Simon Bridges says the Government shouldn't be relying on "scare tactics" to get people vaccinated against COVID-19.
At Thursday's 1pm press conference Government advisor Shaun Hendy, a disease modelling expert at Te Pūnaha Matatini, presented modelling which suggested 7000 Kiwis could die a year if New Zealand's vaccination rollout stalls at 80 percent of those currently eligible, even with continued isolation and quarantine measures for those who contract the virus.
WIthout those measures - a return to normality, so to speak - nearly 9000 a year could die at that same level of vaccination. These figures assume the vaccine offers 85 percent reduction in transmission and 94 percent against severe disease.
Some other countries with around 80 percent vaccinated have started to open up or plan to soon, the latest being Portugal. Others - such as Singapore - are still experiencing growing outbreaks.
Rodney Jones, an economist on the Government's COVID-19 advisory panel who also does disease modelling, told RNZ there is "no way New Zealand would experience anything like that", calling Dr Hendy's presentation "a side-show".
Bridges, former leader of the National Party, told The AM Show if Te Pūnaha Matatini's figures encourage people to get vaccinated "then okay, but I don't think we need scare tactics".
"There's been a lot of debate, including from Rodney Jones who I rate as an eminent, internationally-renowned modeller."
According to the modelling, the number of hospitalisations and deaths drop off markedly as vaccination rates hit the 90s - down to 1557 with isolation and quarantine measures at 90 percent coverage, and just 123 at 95 percent. If kids as young as five are included in the vaccine rollout, as is expected to be the case eventually, 95 percent coverage would cut the expected number of annual deaths to just eight.
"I think we should try for 90 percent… we should go for that," said Bridges, echoing Prime Minister Jacinda Ardern.
"I do worry about the realism though. In the end we should do everything we can, but we can't [wait until] 2023 for example, stay shut down and locked up. In the end in a free democracy people are ultimately - even if we think they're all wrong - free to decide these things. I think everyone should get vaccinated, but the truth is, some won't."
If everyone who's currently booked in for a second dose shows up, but no one else, we'll get to just 69 percent fully vaccinated.
Senior Labour MP David Parker, appearing with Bridges on The AM Show, said reaching 90 percent would allow us to "open up safely without lockdowns and people can get all the freedoms back that we used to [have]. Get back to the new normal."
But it's still not a target.
"We've deliberately never set a target and I'm not doing that today… you might characterise it that way. Lots of my colleagues have acknowledged that if we get to 90 percent vaccination we can reopen, and we can reopen safely.
"A few months ago people were saying our target should be 70 percent… we're up over 80 percent first doses in Auckland now. It's going well, but we've got to get that last 10, 15 percent."
Seventy percent might have been enough with the original strain of COVID-19, but not Delta, which is twice as infectious.
Overseas jurisdictions with high vaccination rates have continued to see new cases, as the current vaccines don't completely stop transmission between vaccinated people - but they do significantly reduce the chance of serious illness (by 90 percent) and death (by slightly more than that).
Most deaths in highly vaccinated countries are still among the unvaccinated.
The US Centers for Disease Control and Prevention recently reported 84 percent of all those who died of COVID-19 in the US between June 20 and July 17 were unvaccinated. Nearly two-thirds of all Americans (of any age) have had at least one jab.
In the UK, only 256 out of 51,000 deaths recorded between January and July were among people who were fully vaccinated, and didn't already have the virus before immunity had reached its full strength, which takes about two weeks after the second dose.