Australia's already sluggish and voluntary COVID-19 vaccine rollout has been dealt a confidence blow by the changing health advice regarding the AstraZeneca vaccine.
Mid-rollout, Australia's vaccine experts in the Australian Technical Advisory Group on Immunisation (ATAGI) have increased the recommended age for AstraZeneca from 50 to 60, changing the preferred vaccine for millions of people.
The move, after two deaths in Australia - most recently that of a 52-year-old woman - out of almost 4 million vaccinations, reflects a conservative approach - but the decision was not taken lightly.
Who gets AZ?
The locally produced AstraZeneca COVID-19 vaccine is now only recommended for Australians aged 60 and over.
AstraZeneca is "strongly recommended" for Australians aged over 50 years who have already had the first dose.
The federal Government says it has no plans to abandon the AstraZeneca vaccine. "We've got very clear medical advice that the benefits of being vaccinated for the over-60s are strong and clear," Greg Hunt said.
Who gets Pfizer?
Pfizer is now the recommended vaccine for Australians aged under 60. There are no other available options in Australia.
The change will increase demand for the Pfizer vaccine and the government has moved to open access immediately for 40- to 59-year-olds.
Can I mix my vaccines?
The health advice discourages following up an AstraZeneca dose with a Pfizer shot, and encourages sticking to AstraZeneca, regardless of age, if you have already had the first shot.
"There are some trials looking at a mix-and-match approach, and some countries have gone down that path," chief medical officer Professor Paul Kelly said. "But there is very little evidence that it is either effective or safe."
"And in fact some of the evidence we have so far is you actually get more of [those] immunogenic short-lived symptoms in the first 24 hours if you do AstraZeneca-Pfizer."
If I follow health advice am I in danger?
AstraZeneca is still a very safe vaccine.
The decision to change the health advice is made on a conservative recommendation concerning a very rare adverse reaction to AstraZeneca. The extremely rare blood-clotting condition known as thrombosis with thrombocytopenia syndrome (TTS) has led to two deaths from 3.8 million doses in Australia.
The Therapeutic Goods Administration says TTS is triggered by the immune system's response to the AstraZeneca vaccine, and is different from other clotting conditions.
Hunt says Australia now has one of the most conservative age ranges in the world for AstraZeneca. He says AstraZeneca is offered to people over 40 in the UK, over 30 in South Korea and over 18 in Germany. It is, however, recommended to people over 65 in Sweden and Finland.
If it does happen, the adverse reaction to AstraZeneca almost always only occurs after the first injection.
Why did it change?
ATAGI changed its recommendation after the second reported death in Australia just over a week ago.
The 52-year-old NSW woman died earlier this month from a clot in her brain. It is not known if she had any underlying health problems, but she was over the then-recommended minimum age of 50 for receiving AstraZeneca.
The Health Minister said the experts had to balance the risks of the vaccine with the risk of COVID-19, which is not currently widespread in Australia.
"Given the absence of that, and the capacity to provide the Pfizer for the under-60s, they felt that the balance of risk had moved in favour of Pfizer for under-60s and AstraZeneca for over-60s," Mr Hunt said.
Will they change the advice again?
The Health Minister says the government and health officials have had to be flexible in the response to the pandemic.
"We're adapting immediately, and we're able to do that," Mr Hunt said on Thursday.
When will we reach 'Covid normality' or herd immunity?
NSW Premier Gladys Berejiklian says Covid normality won't be achieved until at least 80 per cent of the population is vaccinated.
The federal Health Minister is shy of targets.
"It's a progressive process," Mr Hunt said.
"The more people who are vaccinated, the safer we are. And I think that's the very clear message. The more people who are vaccinated, the safer each of us is."
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