The nationwide pause on the Johnson&Johnson vaccine will continue for at least another week.
After the CDC and FDA recommended a pause on Johnson&Johnson vaccinations Tuesday, a federal advisory panel met virtually Wednesday afternoon to discuss whether states could resume.
The agencies made the recommendation after six women all between the ages of 18 and 48 developed a rare type of blood clot within two weeks of receiving the single-dose vaccine.
The CDC's Advisory Committee on Immunization Practices said more information on the rare side effect is needed before moving forward.
"Basically, you know to be very frank, I do not want to vote on this issue today," advisory council member Dr. Beth Bell said.
The panel of outside experts had two things to consider: did they have enough information to once again recommend the use of the J&J vaccine and what recommendation would be appropriate?
Many committee members said they did not feel there was enough data to make and evidence-based vote on that.
"While causality has not been fully established between these rare events and our vaccine, we recognize these events could represent an important potential risk with the Janssen vaccine," said Dr. Aran Maree, chief medical officer of Johnson&Johnson's Pharmaceuticals.
The rare blood clots are similar to those tied to the AstraZeneca vaccine, which is still not approved for use in the U.S.
"In the European cases, both men and women presented with the blood clots, though they were more frequent in women," CDC Director Rochelle Walensky said.
Federal health officials stress these cases are extremely rare -- only six out of more than 6.8 million doses administered.
"We do need to better understand the risk which we know is going to be very rare, very low but we really don't know exactly how low and how to correctly characterize it," Dr. Bell said.
Anyone who received the J&J vaccine within the past month should be aware of the signs of the rare blood clot, including severe headache, difficulty moving, leg or abdominal pain and shortness of breath.
For the time being however, health leaders say there is plenty of Pfizer and Moderna supply to continue vaccinations.
The advisory committee plans to meet again and discuss next steps within 10 days.