The government's original promise was that four million people would be vaccinated by early April and everybody else by October.
We are in early April but, on the latest figures, 841,885 had been given either the AstraZeneca or the Pfizer jab by the beginning of this week, clearly well below the aim.
On top of that, the new advice from the chief medical officer Paul Kelly that people under 50 should not receive the AstraZeneca vaccine unless the "benefit clearly outweighed the risk" will clearly not hasten roll-out.
What's on order?
Australia has bought nearly 140 million doses of vaccines of different brands, most of it imported but some made under licence from AstraZeneca in Melbourne.
The supply of the Pfizer vaccine has been smooth. About 140,000 doses arrive every week, destined mostly for quarantine and health workers in the first phase of the program.
The glitch has been with the AstraZeneca vaccine. It has emerged that in a tiny number of recipients blood clots occur.
What's gone wrong?
Firstly, nothing may have gone wrong. This is a complex, unprecedented task where uncertainties abound and a lot of talented people are doing their best. There never was a blueprint in someone's drawer which could just be pulled out.
But a delay is a delay.
The problems with the AstraZeneca vaccine are rare but still serious. Many medicines have side-effects and doctors work out a balance between risk and benefit.
Professor Kelly said the clotting was "an extremely rare event".
"We are talking about four in a million, around that, but it is a serious event. So this is the system of post-market evaluation and following up of vaccines once they are in the real world."
And the delay in supply stems from difficulties with the European Union.
Prime Minister Scott Morrison blamed the EU for not delivering a promised (as he saw it) 3.1 million doses of the AstraZeneca vaccine "that we had been relying upon in early January when we'd set out a series of targets did not turn up in Australia". "That is just a simple fact."
Agriculture Minister David Littleproud accused the EU of cutting Australia "short" of the vaccine. "We are three million short at the moment," he said. "They cut us short."
But the European Union denied it had actually blocked the request.
This may be semantics. The Australian government suggested that the EU had refused permission to export which in its book amounted to blocking. "If you're not approving, it's the same as effectively you're blocking," Treasurer Josh Frydenberg said.
The full truth is not known but there is a lot of politics going on in the EU over the pace of vaccination.
It's been slow to get its rollout rolling and EU leaders have received flak as other countries, particularly Britain, have got their programs going faster.
But Australia produces its own AstraZeneca
AstraZeneca has licensed the Melbourne company, CSL, to manufacture its vaccine. On top of 3.8 million doses from Europe (including the 3.1 million doses in dispute), CSL would make 50 million doses.
The original aim was for CSL to ramp up its production to a million doses a week by the end of March. That hasn't happened.
Health Minister Greg Hunt said the government had received 1.3 million locally produced doses so far, including 830,000 initially released on March 24. In other words, the rate of production was below the million a week originally anticipated.
But the production of vaccines and the logistics of distribution are complicated.
"There are risks in accelerating and pressuring the supply chain purely to hit an arbitrary deadline. Even with the very best planning and control, novel supply chain systems are notoriously fragile and frequently crack under excessive pressure," two experts in logistics, Elizabeth Jackson and Sharyn Curran of Curtin University, wrote.
CSL seems to be increasing production steadily and ironing out glitches early so that the system is reliable when it's at capacity.
In particular, it's improving its way of approving batches for release.
The health minister said he expected the company to reach the million doses a week in the near future.
The Prime Minister is cautious on timing: "There is an expectation, I think, of certainty, and of guarantees here that the environment does not provide for."
The view of experts is that the start has been slow but the program will speed up.
"Although things have started slowly and we are behind where we would like to be, our slow start will likely ramp up significantly in the coming weeks," epidemiologist Hassan Vally of La Trobe University said.
"It is significant that we have now entered phase 1b of the rollout, which means many millions more are now eligible to get the vaccine. We have also now started onshore vaccine production, which ensures vaccine supplies into the future.
"Yes, there have been frustrations. But unlike many places, Australia has the luxury of time to carefully and safely deliver the vaccines due to our excellent performance so far in containing the spread of COVID-19."
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