Advice limiting the use of the AstraZeneca vaccine in younger Australians would likely be overturned if there was a significant coronavirus outbreak.
Expert vaccine advisers to the federal government have told The Sunday Age and Sun-Herald that Australia’s near elimination of coronavirus was central to its decision to preference the Pfizer vaccine for those aged under 50.
But they warned this outlook could change.
The Australian Technical Advisory Group on Immunisation warned it was still a possibility that COVID-19 could leak into the community and cause death and disease, despite Australia’s strict border controls.
Leading epidemiologist Jodie McVernon said the low rate of coronavirus in Australia was the reason experts had chosen a more cautious approach to the UK, which is still giving the green light to AstraZeneca vaccinations for anyone aged 30 and over.
Director of Doherty Epidemiology, Professor Jodie McVernon.Credit:Simon Schluter
“If you’re in the UK right now, if you’re in France, or Italy, or the United States, where there are raging epidemics, your risks of COVID and your risk of severe outcomes of COVID are very different,” said Professor McVernon, director of Doherty Epidemiology and an invited expert to the federal government’s vaccine advisory group.
While cases of COVID-19 in the UK have fallen dramatically this year, the country is still reporting about 3000 new cases each day and dozens of deaths, meaning British health experts came to a different conclusion when weighing the importance of a link to a rare but dangerous clotting syndrome.
The thrombosis with thrombocytopenia syndrome is estimated to affect four to six people in every million who receive the AstraZeneca vaccination.
Professor McVernon said she had no doubt if there was a “major incursion” of coronavirus and uncontrolled community transmission in Australia, the local advice on the AstraZeneca vaccine would be reassessed.
“The committees, ATAGI and everyone else would be back to the drawing board and reassessing that risk-benefit equation,” she said.
This view has been backed by ATAGI executive team member Kristine Macartney, who warned that while there were many tools to control the pandemic, “control is always precarious”.
“We would be signalling that the benefits [of the AstraZeneca vaccine] would certainly outweigh the risk if we were starting to see a big swing up in community-based transmission,” Professor Macartney said.
Epidemiologists have warned that vaccination of hotel quarantine workers would not entirely eliminate the threat of outbreaks in Australia.
University of South Australia professor Adrian Esterman said the biggest risk was the possibility of either the British or the South African variant breaking out in Australia.
“The South African variant really is quite nasty and current vaccines don’t work very well against it,” he said.
Asked what sized outbreak would result in a change of advice on the AstraZeneca vaccine in Australia, ATAGI co-chair Professor Allen Cheng said on Friday that the issue would be continually reassessed as new information emerged.
He said the rate of cases in the UK was comparable to the peak of Victoria’s second wave, when more than 700 daily cases were detected in the state, and he believed above that level the benefit of getting vaccinated with AstraZeneca “well and truly outweighs the risk”.
“At the moment in the UK, it’s probably a bit [of a lineball decision] in people over 30 but … even just going back one month, the benefit in preventing COVID was clearly on the side of getting vaccinated,” he said.
Professor Cheng said ATAGI’s decision to draw the line at preferring the Pfizer vaccine over AstraZeneca for those aged under 50 took into account the possibility of a coronavirus outbreak in Australia in the coming months or year.
The chance of people dying from coronavirus dramatically increases in older age. For example, almost 10 per cent of those aged in their 70s who got coronavirus in Australia died (159 of 1623 people). In comparison, two men in their 30s died out of 5228 cases in this age group.
Burnet Institute epidemiologist Mike Toole said it was important the virus was kept out of the community, and he called for a national quarantine protocol to be developed to bring in consistent standards of infection control.
“Then we don’t have to panic about the vaccine program,” he said. “But if we get another breach of quarantine, which will probably happen in Perth, Sydney or Brisbane, with a bit of bad luck that hotel worker could have a high viral load and variant and then spread it, rapidly.”
Get our Coronavirus Update newsletter
Stay across the news you need to know related to the pandemic. Sent Monday and Thursday. Sign up here.
Most Viewed in National
From our partners
Source: Read Full Article