An extra 1.5 million Australians are eligible for a fourth COVID-19 vaccine dose under new guidelines from ATAGI.
Interim Health Minister Katy Gallagher said she had received the advice this week.
A fourth dose is now recommended for people with underlying health conditions and people who have a disability.
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They will be able to receive the fourth dose from May 30.
This is alongside the previously eligible categories: people aged 65 and over, residents of aged care homes, people who are severely immunocompromised, and Indigenous people aged over 50.
"Essentially, for people who think they fall into that category, check it out and make sure you are getting your fourth dose," Gallagher said.
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The updated advice from ATAGI comes ahead of a winter where it's feared the flu will strike vulnerable populations alongside a resurgent COVID-19.
Gallagher said there was no issue with vaccine supply.
However, a fourth dose was not yet being advised for the general population.
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"So their clear advice is that the fourth dose extension is for those people who would be most susceptible and most vulnerable to severe disease from contracting COVID," Gallagher said.
She said the incoming full-time health minister, who is set to be sworn in next week, will receive a full briefing on COVID-19 in Australia, including whether further measures were needed to address it.
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