For the first time in the U.S. vaccine deployment, regulators pumped the breaks on an authorized coronavirus shot.
The Centers for Disease Control & Prevention and the Food and Drug Administration on Tuesday jointly recommended a temporary halt in the distribution of the Johnson & Johnson vaccine while regulators investigate six reports of unusual blood clots.
In all six cases, women between the ages of 18 and 48 were involved who developed central venous sinus thrombosis, an extremely rare form of blood clot in the brain. One of the women is dead and another in a critical condition.
Experts are not sure why these cases of blood clots have developed – or even if there is a clear cause-and-effect connection with the vaccine. However, there is no reason to suspect that rare blood clots are associated with other authorized vaccines from the USA.
“Instead of taking away confidence from other vaccines, it should actually inspire more confidence in the supervision of these vaccines, and it should certainly not deter the individuals who have been linked to doing Pfizer and Modern vaccines,” he said. the dr. Baltimore Internal Medicine Vivek Cherian told Insider.
About 68 million Americans have been completely vaccinated with Pfizer or Moderna’s disc since December, and a total of nearly 185 million doses have been administered. At that time, U.S. regulators did not detect any significant safety issues among people who received the vaccines. (The CDC monitors vaccine side effects through a tool called V-safe, and healthcare providers must report adverse reactions via an online system called VAERS.)
“There are a lot of careful investigations into these vaccines,” Peter Gulick, an associate professor of medicine at Michigan State University, told Insider.
He added that the recordings of Pfizer and Moderna “J&J” are months ahead in their production and rollout, and that regulators do not yet see any red flags. Even his HIV patients, Gulick said, did not report serious reactions.
JOIN US ON THURSDAY FOR A LIVING EVENT: Experts answer your questions about coronavirus vaccines and the risk of rare, severe blood clots.
In contrast, J & J’s vaccine was launched more recently: it was approved in late February and has so far been administered to just under 7 million Americans.
“When you start vaccinating people, you have a much, much, much larger sample size – in the millions,” Cherian said. In contrast, J & J’s clinical trial had just under 44,000 people. “So if you have these extraordinarily rare complications, sometimes you only see them before you really start.”
Pfizer and Moderna’s shots pose ‘virtually no risk’ of clotting
Nurse Janelle Roper, left, gives the Pfizer COVID-19 vaccine to fellow nurse Kate-Alden Hartman.
John McDonnell / The Washington Post via Getty Images
In an average year, only two to five out of every 1 million Americans develop central venous sinus thrombosis (CVST).
J & J’s vaccine has not yet exceeded normal background levels, with less than one CVST case for every 1 million doses reported so far. But researchers have also seen a number of CVST cases among people who received the coronavirus vaccine for AstraZeneca, which has many similarities with J&J.
At the beginning of April, European medical officials identified 169 CVST cases from more than 34 million people in the EU who got AstraZeneca’s chance. That is still only five cases per 1 million shots, but that was enough for European regulators to conduct an investigation. The UK now recommends that people under the age of 30 look for other shots, if available.
Both AstraZeneca’s and J & J’s are viral vaccines that introduce a coronavirus gene into the body using a genetically engineered
cold
virus. Some scientists wonder if the platform itself can be linked to solidification.
In contrast, Pfizer and Moderna’s vaccines are dependent on mRNA technology, which uses an extract from the coronavirus genome to elicit an immune response.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said during a webinar from the American Medical Association on Tuesday that the U.S. has identified only three CVST cases among the 68 million people who received the double dose of mRNA vaccines. .
In A Tuesday statement, Moderna also said he did his own comprehensive analysis and found no link between the shot and CVST or other forms of coagulation.
‘It is safe to say that there is virtually no risk in mRNA-based individuals [vaccines]”But we do not really have that information regarding the virus vector,” Cherian said.
But he added that even with the viral vector vaccines, “many, many less than even 1% of individuals actually have these side effects.”
By comparison, a November study found that 20% of COVID-19 patients admitted to the hospital developed blood clots in their veins.