Local health experts react to federal recommendation to ‘pause’ use of J&J vaccine

"I know lots of folks think this will cause more vaccine hesitancy — and more harm than good. I'm honestly not so sure."

Vials of the Johnson & Johnson vaccine in California. David Paul Morris / Bloomberg

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Local public health experts had mixed reactions to the federal government’s move Tuesday to recommend a “pause” of the use of Johnson & Johnson’s one-shot COVID-19 vaccine after a half dozen women experienced a rare but severe type of blood-clotting, even if cases were less than one in a million.

“Glad to see safety prioritized, even for incredibly rare events,” MassHealth medical director Lakshman Swamy tweeted, adding that the vaccine “still seems overwhelmingly safe” and effective against preventing hospitalization or death due to COVID-19.

“Many of us are caring for young people with severe COVID and see the benefits in front of us,” Swamy wrote. “If available, I would still get this shot.”


In a joint statement Tuesday morning, the U.S. Food and Drug Administration and Centers for Disease Control and Prevention recommended the pause in the use of the J&J vaccine “out of an abundance of caution,” as officials review data involving six cases where women who received the vaccine experienced a unique type of blood clot. The six reported cases are out of more than 6.8 million overall doses of the one-shot vaccine administered in the United States.

Massachusetts subsequently ordered local vaccine providers to “immediately” pause administration of the J&J vaccine. Federal officials say the pause will help ensure that the health care community is “aware of the potential” of the type of blood clot, known as cerebral venous sinus thrombosis, which was similarly observed in rare cases associated with the AstraZeneca vaccine. According to the FDA and CDC, the pause also aims to ensure providers “can plan for proper recognition and management” since treatment differs from other types of blood clots.

The recommendation is the second recent setback for the one-shot vaccine, which officials have touted for its ease of storage and delivery relative to the two-shot Pfizer and Moderna vaccines. States have already been adjusting to a dramatic decrease in J&J supply for the next few weeks due to a manufacturing issue. While officials continue to distribute and administer millions of the Pfizer and Moderna vaccines, the timing also comes just as states are expanding vaccine eligibility to all adults.


In addition to hampering supply, the FDA and CDC’s announcement Tuesday also elicited an outpouring of concern that the “pause” would discourage individuals from getting vaccinated, despite the rarity of the blood-clotting cases.

“Vaccine hesitancy is biggest problem in US going forward,” tweeted Dr. Joseph Allen, an associate professor at Harvard University’s Chan School of Public Health. “And I know we really, really, REALLY, want to believe the public will see this as ‘the system is working!’ but the reality is they will see it as another caution flag on vaccines.”

Others were less sure of the implications, but stressed the importance of taking even rare events seriously.

Dr. Ashish Jha, the dean of Brown University’s School of Public Health, said Tuesday that the federal government’s recommendation was “unfortunate,” but the “right step.”

“Confidence is built on having a system that takes adverse events seriously, investigates them, makes data-driven decisions,” Jha tweeted Tuesday morning.

“I know lots of folks think this will cause more vaccine hesitancy — and more harm than good,” he said. “I’m honestly not so sure. My sense is confidence comes from people believing that we have a vigorous system that takes adverse events seriously.”

Dr. Megan Ranney, director of the Brown Lifespan Center for Digital Health, noted in a series of tweets that research has suggested those infected with COVID-19 itself have a much greater chance of experiencing blood clots. However, given that all six reported cases of cerebral venous sinus thrombosis affected women between the ages of 18 and 48 who had gotten the J&J vaccine, Ranney said the risk calculation may be different depending on the individual.


“Science and medicine, like life, is full of weighing risks vs benefits,” Ranney tweeted. “Right now, the risk of catching #covid19 & getting a bad complication is much higher than this very rare adverse effect. BUT – for some groups (women? Young women?) that assumption may not be true.”

Still, she added that what is “INDUBITABLY true right now” is that COVID-19 cases have again begun to rise in the United States and across the world, and that the J&J vaccine has proven overwhelmingly effective at preventing complications due to the disease.

Ultimately, Dr. Maimuna Majumder, a faculty member of Harvard Medical School and Boston Children’s Hospital, said it’s incumbent on experts to properly communicate and contextualize the situation.

“This is the process at work; our job is to relay that to the public,” Majunder said.


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