Use of the Johnson & Johnson COVID-19 vaccine remains on hold in the United States as officials gather more information about the rare blood clots reported in six people who received the injection. An independent advisory committee from the Centers for Disease Control and Prevention said it did not yet have enough information to say which groups may be at risk for the clots or to recommend who should receive this vaccine.
“I don’t think we have enough information today,” Grace Lee, associate chief medical officer for practice innovation at Lucile Packard Children’s Hospital in California, said during Wednesday’s committee meeting. The group will meet again as soon as possible – probably next week – after gathering more data and evaluating that information.
The Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) recommended Tuesday morning that the US should stop using the Johnson & Johnson vaccine in light of six reports of unusual blood clots in people who received the injection. While there is no proven relationship between the clots and the vaccine, and the events are likely to be rare, the authorities wanted time to examine the reports and provide doctors with information on how to treat the condition. The agencies said on Tuesday they hoped to resolve the break as soon as possible.
Disadvantaged communities in the US are most affected by a Johnson & Johnson break. The easy-to-store, single-use vaccine has been used on home-bound seniors, in rural pop-up clinics, and those who were homeless. The effect of this pause on those groups was a serious topic of discussion at today’s meeting. “This one-time vaccine that didn’t require the cold chain is a significant loss,” said Camille Kotton, the clinical director of transplantation and immunocompromised infectious diseases at Massachusetts General Hospital. However, that group could have the most challenges of getting treatment for a clot if they develop one, noted Helen Talbot, an associate professor of medicine at Vanderbilt University.
The CDC received the six reports between March 19 and April 12 through the Vaccine Adverse Event Reporting System (VAERS). Unusually, all six patients had cerebral sinus venous thrombosis (a type of blood clot in the brain) in combination with a low platelet count, a type of blood cell involved in clotting.
The CDC paid special attention to reports of these clots because of the problems with the AstraZeneca vaccine in Europe and the UK, Tom Shimabukuro, a member of the CDC’s COVID-19 Vaccine Task Force, said during the committee meeting. “This is a really good example of how robust the US vaccine safety control system is and how in this case, during a large-scale national mass vaccination program, the system worked in several functions as planned,” he said.
The COVID-19 working group of the CDC’s Advisory Committee on Immunization Practices (ACIP) met earlier this week to discuss the reports. The six people who had blood clots were all young women. Although rare, they occurred more quickly than expected in that group.
Sara Oliver, an epidemic intelligence officer at the CDC, said During today’s meeting, the working group noted how much we still don’t know about these clots. It is not clear how common the combination of both the clots and the low platelets normally occurs in the general population, making it difficult to say how far above the norm these reports are. We also don’t have a good idea of the risk factors for developing this condition. There could be further reports as well – nearly 4 million people have received doses in the past two weeks, and those people are still in a window where a clot can form.
The group also noted that the Johnson & Johnson vaccine isn’t the only shot available in the US. Officials don’t see the same problems in people who have received the Pfizer / BioNTech or Moderna vaccines. Only about 5 percent of the vaccines given in the US to date have been the Johnson & Johnson injection.
“We are very lucky because we have several other alternatives in the US to end the health pandemic,” said Talbot. “We are in a different position and can be more careful.”