The federal government is projecting there will be little need for the AstraZeneca COVID-19 shot after October, with Pfizer and Moderna to become the key vaccines.
For the first time, the Health Department has released long-awaited projections detailing the vaccine doses each state and territory will be allocated each week for the rest of the year.
The modelling forecasts that the AstraZeneca vaccine will be phased out, with demand falling after the over-60s have been vaccinated.
The AstraZeneca vaccine is currently only recommended for people aged 60 years and older, while Pfizer is the preferred vaccine for the under-60s.
The new data predicts that by October, at least 1.7 million doses of Pfizer will be made available to the states and territories each week, while a minimum of 430,000 Moderna doses are forecast to be handed out weekly between October and December.
COVID-19 Taskforce commander Lieutenant General John Frewen said the data was being released to improve transparency and to allow states and territories to better plan for the year ahead.
"What these figures provide is each of the jurisdictions with the likely minimum amount of doses of each of the available vaccines, and the likely upper range of supply that we would receive," he said.
"This is giving the states all of the best information we can to help them plan to get all of the vaccinations that we can provide to their citizens as quickly as possible."
Lieutenant General Frewen said the AstraZeneca vaccine would still be available to states beyond October if they requested it.
"The assumption is … for all of the people and cohorts where AstraZeneca is preferred, we think they will have received their AstraZeneca before the fourth quarter," he said.
"For any people who still do require AstraZenca, we will have allocations available into the fourth quarter and we fully expect there will be adequate supplies."
According to the projections, between July and August at least 650,000 Pfizer vaccines will be distributed to the states each week.
The number will ramp up to 930,000 each week from September.
Moderna vaccines are expected to be made available from September, pending TGA approval, with 87,000 doses distributed to the states on a weekly basis.
The "Covid Vaccinations Allocations Horizons" document states that allocations will be locked in four weeks in advance, once supply is confirmed with vaccine manufacturers.