WRAL Investigates

Expert: Risk of blood clots from vaccine much less than from COVID without it

Data show serious side-effects from the Johnson & Johnson vaccine are extremely rare: 6.7 million doses have been administered, the six women are the only cases reported so far.

Posted Updated

By
Joe Fisher
, WRAL reporter
RALEIGH, N.C. — Federal health officials recommended a pause in the distribution of the Johnson & Johnson coronavirus vaccine after six women reported with a rare blood-clotting disorder following their shots.

One of those women died, and a second is hospitalized in critical condition.

"I’m not 100 percent surprised," Pia MacDonald, an epidemiologist with RTI International in Research Triangle Park, said of the halt. "In fact I think it’s a wise and prudent thing to do."

The pause offers health experts a chance to tackle a lot of questions, most importantly whether the vaccine is the main reason the women contracted cerebral venous sinus thrombosis, along with abnormally low platelet counts, MacDonald said. It also allows providers to learn more about the signs and symptoms of CVST so they can advise vaccine recipients.

MacDonald said she doesn’t believe the shortened timeline for vaccine trials played a role in the side-effect. The trials involved about 30,000 participants, so the likelihood of finding it during trials was extremely low, she said.

Data show serious side-effects from the Johnson & Johnson vaccine are extremely rare: 6.7 million doses have been administered, the six women are the only cases reported so far.

Less serious clotting reactions have been reported with all three of the available vaccines, but again, the chances are small.

WRAL Investigates searched through tens of thousands of adverse reaction reports. Nationally, Pfizer has reported 147 incidents of thrombosis, Moderna 100 and Johnson & Johnson only 14. Of all of those cases, only six are in North Carolina.

But based on doses administered, the script flips, and Johnson & Johnson has the highest number of clotting reactions, with 20 per 100,000 doses. Pfizer is next with 15 per 100,000, followed by Moderna with 12.

MacDonald said any vaccine is better than the alternative.

"If you’re a 55-year-old person, your risk of dying from COVID-19 is much, much, much higher than an adverse reaction to the vaccine itself," she said.

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