Some Australians could soon be rolling up their sleeves for a fourth COVID-19 vaccine jab as authorities try to reduce the threat of a rapidly spreading Omicron sub-variant.
With coronavirus cases rising steeply in New South Wales and Victoria, plans to scrap stringent isolation rules for households are also now in doubt.
The country's chief health officers and state officials will discuss the isolation rules at an Australian Health Protection Principal Committee meeting today.
READ MORE: What are your chances of getting COVID-19 more than once?
NSW and Victoria health officials had been working towards loosening isolation rules which require entire households to stay home and isolate if a family member tests positive.
But changes to those measures may now be in doubt, after new case load projections based on Omicron's more transmissible BA.2 sub-variant were presented.
It is expected the BA.2 sub-variant will become the most dominant strain in Australia by the end of March.
EXPLAINED: What is the Deltacron variant of COVID-19 and how dangerous is it?
READ MORE: How will COVID-19 end? Experts look to past epidemics for clues
That shift has also sharpened thinking around a proposed fourth jab for millions of Australians before winter sets in, with the Australian Technical Advisory Group on Immunisation (ATAGI) expected to sign off on the extra dose today.
Infectious diseases expert Professor Robert Booy said the new strain posed a serious health risk to the elderly and immuno-compromised.
"There is up to half-a-million Australians who will (immediately) benefit from a fourth dose," he said.
Professor Booy estimated ATAGI would probably recommend people get a fourth jab three-five months after receiving their third dose.
Cases in Australia's two post populous states have risen as students returned to school, and some health experts are concerned just 43 per cent of 5-11 year olds are fully vaccinated.
READ MORE: Sydney international airport still eerily quiet
