Scott Morrison has rejected modelling that warns Australia could face 25,000 deaths and 270,000 cases of long Covid if lockdowns and public health restrictions end once 80% of the adult population is vaccinated.
Morrison told 3AW radio on Tuesday the modelling by researchers at three leading Australian universities was “not realistic” because public health measures would continue after lockdowns ended and vaccination rates would continue to climb.
Expert views on the modelling exercise led by Dr Zoë Hyde, an epidemiologist from the University of Western Australia, were mixed.
The chair in epidemiology at Deakin University, Prof Catherine Bennett, told Guardian Australia the modelling proved Australia’s national plan was a “sensible way” out of Covid restrictions because the aim was “to get cases back under control in Sydney and Melbourne” before reopening.
But the Grattan Institute’s health and aged care program director, Dr Stephen Duckett, backed the new modelling, arguing it supported Grattan’s conclusion Australia should only reopen once 80% of all Australians were vaccinated or risk higher reproduction rates of Covid.
The Doherty modelling, which underpins the plan adopted by national cabinet, looked at the number of deaths in the first 180 days of reopening at the 70% and 80% vaccination thresholds that lead to phase B and C – when lockdowns would be “less likely” and then “highly targeted”.
The latest research models total cumulative deaths over a longer timeframe during phase D of the national plan – when no restrictions remain.
The Doherty modelling suggests that in the first 180 days after Australia reopens at an 80% of adults vaccination rate, there would be 761 deaths with partial testing, tracking, tracing and quarantine (TTIQ), or 1,457 at 70%. Deaths would fall to as few as six with “optimal” TTIQ and 80% of adults vaccinated.
In their paper, published on Tuesday but not yet peer-reviewed, Hyde and her co-authors suggested that once 80% of adults were vaccinated, which translated to 65% of the population overall, there could be approximately 25,000 fatalities.
Ensuring all children were vaccinated could reduce the death count to 19,000, or to 10,000 if 90% of adults were vaccinated.
Morrison said he didn’t “agree with that assessment” because “they assume that … vaccinations don’t continue to rise” beyond the 80% target.
“They assume there’s no other public health measures in place and all of that,” he told 3AW. “So, I mean, that’s, that’s not a realistic scenario and that’s not what is going to happen.”
Morrison said the Doherty Institute was “one of the most significant scientific agencies in the world” and had concluded Australia can “move ahead” safely once the 70% and 80% targets were reached “with appropriate public health measures, which doesn’t mean lockdowns”.
The Doherty Institute director, Professor Sharon Lewin, told ABC’s 7:30 that deaths could reach 25,000 “if we have no public health measures” and “just rely on vaccination”.
But Lewin said public health measures – such as masks, checking in, testing, tracing and isolating, and “limited” lockdowns – were “a key part of the model”.
“The short answer is there is no freedom day here.”
Bennett told Guardian Australia that at the start of the most recent Delta outbreak, New South Wales had reduced reproduction to 1.3 through soft lockdown measures despite low vaccination rates.
Once vaccination rates reached the 70% and 80% targets, Bennett said the reproduction rate would “be able to be kept below one” – meaning each person infected with Covid passes it on to less than one other person on average.
Bennett said the new modelling suggested “we do nothing and continue to do nothing as cases rise”. “But it’s not all or nothing, which is what they’ve modelled.
“People are fearful of starting to ease off restrictions. But we’ll start to see it in our numbers, start to see that control come in [as vaccination rates rise].
“There might be some easing of restrictions along the way to help people’s mental health that doesn’t undermine what we’re trying to achieve.”
The Grattan Institute’s modelling found that with 70% of the total population vaccinated and a starting reproduction rate of six, Australia could expect 15,900 deaths.
Duckett said the new modelling was “not inconsistent” with Grattan’s conclusions because they had asked the same question “what do you need to do to live without lockdowns”.
“We found it is probably safe to open at 80% of the whole population, which is not out of whack with what that new modelling shows: they said 90%, we said 80% growing to 85% and 90% over time.”
Duckett said the government had asked the Doherty Institute “the wrong question”, by seeking criteria to move to phase B when lockdowns were “less likely”.
He said the national plan was “completely and utterly vague” because “the prime minister is saying the states signed up to this national plan, but they signed up based on the particular situation at the time”.
Duckett said Morrison had sold the benefits of the national plan based on “optimal” testing, tracing, isolating and quarantine, but it was clearly only “partially effective” because Covid-19 was “rampant” in New South Wales.
The Australian Greens leader, Adam Bandt, has written to Morrison asking for children above the age of 12 to be included in the national cabinet’s vaccination targets.
The federal government was preparing a school-based vaccination rollout for children aged 12 to 15, but Morrison had ruled out counting them in the national plan targets.
On Tuesday, the Australian Capital Territory chief minister, Andrew Barr, said the 70% and 80% targets were “important milestones but they reflect the opportunity to take gentle and measured steps forward in the national plan”. Barr announced the ACT would count children aged 12 to 16 in its vaccination targets.
