No blood clot cases linked with Moderna and Pfizer coronavirus vaccines, CDC expert says By CNN’s Maggie Fox Published Apr 24, 2021 1:21:38 AM enablePagination: false Courtesy: Chip Somodevilla/Getty Images (CNN) — No blood clots have been associated with coronavirus vaccines made by Moderna or Pfizer, a US Centers for Disease Control and Prevention expert said Friday. The CDC’s Advisory Committee on Immunization Practices is meeting to discuss whether to change guidance for J&J’s Janssen vaccine. The CDC and the US Food and Drug Administration recommended pausing its use after six reported cases of women who developed a rare blood clotting syndrome called thrombosis with thrombocytopenia syndrome, or TTS, after receiving Johnson & Johnson’s Janssen vaccine in the United States. But no cases have been firmly linked with other vaccines used in the US.