Rare Blood Clots Linked to J&J and AstraZeneca Vaccines Caused by Autoimmune Reaction
Researchers have discovered that the rare but deadly blood clots associated with the Johnson & Johnson and AstraZeneca Plc's Covid-19 vaccines are caused by an autoimmune reaction that some people are predisposed to. This finding is expected to significantly impact the development of future vaccines.
The study, published in the New England Journal of Medicine, revealed that adenovirus-based vaccines, like the J&J and AstraZeneca shots, contain a component that can trigger blood clots in people who are genetically susceptible. Researchers plan to identify the culprit and then try to remove it using genetic engineering.
The exact number of people susceptible to this complication is unknown. However, the immune reaction linked to the shot is considered a "new disease." As healthcare professionals become more familiar with these conditions, more cases are likely to be identified.
Out of more than 18 million people who received the single-dose J&J vaccine, 60 cases of the clotting disorder were reported, and nine people died. A small number of clot-related deaths tied to the AstraZeneca vaccine led to its withdrawal or restriction in several countries.
Both companies, J&J and AstraZeneca, have expressed support for further research to understand the underlying mechanism of this rare event and guide the development of safer and more effective vaccines.
While both vaccines played a crucial role in vaccination programs during the early stages of the pandemic, the mRNA vaccines developed by Pfizer-BioNTech and Moderna have proven to be more effective at protecting against Covid-19 and have been updated to tackle newer virus variants.