While the Commonwealth is rolling out the nation's vaccine program primarily through GP clinics across the nation, the states have been tasked with inoculating some smaller portions of the population, including frontline workers.
However the West Australian government has banned residents under the age of 50 from getting the jab.
"People under 50 who are booked in to receive their AstraZeneca vaccine will have their appointments cancelled," WA Chief Health Officer Andrew Robertson said in a statement.
Tasmania has taken a similarly cautious move. "The Tasmania government has put an immediate hold on any first dose AstraZeneca vaccinations of people aged under 50 years," the state government said in a statement.
On Friday, NSW followed suit.
“NSW Health has temporarily paused administration of the AstraZeneca vaccine to all age groups at its clinics this [Friday] morning while the informed consent information is updated,” a statement said.
“AstraZeneca vaccinations for those aged 50 years and over will recommence later today.”
NSW was tasked to vaccinate roughly 300,000 people before offering to do more earlier this week. But as states wait to sort through the logistics stemming from the updated advice, a large cloud hangs over the country's vaccine rollout which is highly dependent on the local production of the AstraZeneca shot.
After suspending the vaccination on Friday, NSW Premier Gladys Berejiklian announced jabs for over-50s had recommenced and those under 50 would still be able to receive it from Monday.
"The best health advice that we've received is that it is safe for people to have the AstraZeneca vaccine if they're under 50 years of age," the premier said on Friday.
“The only reason we took a pause this morning was to update all of our clinicians."
Queensland Premier Annastacia Palaszczuk said the rollout in the state was "business as usual" and it would continue to administer the AstraZeneca jab until it received more Pfizer doses, which are now the preferred vaccine for people under 50.
Younger NSW residents will be able to make their own choices about getting the AstraZeneca vaccine if they're eligible.
Rare side-effect a 'spanner in the works'
Australian Medical Association vice president Dr Chris Moy worked closely with the government on its GP-led vaccine strategy. He admits the latest health advice is a "spanner in the works" to the rollout, but much of the short-term plan can proceed without disruption.
At the GP level, most of those currently eligible to be vaccinated are over the age of 70 and won't be impacted by the change in health advice.
"But within the hospitals – say they're doing frontline healthcare workers with AstraZeneca – there's going to be a much higher rate of under 50s and it may complicate their clinics," he said of the state's renewed caution.
The AMA's position is that we should be following the advice of independent scientific experts that got us through this," Dr Moy said.
"The Federal Government have done that.
"We would expect the states to do this, we understand this has put a spanner in the works and effected the logistics ... Especially if there is a high proportion of those under 50 because the whole consent process has changed."
Dr Moy said there would no doubt be hassles at state clinics and GP offices on Friday, but implored people to seek out how the updated advice impacts them personally and make their own judgement.
While the potential side-effect is very rare – about 5 or 6 in a million – Dr Moy admitted sentiment problems could plague the particular jab.
PM says focus remains on vaccinating the vulnerable
On Friday afternoon, Prime Minister Scott Morrison said his government was working with the states to "recalibrate" the national rollout, but remained upbeat about the immediate future of the scheme as the focus remained on the elderly.
"We are talking about groups where we can continue to proceed with the vaccination rollout at the pace we are hoping to proceed at," he said.
"The most vulnerable people in our community are not just over 50, they are actually a lot older than that. The AstraZeneca vaccine is well suited to address those critical vulnerable groups.
"So vaccinating our elderly Australians remains a key priority that also supports the continued opening up of Australia because the risk factor of severe illness amongst the most vulnerable is therefore reduced."
He said the reported blood clot side effects were very remote.
"We are talking in the vicinity of five to six per million which is a rather rare event," he said.
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