On April 12, more than 6.8 million doses of Johnson & Johnson (Janssen) vaccine were administered to the U.S. CDC and the FDA reviewed data involving six reported U.S. cases of a rare and severe type of blood of individuals after receiving J&J Vaccine. In these cases, a type of blood clot called cerebral venous sinus thrombosis (CVST) is found to be associated with low levels of blood platelets (thrombocytopenia). All six cases occurred in women aged 18 and 48, and symptoms occurred 6 to 13 days after vaccination. The treatment of this specific blood type is very different from the treatment that can usually be given. Typically, an anticoagulant medication called heparin is used to treat blood clots. In this case, heparin administration can be risky, and alternative treatments should be provided.
The CDC will convene a meeting of the Advisory Committee on Immunization Practices (ACIP) on Wednesday to further examine these cases and assess their potential significance. The FDA will review that analysis because it is also investigating these cases. Until that process is complete, we recommend stopping using this vaccine out of extreme caution. This is important, in part, to ensure that the health care community is aware of the potential for adverse events and can plan for proper identification and management due to the unique treatment required for this blood type.
Today, these unfortunate events appear to be even more remarkable. The safety of the COVID-19 vaccine is a top priority for the federal government, and we take seriously all reports of health problems following the COVID-19 vaccination People who have received the J&J vaccine who experience severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their healthcare provider. Health care providers are asked to report adverse events to the Vaccine Adverse Event Reporting System at https://vaers.hhs.gov/reportevent.htmlexternal icon.
The CDC and FDA will provide more information and answer questions later today in a media briefing. A recording of that media call will be available on the FDA’s YouTube channel.