The six reported cases included more than 6.8 million doses of the Johnson & Johnson vaccine administered in the United States.
All six cases occurred among women between the ages of 18 and 48, and symptoms occurred 6 to 13 days after vaccination, according to a joint statement Tuesday from Dr. Anne Schuchat, chief deputy director of the CDC and dr. Peter Marks, director of the FDA’s Center for Biological Evaluation and Research.
“The CDC will convene a meeting of the Advisory Committee on Immunization Practices (ACIP) on Wednesday to further investigate these matters and assess their potential importance,” the statement said. “The FDA will review the analysis as it also investigates these cases. Until the process is completed, we recommend an interruption in the use of this vaccine out of abundance of caution. It is partly important to ensure that the healthcare provider community is aware of the potential for these side effects and can plan for proper recognition and management due to the unique treatment required for this type of blood clot. “
CNN contacted Johnson & Johnson for comment.
For people who have received the Johnson & Johnson shot, those who have developed severe headache, abdominal pain, leg pain or shortness of breath should contact their healthcare provider within three weeks after vaccination.
The statement also noted that these adverse events ‘seem extremely rare’.
“But I want to congratulate the CDC and the FDA for jumping in very quickly, stopping the vaccinations until we know more, and really trying to understand what’s going on,” del Rio said. “I think vaccine safety has always been a priority – and I think it’s exactly the right step until we understand what’s going on and what the road ahead is.”
The AstraZeneca vaccine is not used in the United States, but has been approved in more than 70 countries. The European Medicines Agency recently concluded that abnormal low blood platelet counts should be listed as ‘very rare side effects’ of the AstraZeneca vaccine. While advising the public to look at the signs of blood clots, regulators say the benefits of the shot are still worth the risk.
“The adenovirus vector vaccine may have something to do with it,” del Rio said. The other two Covid-19 vaccines allowed for emergency use in the United States – Pfizer’s and Moderna’s – are mRNA vaccines, which are of a different type.
He added that he still recommends that people be vaccinated against Covid-19.
Federal health channels stop using J&J vaccine immediately
According to a federal health official, the federal health channels – mass vaccination centers, community health centers and the like – that previously administered the Johnson & Johnson vaccine will be announced by the FDA and CDC. .
The agencies recommend that states do the same, but it is up to the individual states to make the decision because they are given a separate allocation of doses.
The break took place because this type of blood clot was not listed on the list of possible adverse side effects that were part of the emergency use authorization for J&J. While officials stress that it is rare, they want healthcare providers to have time to understand what the side effects are and how to best treat them.
The CDC and FDA made the decision late last night, a federal health official said.