Prognosis

AstraZeneca Shot Brings No Increased Blood-Clot Risk After Two Doses

  • Rate of disorder after second shot was same as in unvaccinated
  • U.K. regulator reported 411 cases of clots including 71 deaths
Photographer: Dimas Ardian/Bloomberg
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AstraZeneca Plc’s Covid-19 vaccine doesn’t raise the risk of a rare blood clotting disorder after a second dose, suggesting people shouldn’t hesitate to get another one if they didn’t have trouble after the first.

The estimated rate of the disorder, called thrombosis with thrombocytopenia syndrome, was 2.3 per million in people who received a second shot, according to data published in the medical journal The Lancet. That’s comparable to what’s found in an unvaccinated population. But the rate after a single dose was still higher, at 8.1 per million.