Australia's top vaccine advisory body has approved the Pfizer vaccine for children aged 12 to 15 who have underlying medical conditions or are from an Indigenous background or remote communities.
Children with severe asthma, diabetes, epilepsy who are immunocompromised are among those who will now become eligible for the vaccine.
The decision to include them in the rollout was signed off by the Australian Technical Advisory Group on Immunisation, ATAGI, after being recommended by the Therapeutic Goods Administration last week.
Deputy Chief Medical Officer professor Michael Kidd said around 220,000 children would now be given priority access to the vaccine.
"The children who are being offered vaccination when this program starts are the children who are at the greatest risk," he told reporters.
The rollout officially begins on 9 August, but GPs are free to start administering vaccines to eligible children before then as part of phase 1B of the vaccine program.
Health Minister Greg Hunt said ATAGI had made it clear "from the outset" that the vaccine rollout would be opened up to children in two stages.
"They identified there was a significantly greater risk for those who are immunocompromised or with underlying medical conditions," he told reporters.
He said the medical advisory group was still considering "international evidence" around the broader rollout of the vaccine to all children aged 12-15.
"The early indications are certainly that they were leaning towards that decision but they did want to see the international advice," he told reporters.
During cases have been linked to two schools, with four others considered high-risk exposure sites.
Professor Kidd said while both Australian and overseas evidence showed increased transmissibility of the Delta variant among young adults, this was not evident among children.
"We're not seeing that among children - but we are following very closely what is happening," he said.
