Convincing the 20 per cent of West Australians who aren’t fully vaccinated to roll-up their sleeves is the priority, but those eligible for a booster should get it before the border opens.
That’s according to Professor Christopher Blyth, the Perth-based co-chair of the Australian Technical Advisory Group on Immunisation, which advises the Federal Government on COVID-19 vaccines.
Over the weekend, the body approved the Moderna vaccine to be used as a booster shot for Australians aged 18 and over. It can be used irrespective of what vaccine a person received for their primary course.
ATAGI also cut the waiting time for boosters from six months after a person received their second dose down to five months.
The change was in response to the emergence of the Omicron variant, which early data from the UK and South Africa has shown was likely more transmissible than Delta but may cause less severe illness.
Prof Blyth said it was difficult to know if Omicron would replace Delta as the dominant strain by the time WA restarts quarantine-free domestic and international travel in late January or early February.
“Given the speed at which Omicron has become the predominant strain in Africa, it is something that we do need to be concerned about, to watch very closely and to learn quickly about,” he said.
“Whether it becomes a predominant strain in other countries is yet to be determined and also how frequently it causes severe disease compared to previous strains remains uncertain.”
Prof Blyth, of the University of WA and Telethon Kids Institute, said a third dose improved protection against Omicron and ATAGI supported use of Pfizer or Moderna for boosters irrespective of which vaccine people received earlier in the year.
Both are mRNA vaccines, with the main difference being that the Moderna booster dose is half the amount given for the primary course.
There are 193,000 West Australians who received their second dose five or more months ago and are now due a booster.
By the time the border reopens in seven or eight weeks’ time, 678,000 WA residents will be eligible for a third shot.
Despite this, Prof Blyth said the “absolute critical need” was to ensure the one-in-five West Australians not yet fully vaccinated get their first two jabs.
As of Friday, 88.7 per cent of West Australians aged 12 and over had received at least one dose and 79.3 per cent were double-dosed.
“The most important step is to ensure that everyone who is eligible has their two primary doses,” Prof Blyth said.
“What we do see is, particularly for some, waning may occur. If you are eligible, which is now five months since your second dose, I would be encouraging all West Australians who are eligible to have a booster — and ideally prior to opening up of borders.”
Department of Health Secretary Professor Brendan Murphy said the waning immunity of the primary vaccination means a booster would be “very important” to continue protection against Omicron.
“We are still protected with our primary vaccination, people shouldn’t be worried. But boosters are very important to give that extra immunity, particularly as the Omicron variant is likely to spread around the world,” he said.