As of Monday, more than 6.8 million doses of the Johnson & Johnson vaccine had been administered in the United States.
But six reported cases of what the Centers for Disease Control is calling a rare and severe type of blood clot has the CDC and the U.S. Food and Drug Administration calling for a pause in the administration of the vaccine.
Dr. Anne Schuchat, principal Deputy Director of the CDC, and Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, issued a joint statement Tuesday calling for the pause.
In their statement, the doctors said a type of blood clot called cerebral venous sinus thrombosis was seen in combination with low levels of blood platelets. All six cases occurred among women between the ages of 18 and 48, and symptoms occurred 6 to 13 days after vaccination, according to the statement.
According to the statement, the CDC will convene a meeting of the Advisory Committee on Immunization Practices Wednesday to further review these cases and assess their potential significance. The FDA will review that analysis as it also investigates these cases.
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“Until that process is complete, we are recommending a pause in the use of this vaccine out of an abundance of caution,” the doctors said in the joint statement. “This is important, in part, to ensure that the health care provider community is aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required with this type of blood clot.
The federal health agencies said Tuesday morning that “treatment of this specific type of blood clot is different from the treatment that might typically be administered” for blood clots.
“Usually, an anticoagulant drug called heparin is used to treat blood clots. In this setting, administration of heparin may be dangerous, and alternative treatments need to be given,” the statement said.
Johnson & Johnson officials said in a news release they’re “aware that thromboembolic events” have “been reported with COVID-19 vaccines.”
“At present, no clear causal relationship has been established between these rare events and the … Covid-19 vaccine,” they said.
In their joint statement, Schuchat and Marks said COVID-19 vaccine safety “is a top priority” for the federal government.
“We take all reports of health problems following COVID-19 vaccination very seriously,” they said.
People who have received the J&J vaccine who develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider.
