WASHINGTON (AP) – The US on Tuesday recommended a “break” from the use of the Johnson & Johnson single-dose COVID-19 vaccine to investigate reports of rare but potentially dangerous blood clots, a development that will overcome the introduction of vaccines. could endanger the whole world.
The Centers for Disease Control and Prevention and the Food and Drug Administration announced that they were investigating unusual clots that appeared 6 to 13 days after vaccination. The FDA commissioner said she expected the break to last a few days.
The clots occurred in veins that drain blood from the brain and occurred along with low platelets, the fragments in the blood that normally form clots. All six cases involved women between the ages of 18 and 48. One person died, and all cases are still under investigation.
In the US, more than 6.8 million doses of the J&J vaccine have been given, the vast majority with no or mild side effects.
Any delay in the spreading of the shots could have widespread repercussions for the global vaccination effort. The J&J vaccine was particularly promising for less affluent countries, as its single-dose regimen and relatively simple storage requirements would make it easier to use in the developing world.
The FDA said the cases investigated resemble unusual clots that European authorities say may be related to another COVID-19 vaccine not yet approved in the US, from AstraZeneca. European regulators have emphasized that AstraZeneca risk appears to be lower than the possibility of having blood clots from birth control pills.
Federally run mass vaccination sites will pause use of the J&J shot, and states and other providers are expected to follow suit. The other two authorized vaccines, from Moderna and Pfizer, make up the vast majority of COVID-19 injections administered in the US and are unaffected by the pause.
“I want to emphasize that these events seem extremely rare. However, the safety of the COVID-19 vaccine is a top priority, ”acting FDA Commissioner Janet Woodcock said at a news conference.
A CDC committee will meet on Wednesday to discuss the cases, and the FDA has also launched an investigation into the cause of the clots and the low platelet count.
Authorities have not seen similar clots after using the Pfizer or Moderna vaccines, said Dr. Anne Schuchat of the CDC.
FDA officials insisted Tuesday’s action was not mandated. Doctors and patients can still use J & J’s vaccine if they decide that the benefits outweigh the risks for individual cases, said Dr. Peter Marks.
The agencies recommend that people who have received the J&J vaccine contact their doctor if they experience a severe headache, abdominal pain, leg pain, or shortness of breath within three weeks.
J&J said in a statement that it was aware of the reports of blood clots, but no link to the vaccine had been established. The company also said it would delay the introduction of its vaccine in Europe as a precaution.
US health authorities warned doctors against using a typical clot treatment, the blood-thinning heparin. “In this setting, administration of heparin can be dangerous and alternative treatments must be given,” said the FDA and CDC.
European authorities investigating the AstraZeneca cases have concluded that clots resemble a very rare abnormal immune response that sometimes affects people treated with heparin, leading to a transient clotting disorder.
While it’s not yet clear whether the reports among J&J recipients are related, doctors would treat these types of unusual clots the way they treat people who have the heparin reaction – with different types of blood thinners and sometimes an infusion of antibodies, said Dr. Geoffrey Barnes. , a clot expert at the University of Michigan.
While authorities are investigating whether the clots are really related to the J&J vaccine, Barnes stressed that Americans should be vaccinated as soon as possible with the other two available vaccines, from Pfizer and Moderna.
“If you get the chance to get vaccinated with it, we strongly encourage that. The risks from COVID are real and they are high, ”said Barnes.
Jeff Zients, the White House’s COVID-19 response coordinator, said 28 million doses of the Pfizer and Moderna vaccines will be available to states this week, more than enough to keep up with the national rate of 3 million shots a day. despite the J&J pause.
When asked if the government overreacted to six of the more than six million vaccinations, Schuchat said the recommendations will come soon.
Because these unusual clots require special handling, “it was of the utmost importance for us to make it known,” she said. That said, the pandemic is quite severe and the number of cases is increasing in many places and the vaccination is critical.
States and cities quickly moved to introduce the hiatus. Dr. Howard Zucker, New York State Health Commissioner, said people who made appointments on Tuesday for J&J vaccines at state-run mass vaccination clinics will instead receive the Pfizer vaccine.
The City of Dallas planned to initiate a home vaccination program with the J&J vaccine for homebound people or the elderly. The city said it will pause the program until more guidance is released.
The J&J vaccine received much fanfare for emergency use from the FDA in late February. Still, absorption makes up only a small fraction of the doses administered in the US. J&J is plagued by production delays and manufacturing defects at a contractor’s Baltimore factory.
Last week, the drug company took over the plant to scale up production in hopes of delivering on its promise to the US government to deliver about 100 million doses by the end of May.
According to data from the CDC, only about 9 million of the company’s doses have been delivered to the states and are awaiting delivery.
So far, concerns about the unusual blood clots have centered on AstraZeneca’s vaccine, which has not yet received approval in the US. Last week, European regulators said they have found a possible link between the injections and a very rare type of blood clot that occurs together. with low platelets, one that seems to be more common in younger people.
The European Medicines Agency stressed that the benefits of the vaccine outweigh the risks for most people. But several countries have imposed restrictions on who can receive the vaccine; Britain recommended offering alternatives to people under 30.
But the J&J and AstraZeneca vaccines are made with the same technology. Industry-leading COVID-19 vaccines train the body to recognize the spike protein that coats the outer surface of the coronavirus. But the J&J and AstraZeneca vaccines use a cold virus called an adenovirus to deliver the spike gene into the body. J&J uses a human adenovirus to make its vaccine, while AstraZeneca uses a chimpanzee version.
US stock markets initially fell on the J&J news, but some indices rose slightly late in the morning. Shares of Johnson & Johnson fell nearly 3 percent, an unusually large drop for the drug giant, with more shares switching hands in the first two hours than on an average day.
Associated Press authors Emily Wagster Pettus, Karen Matthews, Jill Bleed and Linda A. Johnson contributed to this report.