Pause of Johnson & Johnson vaccine will continue as expert panel seeks time to study safety data

A CDC advisory panel recommended Wednesday to continue the pause on the use of the Johnson & Johnson vaccine until it has more time to study the safety data on the single-dose vaccine.

This means the hold on the vaccine in the US could continue for another two weeks.

The Advisory Committee on Immunization Practices (ACIP) members agreed to take up the question of whether to recommend additional safety guidance about who should receive the vaccine at its next meeting in early May.

The nationwide pause caught Lauren Vogelbaum in Atlanta off-guard.

Vogelbaum got the Johnson & Johnson vaccine late Monday afternoon at a local doctor's office.

After months of waiting for shot , she says, it was a big moment.

"It was just such a joy and relief," she says.  "The nurse and I were chatting, and she handed me the little card, and I was like, 'Ah!'"

Tuesday morning, the 38-year-old science podcaster  woke up to the news the CDC and FDA had halted the distribution of the J&J vaccine to investigate 6 cases of rare blood clots in women under the age of 50 who received the vaccine.

Vogelbaum, who says she experienced cold-like symptoms and brain fog the morning after her vaccination, but no other complications, says she was surprised by the pause.

"I understand why they wanted to pull the vaccine until they have a better grip on what's causing these very infrequent reactions," Vogelbaum says.  'But, at the same time, I'm not personally concerned."

Health experts say 6 women between the ages of 18 and 48 developed a rare type of blood clot in their brains known as a cerebral venous sinus thrombosis (or CVST) within 6 to 13 days of receiving the Johnson & Johnson vaccine.

The women also all had low platelets, the cells in the blood that allow it to clot.

Officials say the combination of this type of clot and low platelets is unusual, and typically not seen in younger, healthy people.

Only one of the 6 women was using oral birth control, which can raise the risk of blood clots.

One woman died, 2 were released from the hospital and 3 remain hospitalized.

CDC Director Dr. Rochelle Walensky says 7.2 million people have received the Johnson & Johnson vaccine.

"Right now, we believe these events to be extremely rare," Dr. Walensky says.  "But, we are also not yet certain we have heard about all possible cases, as this syndrome may not be easily recognized as one associated with the vaccine."

The CDC and FDA are alerting health care providers and vaccine recipients to be aware of the situation and watch for severe headache, abdominal or leg pain, and shortness of breath, all signs of CVST, in vaccine recipients coming into emergency departments.

The agency is also warning doctors who to avoid using the blood thinner heparin to treat this combination of clots and low platelets, because the drug can exacerbate the problem.

Four of the 6 women were treated with heparin.

"CDC and FDA are working rapidly to investigate each case and understand whether there is a causal relationship between these blood clots and vaccine administration," Dr. Walensky says.

The CDC's advisory panel spent Wednesday afternoon reviewing the safety data for the vaccine.

The 6 US cases resemble 169 reports in Europe of blood clots in people who have received the AstraZeneca vaccine, which uses a similar technology to the Johnson & Johnson vaccine. Both are adenovirus vector vaccines.

The advisory panel noted the US has two authorized COVID-19 vaccines, made with a different technology, the Moderna and Pfizer vaccines, that have not been associated with blood clots.

Those two vaccines make up more than 90% of US COVID-19 vaccinations distributed so far.

Back in Atlanta, Lauren Vogelbaum says she will be watching for complications, but she has no regrets about getting the single-dose Johnson & Johnson vaccine.

"I would do it again," Vogelbaum says.  "I'm just always so happy to get a vaccine."

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