Health Minister Greg Hunt says a decision to lift the recommended age for the AstraZeneca coronavirus vaccine hasn't blown the rollout off course.

Australia's troubled coronavirus vaccine rollout has hit another roadblock after medical experts recommended raising the AstraZeneca age limit to 60.

But Health Minister Greg Hunt insists the nation remains on track to offer all Australians over 16 a jab by the end of the year.

AstraZeneca is now the preferred vaccine for people over 60 with Pfizer recommended for anyone under that age.

The expert immunisation panel ATAGI recommended the change because of extremely rare but serious blood clots that have claimed two lives of people in their 50s.

"For those aged 60 years and above, the individual benefits of receiving a COVID-19 vaccine are greater than in younger people," ATAGI said in a statement.

"The risks of severe outcomes with COVID-19 increase with age and are particularly high in older unvaccinated individuals."

Mr Hunt said people aged 50 to 59 would have to be patient with 2.1 million in that group yet to receive a first dose.

But the minister remains confident Pfizer imports will not cause further supply issues.

There are concerns Australia's strategy has been too heavily weighted on 50 million locally produced AstraZeneca doses.

Deputy Labor leader Richard Marles told parliament the prime minister bet the house on AstraZeneca and now the rollout was in complete disarray.

Mr Hunt is pinning his hopes on the balance of 40 million doses of Pfizer and 50 million Moderna jabs arriving as contracted during this year.

"Pfizer has been a remarkably reliable partner. They have never over-promised and they have always delivered on time," he said.

He expects 3.4 million doses to land in Australia over the next six weeks.

The Victorian government remains at odds with their federal counterparts on Pfizer supply and has asked for longer-term delivery projections to help planning.

Health authorities have encouraged the 815,000 Australians who have had their first dose of AstraZeneca to receive a second jab because of dramatically lower risk than the initial shot.

Opposition Leader Anthony Albanese said fewer than three per cent of Australians had been fully vaccinated against coronavirus.

"The government has failed to meet any of its vaccine targets. It failed to secure enough vaccine deals," he told parliament.

More than 6.2 million doses have been administered nationwide since the rollout started in February.

A coronavirus outbreak in Sydney's eastern suburbs has grown to three cases after a woman was exposed to the virus at a cafe.

A nurse who previously tested positive for COVID-19 while treating infected patients also worked shifts at a second Melbourne hospital.

But Victoria recorded no new locally acquired coronavirus cases ahead of a further easing of restrictions on Friday.

Meanwhile, Australia will closely watch coronavirus hospitalisation numbers in well-vaccinated European nations as the government mulls a return to international travel.

Scott Morrison said the impact of high people movements during the northern hemisphere summer would be revealed.

"If the virus is there but the hospitalisations and the serious illness don't occur and we see that on a sustained basis, well that says there is a potentially different pathway there," he told Sky News.

"But the jury is not in on that yet. New variants like Delta and so on can change all that."