Key Points
- You are now able to get a fifth COVID-19 vaccine.
- People now have access to a bivalent vaccine that targets Omicron subvariant BA.1.
- A new bivalent vaccine targeting Omicron subvariants BA.4 and BA.5 won't be available until 6 March.
Many Australians have raced to get their fifth COVID-19 vaccine jab after eligibility was opened up this month - but there's concern those who rushed to be jabbed first are not getting the best protection.
Georgie Whitton, 76, has been anxiously waiting for months to become eligible for the bivalent vaccines, which were available in Australia in October, but .
It has been almost 12 months since her last booster, something that has caused her stress and worry, given her husband is immunocompromised and she also has health issues.
Ms Whitton finally got her booster on Tuesday 21 February but afterwards she was upset to discover she was given a bivalent vaccine that only targets Omicron variant BA.1. She was expecting to receive the latest vaccine, which targets the BA.4 and BA.5 variants. It does not become available until 6 March.
BA.4 and BA.5 were the main Omicron variants circulating in Australia towards the end of last year, although there has since been an explosion of new subvariants with transmission being including Omicron subvariants: BA.4.6, BA.2.75, BQ.1 and XBB.
While the latest Pfizer bivalent does not target the latest variants, it's thought it does provide slightly better protection than boosting with the original vaccines, and experts say it's still worthwhile as a protective measure.
Ms Whitton said she had rung her local pharmacy specifically to check she could be vaccinated with the BA.4/5-specific vaccine and was assured that they already had the latest Pfizer jab in stock and could provide this to her on 21 February.
Georgie Whitton is disappointed she was not given the latest booster that protects against Omicron subvariant BA.4 and BA.5. Source: Supplied
But when she later checked her vaccination certificate, she realised she had been given the Moderna bivalent, which only targets BA.1.
She said it was "extremely annoying" to realise she had been given the less effective vaccine.
"I'm 76, I've got a lot of cardiac troubles and asthma, so naturally I wanted the best protection, not just for my husband but for me as well."
She said many Australians had rushed to get their booster on 20 February as for many it had been nine or 10 months since their last jabs.
"So there are a lot of people who are going to be in the same boat as me, and now we need to be assured that we're going to be able to get the stronger vaccine [and] not having to wait another 12 months," she said.
"What they're doing is they're putting all of the people who've rushed in as quickly as they could to get boosters that put them in a sort of, second-class group."
Ms Whitton said she would have been happy to wait another two weeks to get the BA.4/5-specific booster.
"It was only two weeks difference, I would have happily waited," she said.
What boosters are available to Australians?
Australians aged over 65 are now eligible to get a fifth vaccine dose. Currently, they can get the new bivalent vaccines from either Moderna or Pfizer that specifically target Omicron BA.1. They can also choose to get the Novavax vaccine as a booster, as well as the original Pfizer or Moderna vaccines.
From 6 March, Pfizer's new bivalent vaccine that targets BA.4 and BA.5 will also become available. On 17 February, the Therapeutic Goods Administration (TGA) also approved a new Moderna vaccine that targets BA.4 and BA.5 but it's unclear when this will be available.
Australians can now access new bivalent vaccines. Source: AAP / Diego Fedele
The (ATAGI) has recommended people get boosted before June, and around six months after their last vaccine dose or COVID-19 infection.
Should people wait for the latest bivalent boosters?
University of Queensland infectious diseases physician Associate Professor Paul Griffin said there was likely a subtle improvement with boosting with one of the new B.A 4/5 vaccines rather than the BA.1 version, even though there was not a lot of data comparing them.
"We think that's probably just a bit more of a better match compared to what's circulating at the moment, so likely to be a slight improvement" he said.
"But people certainly shouldn't feel shortchanged if they've recently had a BA.1 booster because that protection will still be very much worthwhile."
Professor Griffin said he thought people should chat with their GP, pharmacist or other vaccine provider about their options, what vaccines were available and which might be the best one for them.
Given the BA. 4/5 vaccine would be available in around two weeks, and there appeared to be a modest benefit, Professor Griffin said it could potentially be worth waiting.
"[But] if there's any delays to that - if it's inaccessible - it'd be much better to have a BA.1 booster than to wait a long period of time and potentially get COVID in the interim," he said.
"Given we're seeing transmission starting to maybe go up in some states we certainly don't want people to wait too long but there probably is the opportunity to wait at least a few weeks if we don't see a big increase in cases in the meantime."
Overall, Professor Griffin said the B.A 4/5 boosters were thought to provide better protection against hospitalisation or death when compared to boosting with the original vaccines.
Given we're seeing transmission starting to maybe go up in some states we certainly don't want people to wait too long but there probably is the opportunity to wait at least a few weeks if we don't see a big increase in cases in the meantimeAssociate Professor Paul Griffin
He said a US study had shown the B.A 4/5 boosters offered around 35 per cent better protection against hospitalisation or death. Another UK study found protection against hospitalisation was about 20 per cent higher.
ATAGI has noted that the B.A 4/5 booster also produced higher neutralising antibody levels against newer BQ.1.1 and XBB.1 subvariants than with the original vaccine.
Professor Griffin said it was difficult to predict how quickly any new boosters would be made available to the public in the future.
"If we saw a new, more significant variant emerge in the coming weeks, there may be a specific booster response to address that," he said. "Outside of that - and that's pretty unlikely - it would seem less likely that we're going to recommend another dose between now and winter.
"An additional dose could be recommended at any time, depending on what happens with the virus, and what we see with the epidemiology, but hopefully this could also be the last booster that we see this year."
