New Covid vaccine now available
A new vaccine touted to target the Omicron strain of COVID-19 has been introduced in Australia, making it the first vaccine containing both the original and Omicron strain to enter the country.
A spokesperson for the Department of Health and Aged Care confirmed that the Moderna Spikevax bivalent (or combination) vaccine would join the national vaccine rollout from Monday, October 10, and be available to Australian adults as a booster dose.
"The Moderna bivalent vaccine will be integrated into the existing COVID-19 booster program and all sites participating in the COVID-19 vaccine roll-out program will have access to this vaccine in coming weeks," the spokesman said.
"People who are due for a COVID-19 dose are encouraged not to wait and to book an appointment as soon as possible, using whichever vaccine is available to them."
It comes after the TGA (Therapeutic Goods Administration) provisionally approved the vaccine as a booster for adults over the age of 18 on August 29.
ATAGI (Australian Technical Advisory Group on Immunisation) recommends that the new vaccine is administered three months after your last vaccine or COVID-19 infection - but that you only need it if you’re not up-to-date with your boosters.
For most people, four doses of a Covid vaccine are recommended, while immunocompromised people are recommended to get five.
How is it different from vaccines we already have?
Like current vaccines, the Moderna bivalent vaccine is an mRNA vaccine that contains genetic blueprints for spike proteins found in the original strain of COVID-19.
When we get a Covid jab, the vaccine prompts our body to build replicas of the protein that alert our immune system to respond by producing antibodies - creating an immune “memory” that can then neutralise the real virus if we are infected with Covid.
But, this new Moderna vaccine differs in that it also includes the blueprints for spike protein of the Omicron BA.1 subvariant which was circulating earlier this year.
Associate Professor Paul Griffin, an infectious disease physician at the University of Queensland, told SBS News that the term “bivalent” refers to the vaccine’s ability to target two virus variants instead of one.
Though the vaccine only targets the BA.1 variant, Professor Griffin said it appears to provide extra protection against subvariants BA.4 and BA.5, which are circulating in Australia currently.
"[It] has been shown to give better protection against Omicron, including later Omicron subvariants BA.4 and BA.5 that have caused the recent waves in Australia," Professor Griffin explained.
In the Omicron variant - which includes the BA.1, BA.2, BA.3, BA.4, and BA.5 subvariants - the spike protein has at least 30 mutations that have changed the shape of the protein slightly in comparison to the original virus.
As a result, original Covid vaccines are less effective at neutralising infections caused by these subvariants, since the antibodies these vaccines created are less likely to recognise the Omicron spike protein.
How effective is it?
ATAGI have said that Moderna’s bivalent vaccine showed a small benefit over original vaccines for fighting Omicron variants, while a study published in the New England Journal of Medicine found that those who received the new jab had a greater antibody response to BA.1, BA.4 and BA.5.
However, it is still unknown how these levels of antibodies translate to preventing infection, hospitalisation and death, or how long the antibodies last.
Where can I get it?
If you still need a booster shot, you can find your nearest clinic using the health department’s clinic finder which can be accessed here.
Image: Getty Images