No further changes to COVID-19 booster shot intervals, CMO says

No further changes will be made to the interval between the second dose of the COVID-19 vaccine and booster shots, Australia's Chief Medical Officer has said.

The duration between the second dose of a COVID-19 vaccine and the booster shot was recently reduced from six months to five months.

Chief Medical Officer Paul Kelly announced today no further changes would be made to the interval for booster vaccines, as a shorter interval reduces the efficacy of inoculation.

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"It remains anyone who has had their second dose five or more months after that they are now eligible for that booster dose," he said.

He also asked vaccine clinics to be flexible around the five-month period between the second shot and booster due to clinics closing for Christmas.

"ATAGI is urging anyone who is giving vaccines to be a little flexible about that five months given that clinics may be closed or people may be travelling. If you're a week or two before the five months, you know, that's fine," he said.

Vaccine efficacy against Omicron variant

Professor Kelly's announcement comes as all Australians are urged to come forward for their booster shot to increase their protection against the Omicron variant.

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Professor Kelly said the vaccine is not as effective in stopping transmission of the virus, which explains the "very rapid transmission" in the New South Wales outbreak.

He said early evidence shows the vaccine does, however, prevent hospitalisations as a result of Omicron.

"We also know, and this is new information, that the vaccine remains effective against severe disease, perhaps a little less than it is the case against Delta, for example, but it does remain effective," he said.

"I think that's one of the reasons why we are seeing increases in cases but not so much of an increase in hospitalisations or other forms of severe disease, so that is important."

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Booster shot shortage

There have been reports of a booster shortage in Australia, which Lieutenant General John Frewen addressed today.

Lieutenant General Frewen said some GPs and pharmacies are running low in booster shots due to the rapid change in advice.

"It's less than a week since we got the change in the ATAGI advice from six months to five months," he said.

"Instead of 1.7 million people due, there's now more than 4 million people due at the end of the year."

More vaccines have been ordered and Lieutenant General Frewen said there should be "no concern about the amount of supply".

The incoming delivery of vaccines arriving next week will be the largest number of shots since the beginning of the rollout.