(Image: Mitchell Squire/Private Media)

Vaccination goals behind the government’s four-phase plan for a vaccinated Australia have been released by the national cabinet. Phase B of the plan, which will ease restrictions on vaccinated Australians, allow student and economic visa holders entry along with increased caps for returning Australians, and reduce the likelihood of lockdown will occur when around 70% of Australian adults have received two doses of the vaccine. 

Phase C will start when more than 80% of the population is vaccinated and will abolish caps on returning vaccinated Australians, extend a travel bubble between countries, and result in highly targeted lockdowns only. 

These targets are set on having those aged 16 and above inoculated, with booster shots planned, focusing on reducing hospitalisation and serious illness over case numbers. 

But the data doesn’t make sense: While the national cabinet received a briefing from the Doherty Institute on Friday, it’s not clear how this has been interpreted to set the vaccination targets. Taking into account the whole of the population — not just those aged over 16 — drops these vaccination goals from 70% to 56% and 80% down to 64%. 

Anything less than 80% is risky

Modelling released by the Grattan Institute last week showed ending lockdowns and reopening borders will be possible once 80% of the total population is vaccinated, and 95% of those aged over 70. While the report deems 80% “ambitious” it notes that it could happen before the end of the year if a vaccine is approved for children under 12. 85% vaccination rates would be needed for all international border restrictions to be removed for vaccinated people. Whether this is achievable is another question: countries around the world have yet to hit 80% vaccination rates with vaccination rates slowing around the 60-70% mark.

Modelling by James Cook University found that to address the Delta variant, 85% of the population would need to be vaccinated to reach herd immunity. This could drop to 75% if there was close to 100% uptake among the most infectious ages from 20 to 60-year-olds, which is unlikely. 

Professor Stephen Duckett, who prepared the Grattan Institute report, told Crikey the government’s goals were “risky”. 

“The benchmark the government have effectively set is 56% and 64% and that’s what’s concerning. What matters is the actual rate of the whole population,” he said. 

Why are young people being excluded?

AstraZeneca and Pfizer vaccines have been approved for those aged 12 and above, so setting the target for those aged 16 and above is odd, and out of step with a lot of countries. Excluding those aged under 16 in the data is a concern with the Delta variant, which is causing respiratory illness in children and is more transmissible across all age groups. In the UK, infections are rising quickly among those aged 10 to 19 — a major concern for schools. 

World Health Organisation adviser and epidemiologist Mary-Louise McLaws told Crikey the goals seemed “cavalier”.

“They lack a duty of care. If you’re only going to have 56% of the population vaccinated, that’s nearly every other person unvaccinated,” she said.

“This does not keep us safe. This is going in the opposite direction.”

Even for other variants, a 56% vaccination goal is a low number, but for the Delta variant, which has a viral load of roughly 1000 times more than the original strain — meaning there’s more of the virus in each infected person’s body to spread — it’s particularly risky. In the US, masks are advised to be worn indoors even by the fully vaccinated in response to increasing COVID-19 cases caused by the delta variant. 

What goals do other countries have?

Singapore has a target of vaccinating 75% of its total population, while New Zealand modelling estimates 80-85% of the total population would need to be vaccinated before restrictions can be eased. Germany has set its sights on 85% of all people aged 12 to 59 to be vaccinated, while US experts estimated between 60% and 90% would need to be vaccinated to achieve herd immunity — though this goal was set prior to widespread Delta variant infections.

Compared to international benchmarks, Australia’s targets to reopen the country aren’t just low — they’re incredibly, incredibly risky. The Doherty Insitute modelling, and the government’s interpretation of it, has yet to be released.