What the hell is going on with the Oxford-AstraZeneca vaccine?

The problem child of COVID-19 vaccines was back in the news this week. After South Africa suspended the Oxford-AstraZeneca vaccine’s use when it failed to slow the spread of the predominant B.1.351 variant, vaccination using this vaccine has been suspended and then resumed in many European countries following reports of blood clots in some people who received it. 

According to a release from AstraZeneca, there have been 15 cases of deep vein thrombosis and 22 cases of pulmonary embolism in people who have gotten the vaccine, as of March 8. These are serious complications—seven of those people died. Countries that suspended the vaccine’s use include Spain, Italy, France, and Germany, among others. (Europe tends to act as more of a bloc than North America when it comes to vaccines. Consider: Canada has authorized use of the AstraZeneca vaccine while the US has literal fridges full of the stuff just sitting there waiting for approval.)

Since the initial suspension, investigations have been launched and apparently concluded that there is no causative relationship between the vaccine and these symptoms. According to Emer Cooke, the executive director of the European Medicines Agency (EMA), in a press conference on March 18: “The committee… concluded that the vaccine is not associated with an increase in the overall risk of thromboembolic events or blood clots.”

And, according to the WHO on March 17: “At this time, WHO considers that the benefits of the AstraZeneca vaccine outweigh its risks and recommends that vaccinations continue.” Europe has since started to resume vaccinating with the Oxford-AstraZeneca vaccine, starting with France, Germany, and Italy. (Except not in Finland, where they just suspended it again after two people got similar blood clots.)

So all’s well that ends well right? Well, not necessarily. Besides that Finland wrinkle, some scientists and officials are concerned that this entire rigmarole could undermine public trust in the AstraZeneca vaccine. It’s worth noting that a tiny population experienced these effects out of the millions of people who have already gotten the vaccine. And blood clots are fairly common in the population; you’re going to expect some people to develop them just by sheer chance. But it’s also worth noting that these complications are serious, and rare among the age group that they were reported in. Not slowing down could have the same fear-inducing effect. As Shobita Parthasarathy says in her Slate column, “[T]his crisis isn’t about science at all. It’s about public trust, and scared citizens cannot be easily convinced by expertise that feels remote. Our solutions need to reflect that.”

We’ll see if anything else happens. But in the meantime, the US has since promised to share its stockpile of the Oxford-AstraZeneca vaccine with Canada and Mexico, so it looks like it’s at least medium-steam ahead for now. 

In summation:

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