Nearly a fifth of Australia’s Covid vaccine stock binned amid warning of fresh wave of cases

Australia binned almost 20% of its national Covid vaccine supply last month while leading epidemiologists and doctors have warned the country will face another wave of cases in November when existing immunity wanes.

Millions more vaccines are due to arrive in Australia before the end of the year, with the first Omicron-specific version of the Moderna shot becoming publicly available on Monday.

But a steady supply of the vaccine is being met with dwindling demand, with the country wasting 17.6% of the national stockpile in September.

After a slow start getting the vaccines into the country, there is now a lag in getting boosters into arms. More than 95% of eligible Australians have had two doses of a Covid vaccine since the rollout began in February last year, while 72% have received a third shot and only 40% a fourth.

Gaps in immunisation are leaving Australia open for a new wave of cases in November, modelling from the University of South Australia suggests.

It would unlikely be as high as the peak from the BA.5 Omicron strain, but the slow booster rollout would lead to an increase in hospitalisations, he said.

The BA.4/BA.5 subvariants of Omicron are still the dominant strains across the country but there are concerns new variants will be more transmissible.

"It'll be a lower peak, but the problem at the moment is there are a number of subvariants - at least four that are more transmissible than BA.4," Esterman said. "They're making inroads in places like Belgium, Germany and the UK, we have them in Australia and there's a chance they'll take over BA.5."

Two doses alone offer little defence from the new variants, with protection from serious illnesses and hospitalisation waning over time, Esterman said.

"That will create another wave. We have these new subvariants BA4.6, BA.2.75, BQ.1 all of these can escape our immune system better than BA.5."

The government does not publicly supply data on the exact number of vaccines being destroyed. In October last year a 1% to 2% wastage rate was recorded.

According to a Australian National Audit Office report, the government has spent more than $8bn on Covid vaccines. In 2021 42.6m vaccine doses were administered.

The Department of Health defended the amount of doses being thrown away, as the World Health Organization stipulates that for multi-dose vaccines an acceptable level of wastage is between 15% and 40%,

"We carefully manage vaccine stocks to minimise wastage and ensure that all doses are distributed efficiently and effectively," a spokesperson for the department said. "While all avenues to avoid wastage are explored, wastage can be expected as part of any vaccination program."

An associate principal research fellow at the Burnet Institute, Mike Toole, said about 20% was a normal amount of wastage, but the booster rate was concerning.

"Our booster rate has been creeping up very slowly, it's only really gone up 5% over the last few months," Toole said.

"There's a stubborn group of people that got two shots but have not taken up a third or a fourth. We still have quite a large portion of the population that is not protected by vaccines."

Toole said there had been a slight increase in the reproduction number - on 9 September it was 0.86 and was now 0.98. In Queensland, Western Australia and Victoria it was 0.99, he said.

"In those three states the decline has come to an end and now on Friday we get rid of the isolation period," Toole said. "One to two weeks after the isolation period ends the [reproductive number] will go above one across the country."

"You have the recipe for another wave and that's without taking into consideration any new variants."