Should we ditch AstraZeneca’s COVID-19 vaccine before it drags down the whole campaign?

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The European Union has decided AstraZeneca’s COVID-19 vaccine is no longer worth the bother. The EU will not renew its contract for June, opting instead to go all-in with Pfizer.

Should Canada follow suit?

AZ (which is in the news so often it now has its own shorthand) accounts for about 12 per cent of the vaccines administered in Canada – and about 99 per cent of the grief.

I got my first shot of the AstraZeneca COVID-19 vaccine. How do I know if I’m at risk of developing a rare blood clot?

Much of the talk about AZ revolves around the potential risk to individuals developing a rare blood-clotting syndrome, vaccine-induced thrombotic thrombocytopenia.

VITT is rare. So far, among the 2.3 million AstraZeneca doses administered in Canada, there have been 12 recorded cases, including three deaths. Depending on whose expert math you believe, the risk of VITT ranges anywhere from 1 in 26,000 to 1 in 250,000.

Pfizer and Moderna don’t have that “safety signal.” If all vaccines are equally effective – and that’s a subject of debate too – then why would we bother with one that poses risks, however minimal?

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The obvious answer is that we want to get as many people vaccinated as quickly as possible. There’s no question that getting COVID-19 is a much greater risk than getting a vaccine. But what happens if, because of their fears (legitimate or otherwise), people don’t get vaccinated at all?

If AstraZeneca’s woes are creating vaccine hesitancy, and we have alternatives available (like two million Pfizer doses rolling in weekly) then is it worth having it on offer?

There are a lot more questions here than answers. We’re all trying to do complex risk-benefit calculations – individually/collectively, and politically/scientifically – with ever-shifting variables.

To date, Canada has administered 18 million vaccine doses. We’ve plucked much of the low-hanging fruit. The rollout will only get more challenging as we reach out to greater swaths of the population.

That’s why it’s increasingly essential that there be no doubts about vaccine efficacy or safety. And it’s why clear communication is so important.

“All vaccines are equally effective” and “take whatever vaccine is offered” are good, clear public health messages.

But those messages are getting harder and harder to believe.

The National Advisory Committee on Immunization, an independent group of experts responsible for drafting national guidelines, now says that AstraZeneca vaccines should be taken by… well, who the hell knows?

The advice has changed so often that nobody knows what the advice is anymore.

NACI’s “Recommendations on the use of COVID-19 vaccines” is more than 110 pages long, full of head-spinning nuance. To make matters worse, NACI’s public statements are downright perplexing. It says mRNA vaccines (Pfizer and Moderna) should be “preferentially offered,” which suggests they are better than adenovirus vaccines (AstraZeneca and Johnson & Johnson) – which is very different from public-health messaging.

Depending where you live in Canada, AstraZeneca is being offered to those over 30 or 40 years of age. The logic here is that the younger you are, the lower your risk of serious harm from COVID-19, meaning the relative risk of suffering harm from VITT is greater.

NACI says people over 30 can take AZ or the Johnson & Johnson vaccine “if they do not wish to wait for a mRNA vaccine” (not exactly an enthusiastic endorsement), and they should do an “individual risk assessment.” But doesn’t say how. Humans are pretty bad at judging risk at the best of times, and even less so when they are caught in a twister of conflicting information.

If you aren’t already sufficiently confused about the pros and cons of AZ vaccination, just pay a visit to Twitter, where experts relentlessly drop fiery hot takes. This kind of discussion is normal in science, but in the public realm it’s off-putting at best.

Bottom line: We’re left with the perception that AstraZeneca vaccine is second-rate. In the public/political realm, perception matters more than science, especially when you’re trying to vaccinate 38 million people.

Those who rushed out to get the AstraZeneca vaccine (mostly GenX-ers, who are the most ardent vaccination supporters) are feeling burned. They are left with the impression that decisions have been driven more by supply issues than science.

When supplies of Pfizer and Moderna were running low and the U.S. had AstraZeneca vaccine that was about to expire, suddenly AZ was being highly touted.

In retrospect, it has an “eat the stuff at the front of the fridge before it goes bad” feel to it.

Perhaps it’s time to clean out the vaccine fridges, to stick with Pfizer and Moderna, and stop trying foist AZ on people when it is looking increasingly unpalatable.

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