Prime Minister Scott Morrison's strategy of relying on the AstraZeneca COVID-19 jab to vaccinate the majority of Australians faces a new challenge this morning.

The shock news that the United Kingdom will move to recommend alternatives for under-30s over blood clot fears is a further blow to Australia's fraught rollout program.

The European medicines safety committee urged countries overnight to continue to use the Oxford/AstraZeneca vaccine in all age groups but issued warnings that unusual blood clots should be listed as a very rare side effect.

Despite that finding that the vaccine is safe and the benefits outweigh the risks, the UK moved swiftly overnight to declare the AstraZeneca vaccine should not be given to under-30s if an alternative is available.

England's deputy chief medical officer Professor Jonathan Van-Tam said that the risk/benefit balance for the AZ vaccine for younger people could be finely balanced because they are less likely to die from COVID than older people. It is not because the vaccine is not safe or more likely to cause blood clots in younger people.

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"Clearly this is a course change, we don't want it to result in a loss of vaccine confidence,'' Professor Van-Tam said.

UK Prime Minister Boris Johnson insisted the Oxford/AstraZeneca vaccine was "safe" speaking shortly before the televised briefing.

"But the crucial thing for everybody is to listen to what the scientists, the medical experts have to say later on today,'' he added.

The AstraZeneca vaccine is the main vaccine Australia has based its entire vaccination strategy around with the vast majority of Australians expected to be jabbed with the locally produced AZ shot produced by CSL.

That means any recommendations to restrict the use of the vaccine in certain age groups in Europe, particularly by the UK, could have flow-on effects here at home and will be reviewed by Australian health authorities in coming days.

Mr Morrison flagged this threat to Australia's COVID-19 rollout during a press conference on Wednesday.

The move by UK Prime Minister Boris Johnson to restrict the rollout of the AstraZeneca jab among under-30s is a blow for Australia's vaccine program. Picture: Dave Thompson / Pool / AFP

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The Prime Minister has moved to reassure Australians that the best weapon the nation has to deliver vaccines to the masses is the decision to develop local production at CSL, conceding that if he had not insisted on that, there wouldn't be a vaccine program.

But he warned there are still risks to that supply and one potential factor is any updated medical advice on vaccines. The only locally produced vaccine at this stage is the AstraZeneca vaccine.

"Even domestic production - there can be impacts on domestic production,'' the Prime Minister said.

"There is always the conditioning factor right across the vaccination rollout of the medical advice and the development of medical evidence that can in any way affect any of the vaccines. And so, there are no absolute guarantees when it comes to this. We will follow the medical advice. We will continue to ramp up production here in Australia. And we will continue to move through the distribution channels that can deliver the supply of vaccines that we have."

Chief medical officer Brendan Murphy said that the cases were extremely rare, but Australian officials were working closely to assess the risks.

"I just want to mention the issue in relation to vaccine safety. There has been some attention related to this issue with clots potentially associated with the AstraZeneca vaccine, and clearly there's been the reports of a possible case in Australia,'' he said.



"One case is not a strong signal, but we are working very closely with our counterparts in UK who have now done well over 18 million doses of this vaccine, and in Europe that have done many million, to look at the data that they're getting from their signals and their regulatory bodies and their vaccine advisory committees, and that's what's going to give us the true picture of whether this is a real problem and whether it has any significance.

"The benefit of vaccination outweighs any potential risk. But we are continually reviewing the situation."

Emer Cooke, the head of the European Medicines Agency (EMA), said she also wanted to stress the vaccine was safe and effective.

"European medicines agency has confirmed that the benefits of the AstraZeneca vaccine in preventing COVID-19 overall outweighs the risks of side effects,'' she said.

"It's important that both vaccinated people and healthcare professionals are aware of the signs and symptoms of these unusual blood clotting disorders, so that they can be spotted quickly to minimise any possible risks."



Originally published as Vaccine U-turn a blow to Australia

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