European Regulators Determine Link Between AstraZeneca's COVID-19 Vaccine And Blood Clots

European regulators have determined there is a link between AstraZeneca's COVID-19 vaccine and clotting. KDKA's Dr. Maria Simbra has more.

Video Transcript

- After weeks of speculation, European drug regulators now say there is a possible link between AstraZeneca's COVID vaccine and blood clots.

- Dr. Maria Simbra examines how common it is and if any of the other vaccines share the same risk.

MARIA SIMBRA: European regulators have determined there is a link between AstraZeneca's COVID-19 vaccine and clotting by looking at the numbers.

MARC ITSKOWITZ: Normally, there's about two to four of these cases out of every million people. And when they looked at the patients who were vaccinated, that number was about six cases per million. And so even though that's a small increase, it did get their attention.

MARIA SIMBRA: The type of blood clot linked to this particular vaccine is very rare. These occur in the veins of the brain and the abdomen.

MARC ITSKOWITZ: The vaccine may be stimulating an unusual type of antibody that is related to this type of blood clots.

MARIA SIMBRA: Researchers are still trying to figure out why the clots are happening. 18 cases have been fatal.

MARC ITSKOWITZ: The concern regarding blood clots is limited to the AstraZeneca vaccine. It is true that J&J also uses a virus-vector technology. But keep in mind, J&J has used this technology with other vaccines in the past. And we haven't seen this type of complication.

MARIA SIMBRA: The regulators in Europe, say the unusual clots with levels of certain blood cells being low should be listed as a side effect. They also stress that the benefits outweigh the risks. The two-dose immunization is 76% effective at preventing illness with COVID.

Some countries are already limiting the AstraZeneca vaccine to older people, since most of the clots have been in people younger than 60.

MARC ITSKOWITZ: It does appear to be more of a concern in the young people where the benefit from the vaccine may not be as great as it is in the older population.

MARIA SIMBRA: The AstraZeneca product costs $4 per dose compared to 10 to 40 for the others. And it can be refrigerated. Nevertheless, Dr. Itskowitz does not expect emergency use authorization on the horizon.

MARC ITSKOWITZ: We are now vaccinating four million patients a day using J&J. Moderna and Pfizer. I think we should stick with these three vaccines for now.

MARIA SIMBRA: He says as we continue to vaccinate millions, rare complications like these clots will become more evident. I'm Dr. Maria Simbra, KDKA News.