Chief Medical Officer Professor Paul Kelly says the Omicron variant appears to be more prevalent in younger people.
"What we know about that already is it is highly transmissible and we’re seeing the rise in cases every day, as has been predicted, as has been seen in many other countries that have Omicron," Professor Kelly said during a media conference on Wednesday.
"Even in the UK, and the same here, we are still seeing most of the cases in younger people, so there is still that little bit of doubt about what happens in older people here in Australia in relation to Omicron."
Professor Kelly said during the outbreak there have not been large numbers of people from aged care in hospital, as was seen prior to vaccination and during the Delta outbreak.
"But it is a new challenge – certainly those numbers of cases as the PM has mentioned is putting, as we’ve seen, a strain on our PCR supplies," he said.