The break in the Johnson & Johnson Covid 19 vaccine should last for days, not weeks, according to CDC and FDA officials.
In 37 minutes online briefing On Tuesday, government health officials said stopping the administration of the J&J vaccine will give scientists time to investigate what appears to be an autoimmune response that leads to cerebral venous sinus thrombosis, an extremely rare and stroke-like reaction.
With more than 6 million doses of the J&J vaccine administered to date, six cases of CVST are known. All occurred in women aged 18 to 48 years. One woman is dead and another is in critical condition.
CVST is uncommon and affects five people in a million, according to Johns Hopkins Medicine. However, J&J cases are even rarer because they are accompanied by a low platelet count, according to Peter Marks, MD, PhD, panel member and director of the FDA Center for Biologics Evaluation and Research.
“Right now, these events seem to be extremely rare,” Dr. Marks said. “That said, the safety of the Covid-19 vaccine is a top priority for the federal government and we take all post-vaccination events very seriously.”
In the reported cases, the adverse reaction occurred 6 to 13 days after receiving the J&J vaccine. Acknowledging that the break would worry people who have received it, Anne Schuchat, MD, a panel member and CDC chief executive, tried to calm the fears.
“For people who received the vaccine more than a month ago, the risk for them is very low right now,” Dr. Schuchat said. “For people who recently received the vaccine in the last two weeks, they should be aware of looking for any symptoms.”
These symptoms include severe headache, abdominal pain, leg pain, or shortness of breath. Anyone who has any of these symptoms should contact their doctor immediately. Dr. Schuchat added that the CDC has had no reports of low platelet counts in the more than 190 million people who received the Pfizer / BioNTech or Moderna vaccines. Both vaccines use the new mRNA technology. The J&J vaccine uses an adenovirus.
The independent advisory committee on CDC immunization practices was expected to begin reviewing data from the J&J case on Wednesday to consider the next step. Meanwhile, officials will warn doctors about symptoms and how to treat affected patients.
“We are committed to following science and ensuring transparency and providing regular updates,” Drs. Schuchat. “We will tell you what we know when we know it and what you can do to protect yourself. Our intention is to update it in the coming days. “
While no one is sure what causes the rare reaction, a fundamental theory, Dr. Marks said, is that an immune response activates platelets that leads to clotting and a stroke-like reaction. Similar cases of blood clotting have been reported in Europe with the AstraZeneca vaccine. In these cases blood clots form in the gastrointestinal system.
Robert Calandra is an award-winning journalist and author of books he has written extensively on health and medicine. His work has appeared in national and regional magazines and newspapers.