The data is in: the risk of developing blood clots following the AstraZeneca vaccine was overhyped.
Two new UK-based studies released this morning found that the increased risk of rare blood clots associated with the vaccine affected just 0.9–3 in 1 million people, while blood clots in the brain affected one in 4 million people.
According to the Therapeutic Goods Administration (TGA), across the 13.7 million doses of the vaccine administered in Australia, there were 172 cases of thrombosis with thrombocytopenia syndrome (TTS), with 88 of these cases confirmed to be linked to the vaccine.
But experts say these figures don’t show the whole story and that more interpretation is needed.
Is this surprising?
The UK studies looked at the health records of 46 million adults in England, 21 million of whom were vaccinated with AstraZeneca, finding a very small increase in the rate of thrombosis following the jab.
For brain blood clots, researchers analysed 11 million UK-based adults and found there was double the risk of developing a rare brain clot after getting the vaccine.
So, are these decreased rates of rare incidents surprising? In short, no. While the risk of developing blood clots appears higher in TGA figures, the rate of developing TTS dropped as certain age groups were excluded or discouraged from getting the vaccine. Fatality rates also dropped as people became aware of the early warning signs and could seek treatment for TTS.
As infectious diseases and vaccine expert Professor Robert Booy tells Crikey: “You can quote all sorts of figures, it’s so heterogeneous. What we need to understand is which group was at highest risk and what was their absolute risk.”
“I think the studies probably underestimated risk because surveillance is not perfect in such a large number of people.”
Most people experience an adverse reaction to the first AstraZeneca jab, and those people are at a higher risk of developing another adverse reaction to the second jab.
“We responded very, very quickly to the problem. We adjusted our strategies so that we reduced the risk of those things happening,” Booy said.
Professor David Tscharke, head of the department of immunology and infectious diseases at the Australian National University, similarly said the decreased global figures weren’t surprising.
“It’s a really great example of how we actually do vaccine safety in real time,” he said.
Were the risks overplayed?
Mixed messaging around who was eligible for the AstraZeneca vaccine slowed uptake during the initial stages of the rollout. Prime Minister Scott Morrison pressured the Australian Technical Advisory Group on Immunisation (ATAGI) in July 2021 to change its advice to get younger people to wait for an mRNA vaccine while there were differing opinions from experts about who should get the jab.
In July, the then-Queensland chief health officer Jeannette Young was accused of “scaremongering” following comments saying she didn’t want anyone under 40 taking AstraZeneca and “dying from a clotting illness”.
Morrison also gave doctors indemnity for advising younger patients and administering AstraZeneca, meaning they couldn’t be sued if the patient experienced an adverse reaction.
“Communication was messy, that was clear,” Tscharke said. “The public was confused because they didn’t understand the role of the various official and unofficial voices and there were some very unfortunate messages.”
A key issue was that for everywhere but Victoria, the risk of catching COVID-19 was minimal due to low transmission. Tscharke said then, and now, that more needed to be done to highlight the dangers of COVID-19.
“This is a completely brand-new viral disease. We’re still finding out there are long-term risks associated with viruses that we’ve known for a long time,” he said.
“Whereas with vaccines, history tells us that long-term risks are very, very unlikely — the closest thing to zero that I would ever say as a scientist.”
Booy said pursuing the rollout of AstraZeneca last year was the right thing to do. “When there were no other [vaccinie] options, the cost-benefit ratio favoured AstraZeneca vaccine considerably,” he said.
“It’s all down to timing.”
Many young Australians approached the jab with this mentality too — despite ATAGI’s advice and mixed messaging, across July 2021 over 340,000 people under 40 came forward for the jab.
‘Most people experience an adverse reaction to the first AstraZeneca jab, and those people are at a higher risk of developing another adverse reaction to a second jab’ I think is badly phrased.
I had two AstraZeneca shots, and didn’t have any side effects. I had the Pfizer booster, and felt tired on the day of injection, and developed slightly tender axillary lymphadenopathy on the side of the injection 4 days later.
I think what’s meant is ‘Most people who develop an adverse reaction to the AstraZeneca vaccine do so on the first dose, and those people are at a higher risk of developing another adverse reaction to the second jab.’
No adverse reaction on the first dose meant the recipients were safe to have the second dose.
Yes I agree. At 80 I had a similar experience as did my son, aged 54. We both had AZ shots with no side effects whatsoever and felt weary for about 36 hours after a Pfizer booster.
At 76, I similarly had no side affect from the two AZ shots and only a tender site when touched after the Pfizer shot
Spouse & I, 70 & 75 respectively, had A/Z x 2, noticed nothing.
Last month I had booster of A/Z, the better half went for Pfizer, just to compare notes.
Page remains blank.
Exactly. This is very sloppy journalism:
Most people experience an adverse reaction to the first AstraZeneca jab
We (83 and 80 respectively) had 2 doses each of AZ in June and September with no side effects. We had a Pfizer booster each 3 weeks ago and were warned by the Dr. administering it that we could and probably would have side effects: sore/ swollen injection site which 1 of us (me) had, sore and stiff joints, back and general increase in muscle stiffness, headaches, possible sore throat, fatigue. All of which we have at our age! Advice was to take paracetamol for 4-5 days and plenty of fluids, both of which we do anyway. My nephew and his wife who live in Singapore both had Pfizer and both had reactions to their 2nd vax.
The reason why Astra Zeneca was given a bad reputation was that the UK scientists did not do the “wash up”, which means they didn’t collect the statistics on complications.
The first the world knew that this vaccine may have complications, is when Norway contacted the UK and Sweden scientists and asked for their data and they had NONE.
Norway cancelled their order and Australia should never had paid for a manufacturing plant in Australia for CSL without that data.
There was no excuse for such sloppy science.
Anecdotally, my husband had Astra Zeneca and suffered from the inability to think clearly for about 2 weeks.
The next problem he encountered was that the AZ vaccines only lasted 12 weeks and so, had to shield himself because the interval moved back to 12 weeks, the day prior to his 16 week booster shot of Moderna.
That was his reward for being an early compliant member of the medical field.
Ditto, Astra Zeneca affected my brain, my concentration levels dropped within the first 24 hours & remain diminished months later. Not to mention the constant tinnitus – a consequence which the manufacturers dismiss. However Johnson & Johnson now acknowledge tinnitus as a potential side effect for their Janssen vaccine (which is not available in Oz). I and three others of my acquaintance contracted tinnitus within days of the first AZ vaccine. Guy Rundle also mentioned it as a throwaway line in one of his pieces on an unrelated subject following his first jab.
Any measured discussion of side effects elicits accusations of being anti-vax. There seems to be no middle road for calm debate.
Two of the biggest side effects of covid-19 were: (1) the urge for individuals to generalise for the entire population based on their own experience [you mention sloppy science], and (2) the mistaken tendency to compare having the vaccine to not having a vaccine and not being infected [the only relevant comparison is with unvaccinated infection]. Nobody has yet suggested you will feel better simply by ingesting a vaccine.
I remember at one point the ABC News site had two separate headlines on the same day about AstraZeneca deaths, and another one about a potential suspected death where it was unknown whether the person in question had even had the vaccine. A clickbait media with very little to report on at the time (hard borders were still doing their job) whipped people up into a frenzy by taking each individual case as headline news.
These days we get “47 dead in Queensland from Coronavirus” instead of 47 different headlines detailing deaths. The media managed to take the statistically-unusual and turn it into a legitimate fear while making the more troubling statistics seems mundane. (And nothing to worry about because businesses are hurting and we need to open up, and stop wearing masks, and get rid of social distancing rules. People are sick of this, don’t you know?)
“The death of one man is a tragedy. The death of millions is a statistic.”
The saddest part of it all is that every problem, then became an anti-vaxxer’s dream.
I do still think that AZ was the rough and ready and killed some whilst saving a lot of others and was best superceded for effectiveness by the mRNA’s and now by the protein based NovaVax.
This whole thing boils down to the perceived versus the real risks as instanced by the polio vaccines of Salk and Sabin.
Don’t worry the next wave is coming and so is influenza, more needles.
Had AZ. Nothing happened except light headedness immediately after due to release of pent up anxiety due to information overload. I did however suffer a bleeding thrombotic haemorrhoid months later by being shafted by everyone’s thoughts on vaccines, COVID and governments.
The media tend to fall into line with the American ‘story’ on a depressingly regular and predictable basis.
Money keeps talking.