It’s expected some five million vulnerable Aussies will be able to get a fourth dose of COVID-19 vaccination this winter after health authorities warned of a seasonal case spike.

The Australian Technical Advisory Group on Immunisation (ATAGI) is expected to green light a fourth dose on Wednesday for anyone aged over 65, in aged and disability care or severely immune compromised.

The fourth dose will not yet be required to be considered fully vaccinated but Federal Health Minister Greg Hunt said earlier this month Australia’s vaccine advisory group would likely recommend it by the end of March for vulnerable groups.

Severely immunocompromised people aged over 16 were already eligible for a fourth dose, but the next phase of the rollout is expected to begin before winter.

The period between third and fourth jabs is yet to be confirmed, but it is likely to be about four or five months.

The country’s federal and state leaders will also meet at a national cabinet meeting on Wednesday to discuss isolation rules for household contacts.

Prime Minister Scott Morrison was very keen to scrap the seven-day isolation mandatory period for household contacts two weeks ago when he called isolation “redundant” and asked for urgent medical advice on the subject.

“We all know what it’s like with kids and flus … you know, they bring it home, and then the whole family has to stay home and can’t go to work. So that rule is becoming, we believe as leaders, redundant,” he said.

But experts have warned this wouldn’t be the smartest move since the highly contagious the BA.2 subvariant had led to a spike in infections.

NSW and Victorian health officials have urged the PM to delay any changes to rules to help stop the rise in case numbers.

BA.2 is now dominant in NSW and experts have attributed its high-transmissibility to the state’s escalating outbreak.

NSW recorded 24,115 new cases on Wednesday, up from Tuesday’s 20,000. Victoria recorded 10,471 new cases overnight.

Cases were expected to peak at about 30,000 per day in April and we’re quickly closing in on that figure.

NSW Health Minister Brad Hazzard recommended reinstating mask mandates and the dancing ban earlier this month but we’re yet to cop any new restrictions.

Experts in other states have also been concerned. Queensland case numbers rose 15 per cent in one week, while Tasmania has recorded more COVID-19 cases in this outbreak than any other thanks to BA.2.

Vaccine efficacy has also waned because only 62.5 per cent of the population has received a third dose, which experts said has further contributed to rising case numbers.

If you haven’t yet had your first booster, for the love of God please go out and get it now.

Image: Getty Images / Sean Gallup