Moderna's COVID-19 vaccine has been approved by Australian health authorities for children as young as 12.

The vaccine was already approved for adults 18 and over, and the Therapeutic Goods Administration has now extended that approval down to teenagers.

It brings the vaccine into line with the extremely similar Pfizer vaccine. Both are based on MRNA technology.

The two vaccines are the only vaccines available to children, with the AstraZeneca vaccine only available to adults over 18.

While both are approved for children aged 12 and over, there is no vaccine for children under 12, and no country in the world has made COVID-19 vaccines broadly available for that age group.

The Moderna vaccine is due to arrive in Australia later this month.

It will likely be made available primarily in pharmacies, and will only be made available to people under the age of 60.

While the TGA has approved the vaccine for those 12 and over, vaccine expert advisory body ATAGI will also provide its advice on Moderna's use.

All children from 12 to 15 years of age can book a Pfizer appointment from September 13, and those in a priority group can book now.

More to come