Almost one-fifth of Australia’s total stock of COVID-19 vaccines had to be thrown out last month, as dwindling demand meant many doses went unused.
But leading epidemiologists warn that the nation is facing another wave of COVID infections in November, as immunity from boosters begins to wane.
After the rush (despite a slow start) to have everybody double vaccinated, there has been an alarming drop-off in booster take up, The Guardian reports.
Currently, more than 95 per cent of eligible Australians have had two doses of a COVID vaccine, 72 per cent have had a third dose but only 40 per cent have had a fourth.
Professor Adrian Esterman, chair of biostatistics and epidemiology at the University of South Australia, says modelling completed by his team indicates case numbers will begin to rise again next month.
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“The modelling has estimated another wave in November simply because of waning immunity, and it’s likely to happen nationwide,” he says.
“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,” Prof. 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.”
While Australians rushed to get double jabbed in the early stages of the pandemic, the end of restrictions and official isolation periods seems to have lulled some into a false sense of security and a feeling they don’t need to continue getting boosters.
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Professor Mike Toole, assistant principal research fellow at the Burnet Institute, says having a wastage rate of 20 per cent for vaccines was fairly normal, but that the uptake of boosters was a more pressing concern.
“Our booster rate has been creeping up very slowly, it’s only really gone up 5 per cent over the past few months,” he says.
“There’s a stubborn group of people who 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.”
Although cases numbers have been dropping since their peak in July, there has been a slight increase in the reproduction number, or the ‘R’ number, that represents the number of additional people an average COVID case will infect.
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If the number pushes past one, it means an effective doubling of COVID case numbers every few days. At the moment, Queensland, Victoria and WA each have an R value of 0.99.
“In those three states, the decline has come to an end and now on Friday [last week] we get rid of the isolation period,” Prof. Toole says.
“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.”
Are you up to date with your COVID boosters? Are you worried about a new wave of cases? Let us know in the comments section below.