Despite significant delays in the government's vaccination timetable, Australia has no plans to buy the single-dose Johnson & Johnson vaccine that has helped the US fully vaccinate millions of people.
The vaccine rollout here was further slowed last week due to changed health advice surrounding the use of the AstraZeneca vaccine for people under 50.
But despite those delays, the government is pointing to a key similarity between the vaccines as a reason not to purchase Johnson & Johnson's product — they're both built with adenoviruses.
What is an adenovirus vaccine?
Adenovirus vaccines are a type of viral vector vaccine.
That means they use a modified and harmless virus — in this case an adenovirus — as a delivery system for genetic instructions.
Those genetic instructions teach your body to produce spike proteins like those that adorn the outer shell of SARS-CoV-2, the virus that causes COVID-19.
When your body begins producing the harmless spike protein, your immune system reacts and learns how to fight the real thing.
Both AstraZeneca and Johnson & Johnson use adenoviruses in their vaccines, which have some key benefits over other types of COVID vaccines.
They are easier to manufacture than mRNA-based formulas like the Pfizer and Moderna vaccines.
They can also be kept at regular refrigerated temperatures, as opposed to the freezing temperatures needed to preserve mRNA vaccines for long periods.
Why isn't Australia purchasing Johnson & Johnson?
Currently, AstraZeneca (an adenovirus vaccine) and Pfizer (an mRNA vaccine) are approved for use in Australia.
The AstraZeneca vaccine is also produced locally, at CSL's plant in Melbourne.
Supplied: CSL
)Health Minister Greg Hunt said the government's vaccine advisory body had not provided advice that the Johnson & Johnson vaccine should be purchased.
The Theraputic Goods Administration (TGA) confirmed it has recieved an application from Johnson & Johnson for the "provisional registration" of its vaccine in Australia.
The TGA said the application is being assessed, adding that it "will approve any therapeutic or vaccine for use when the benefits outweigh the risks".
The vaccine could be accessed with a prescription if approved and if Johnson & Johnson decide to make the vaccine available privatley, the TGA said in a statement.
Does this have anything to do with blood clots?
Archie Clements, a professor of infectious disease epidemiology at Curtin University, said the government may have been stung by recent links between the AstraZeneca vaccine and a very rare blood clotting disorder.
The rollout of that vaccine was knocked off course last week after its association with the condition became clearer.
The vaccine is still being encouraged for people over 50, but it is only recommended for younger people if the benefits clearly outweigh the risks in individual circumstances.
"The government is probably feeling a certain amount of political discomfort around the promotion of AstraZeneca earlier on and the reliance on AstraZeneca," Professor Clements said.
Last week, Chief Medical Officer Paul Kelly said the rare clotting condition was "most likely" brought on by an immune response to the adenovirus in the AstraZeneca vaccine.
But he could not be definitive.
Europe's drug regulator is reviewing rare blood clots in four people who received the Johnson & Johnson vaccine, but the company says at this stage there is no causal link.
AAP Image: James Ross
)Dr Khai Lin Huang, an infectious diseases physician at the Burnet Institute, said it was too early to tell whether those instances had anything to do with the Johnson & Johnson vaccine.
"They are adenovirus-based. But whether or not that is the pure reason [behind the clots] … We don't know, it's too early. It’s too early to be drawing conclusions," he said.
"I'm not too concerned and can understand the rationale behind the decision. It doesn't seem unreasonable, with what information is available to us currently."
The AstraZeneca-linked condition is exceptionally rare, affecting between four and six people per million vaccinated.
Out of the millions of people vaccinated with the Johnson & Johnson vaccine, just four are being investigated as potential blood clotting cases.
This morning, a second case of the clotting disorder was reported in Australia, out of 700,000 doses of the AstraZeneca vaccine administered.
https://news.google.com/__i/rss/rd/articles/CBMiZWh0dHBzOi8vd3d3LmFiYy5uZXQuYXUvbmV3cy8yMDIxLTA0LTEzL3ZhY2NpbmUtam9obnNvbi1qb2huc29uLWFzdHJhemVuZWNhLWFkZW5vdmlydXMtY292aWQvMTAwMDY0Njc00gEoaHR0cHM6Ly9hbXAuYWJjLm5ldC5hdS9hcnRpY2xlLzEwMDA2NDY3NA?oc=5
2021-04-13 05:08:13Z
52781502127079
Bagikan Berita Ini
0 Response to "What is an adenovirus vaccine? The reason Australia isn't asking for the Johnson & Johnson jab - ABC News"
Post a Comment