert.
Research commissioned by the aviation sector suggests loosening border restrictions to countries with a low level of COVID-19 infections.
But disease modelling expert Professor Shaun Hendy says he doesn't support the call.
"The particular approach they've taken is not one I'd support," he told the AM Show on Friday.
"They [the report] decided to look at COVID fatalities. One of the difficulties is, if you just want to look at raw case counts from overseas, you've got to scale them somehow."
"A lot of countries just don't test enough. So if we look at the UK and the US, they're probably way underestimating the number of cases they have.
Hendy says this is particularly the case in countries where there are large outbreaks and not everyone gets a test, leading to undercounting.
"So this group [the aviation sector] said, 'okay what if we look at COVID fatalities,' but the difficulty is, the deaths run about three weeks behind infections, so if you're only watching deaths, we wouldn't close our borders fast enough."
The study used a model to evaluate the risk of allowing travellers from low-risk countries to enter New Zealand without going through the full MIQ process.
It claimed loosening border restrictions results could allow five times more people to enter New Zealand, but could increase the risk of the infection spreading to the New Zealand community by 20 to 50 percent.
"This information may be useful in guiding decision-making on selectively opening of borders in the COVID-19 era," the report said.
"Even at current MIQ capacity, we are still seeing infections occurring regularly within facilities in both workers and travellers, which puts us at risk of another Auckland August type outbreak," Hendy said.
If we were to loosen MIQ restrictions, it "would increase the frequency of MIQ failures, the chances of a larger outbreak, and the chances of another regional lockdown by something like 20 to 50 percent," Hendy said.
Professor Michael Plank, a mathematical modeller at the University of Canterbury, says it makes sense to have a risk-based approach - but the preferred approach from the aviation sector goes too far.
"We will need a framework of this type to relax border restrictions once the world begins to emerge from the pandemic."
"However, COVID-19 is more prevalent now than at almost any point in the past. At the moment, we need to do everything we can to reduce the risk of importing COVID-19 into the community, not taking on additional risk."