Here’s what to know about the risk of blood clots and the AstraZeneca vaccine

Here’s what to know about the risk of blood clots and the AstraZeneca vaccine

 

The UK's medicines regulator has said that at least 30 people in the United Kingdom have experienced rare types of blood clots after receiving the Oxford-AstraZeneca vaccine, but warned it was too early to know whether the shot itself triggered the clots.   The Medicines and Healthcare products Regulatory Agency has advised the UK continue administering the vaccine in all groups, arguing that such clotting incidents are very rare and that the benefits still greatly outweigh the risks, echoing similar assessments by the European Medicines Agency and the World Health Organization.   Looking at the benefits, since the UK started vaccinating people on December 7 up until March 21, there have been 30 cases of rare blood clots -- four of which were fatal. In that same time period, more than 2.5 million people caught Covid-19, and 63,082 people in the country died from the virus, government data show.   "It is vital that the vaccination rollout is not delayed," said David Spiegelhalter, chair of the Winton Centre for Risk and Evidence Communication at the University of Cambridge.   As far as risks go, looking into the incidence of blood clots is important. Blood clots in general are so common that it is expected that a certain number of people will get them for various reasons at any given day of any given week. If someone has had a vaccine and then develops a blood clot, it doesn't necessarily mean the shot caused the clot.   To get a clearer picture, scientists are looking more specifically at the types of clots being reported. CVST is rare to begin with, and normally, working out whether the incidence of a blood clot event has risen isn't difficult. In this case, however, it's a little murky, partly because the rate of CVST in the population isn't clear in the first place.