What's going on with AstraZeneca?
You may have heard the news from Europe regarding their COVID vaccine roll-out. Many countries paused administration of the AstraZeneca COVID-19 vaccine after reports of blood clots in several patients who received the vaccine. There’s a lot of information out there about what is going on, so I’m going to try to break it down here.
What are the facts?
Blood clots have been reported as a side effect of the AZ vaccine
Of the 17 million people in the EU/UK that have received the vaccine, 40 cases of blood clots have been reported
Per year, it is estimated that 1 in 1000 people suffer from blood clots in the U.S.
It is estimated that 1000-2000 blood clots occur in the U.S. daily
2 patients in Norway, 1 in Denmark, and 1 in Italy have died after receiving the AZ vaccine, though it is unclear if the vaccine was the actual cause of death
In clinical trials for the AZ vaccine, the incidence of blood clots was lower in the vaccination group than in the control group
What have authorities said about it?
The WHO believes that the benefits of the vaccine outweigh any risk, given that the incidence of blood clots is low
The European Medicines Agency (EMA), after a thorough investigation, deemed the vaccine safe and effective, claiming that the rate of blood clots seen post vaccine is lower that the expected rate in the general population
A group of German scientists analyzed 13 cases of the blood clots for possible ties to the vaccine. They believe a possible link is the overactivation of the immune system in response to the vaccine causing overactivation of platelets (necessary for regular blood clotting in the body). Given the small size of this study, this is solely a theory for now.
In other news:
In the U.S. trial, the AZ vaccine was shown to be 79% effective against symptomatic COVID infections, and was 100% effective at preventing severe disease
The trial also showed no increase in blood clots as a result of the vaccine
AZ is preparing to apply for EUA from the FDA soon, but it is unclear whether the U.S. will even need these doses