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Rare blood clots following both the AstraZeneca and J&J vaccines might be no coincidence — they share the same technology
The AstraZeneca and Johnson & Johnson shots are both viral vector vaccines. Both have been linked to cases of rare blood clots in the brain.
By Aria Bendix
When coronavirus vaccines were rolled out to the public, regulators knew they would need to watch out for extremely rare reactions. Although clinical trials had shown the shots to be safe among tens of thousands of people, the world was about to vaccinate tens of millions.
Their vigilance paid off earlier this month when European regulators announced that rare blood clots might be an uncommon side effect of AstraZeneca’s vaccine. Then on Tuesday, US regulators recommended a pause in the distribution of Johnson & Johnson’s vaccine due to six reports of the same type of clot among women who’d received that shot.
AstraZeneca’s and J&J’s vaccines share a platform: Both are viral-vector vaccines, which introduce a coronavirus gene into the body using a genetically engineered common-cold virus, called an adenovirus. Some medical experts are now wondering whether that technology itself could be linked to clotting.
“Why are we seeing these few cases for J&J and AstraZeneca? We don’t know. It just…
