The NSW government has temporarily suspended giving the AstraZeneca coronavirus vaccine, amid growing uncertainty about Australia’s national rollout.

Late on Thursday, the Australian Technical Advisory Group on Immunisation recommended the AstraZeneca vaccine not be given to people under 50, who face a very slight risk of developing blood clots.

The advice has thrown the national coronavirus vaccine rollout into disarray, further jeopardising the federal government’s commitment to have all Australians vaccinated with at least one COVID shot by October.

NSW joins other states to react speedily to the changing advice.

NSW Health said on Friday it would halt all AstraZeneca shots until official “informed consent information” was updated.

“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,” it said.

“AstraZeneca vaccinations for those aged 50 years and over will recommence later today.”

The Western Australian government has banned residents younger than 50 from getting the AstraZeneca vaccine.

“People under 50 who are booked in to receive their AstraZeneca vaccine will have their appointments cancelled,” WA chief health officer Andrew Robertson said.

People in the 1a and 1b vaccination program cohorts – including health workers – who are under 50 and have already had their first AstraZeneca vaccine, should “not be alarmed”. They should go ahead with their second jab.

“You should not cancel your second vaccination booking,” Dr Robertson said.

Tasmania followed WA on Friday morning. The state government will contact 1400 eligible Tasmanians to tell them their AstraZeneca shots are off.

Premier Peter Gutwein said the state’s vaccine program would require “recalibration” after the latest advice.

“In terms of what this change means for Tasmania’s planned vaccine rollout, we are working our way through that,” he said Friday.

In Victoria, people arriving for vaccinations on Friday were turned away if they were under 50.

St John’s Ambulance worker Athena (no last name given) told the ABC in Melbourne she was prepared to have the AstraZeneca shot, despite the blood clot risk. But she had been denied it.

“It’s pretty minimal [risk], from what I heard. It’s less than that contraception pill,” she said.

“I understand there’s a risk but it’s frustrating I didn’t get notified. That’s the most annoying thing for me.”

South Australia’s health authorities were discussing their response on Friday. Chief public health officer Nicola Spurrier said an information hotline was one possible idea to help address concerns.

“It’s going to be messy today, I don’t think there’s any way around that,” Professor Spurrier said.

Pfizer is now the preferred vaccine for people aged under 50.

The issue was top of the agenda at Friday’s national cabinet meeting, along with state border closures.

Professor Spurrier conceded a return to normal life and the opening of the national border was going to be delayed following the new advice.

“It’s going to slow it down, it’s unfortunate but it is what it is,” she said.

Following the change in advice, chief medical officer Paul Kelly said “nothing is off the table”, suggesting the government was considering a deal with Moderna to redress vaccine shortfalls.

“We are looking at all of those options right now. We know that Novavax – we have 51 million doses on order – is not yet approved by the TGA.

“The TGA will absolutely expedite that matter and as soon as Novavax is ready to supply to Australia we will be going through those processes,” Professor Kelly said.

Announcing the change in advisory in a hastily called media conference on Thursday night, Prime Minister Scott Morrison said the vaccination program would be recalibrated over the weekend as officials came to grips with the change.

“The overall impact of this on the timetable of the rollout, it is far too early,” he said.

Australia was relying on AstraZeneca jabs to be the backbone of coronavirus immunisations through 50 million locally produced doses.

Labor has lambasted the government for failing to secure more deals with other vaccines successfully being rolled out to millions of people worldwide.

Opposition Leader Anthony Albanese described the rollout as a debacle and demanded certainty about when Australians would be vaccinated.

“This government has failed. This government couldn’t run a choko vine up a back fence,” he said on Friday.

Health Minister Greg Hunt defended the government’s vaccine portfolio, arguing the AstraZeneca change was made out of an abundance of caution.

“We’ll get through it. We’ll protect everybody,” he told ABC radio.

“There will be some adjustments but we’ll keep everybody safe and we’ll get them vaccinated.”

More people under 50 will now receive the Pfizer jab with health workers pushed to the front of the queue.

But Australia has a contract for only 20 million doses of the Pfizer – enough for 10 million people – and fewer than one million have been delivered.

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The rare blood reaction to the AstraZeneca shot has appeared in four to six people for every million to receive the jab, with a 25 per cent death rate for people who develop the syndrome.

A man in his 40s who was admitted to hospital in Melbourne is the only person in Australia to develop the problem.

AstraZeneca noted Australia’s decision factored in having no community transmission of the virus.

“Overall, regulatory agencies have reaffirmed the vaccine offers a high-level of protection against all severities of COVID-19 and that these benefits continue to far outweigh the risks,” it said in a statement.

The advice compounds the federal government’s headaches with the rollout already under fire for lagging behind most other developed nations.

While 51 million doses of the promising Novavax shot could be added to the effort from October, that vaccine is yet to gain approval anywhere in the world.

-with AAP