Over the last week, several countries stopped administering the Oxford/AstraZeneca Vaccine in Europe over 37 cases of "thromboembolic events" – or blood clots – that in some cases have been fatal. The cases happened in people who had recently received the vaccine, but there is currently no evidence suggesting that the vaccine caused these conditions and deaths.
The European Medicine Agency’s Pharmacovigilance Risk Assessment Committee (PRAC) began an investigation last week and the results will be published on Thursday, March 18, and in a press conference on March 16. The director of the agency, Emer Cooke, stated that so far there’s no indication that there a link between blood clots and the vaccine, and the benefits of the vaccine far outweigh potential risks.
The team at Technology Networks sat down with Dr Andrew Preston, a reader in Microbial Pathogenesis at the University of Bath, who in a video interview discussed the vaccine, its suspension by part of some European governments, and the dangerous and maybe deadly consequences of stopping the vaccinations.
“In their view, they are doing the right thing in terms of trying to reassure people that they are going to look into this, and then hopefully press play on that vaccination program once they've discovered, hopefully, that there is nothing to link any of these events with the actual vaccine itself,” Dr Preston explained in the interview.
Preston does a good job of clarifying the complexities of this situation from a medical point of view. There are just tens of cases of thrombosis among the 17 million doses of the vaccine already administered. In absolute terms, these numbers are in line with the general population, but the concern was about a particular type of blood clotting known as cerebral venous thrombosis or CVST.
Germany has stated that seven people out of 1.6 million vaccinated individuals over six weeks had CVST. The incidence of this condition is usually given at about five every one million people per year. Some revised estimates suggest that the real number is closer to 15 people per million. In either scenario, the incidence of this condition is higher.
An anomaly could be there, and the PRAC will soon report on this. That said, we need to consider the relative risk. The mortality of COVID-19 in the general population is around one in a thousand. For these blood clotting events, the mortality is closer to one in a million.
“There is no medicine or medical intervention – there is no process – that is absolutely risk-free, and I think we need to be utterly transparent about that,” Dr Preston explained. “It's about the sort of cost-benefit analysis.”
It is also important to realize that the decisions are not about science alone. They are social and political as well, especially in countries where vaccine hesitancy has been stoked over the last few decades. Political leaders and newspapers have previously misreported the efficacy of the vaccine, resulting in concerns regarding this vaccine in the general population. And that’s the challenge facing Europe once – rather than if – the vaccine is started again.
“I think those countries are going to have a very, very hard job of getting significant uptake with the Oxford/AstraZeneca vaccine over the next period,” Dr Preston explains.
With the number of COVID-19 cases increasing throughout Europe and a vaccination program that continues to slog, the pause is likely to translate to thousands of new cases of COVID-19 and related deaths.
You can check the full video below.