Why the Johnson & Johnson COVID vaccine is paused

As the nation and the world move to vaccinate as many people as possible against COVID-19, the CDC and FDA announced Tuesday morning that the Johnson & Johnson vaccine distribution be paused to investigate a rare type of blood clotting.

In a joint statement, the FDA and CDC said that the pause of the single-dose vaccine is "out of an abundance of caution" while the agencies investigate reports of blood clots in women between 18 and 48.

"Right now, these adverse events appear to be extremely rare," the statement said. "Treatment of this specific type of blood clot is different from the treatment that might typically be administered."

Because of its single dose, the Johnson & Johnson vaccine has been seen as a faster way to end the COVID-19 pandemic. The other two vaccines, Pfizer and Moderna, are both two doses.

How long will the Johnson & Johnson pause last?

The pause isn't expected to last very long. During a media call between the CDC and FDA on Tuesday morning, FDA Acting Commissioner Janet Woodcock said it shouldn't be longer than a few days.

"I'd like to stress these events appear to be extremely rare. However COVID-19 vaccine safety is a top priority," "We expect it to be a matter of days for this pause."

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The challenge with the blood clots is that it also comes with reduced platelet counts, making the usual treatment for blood clots, the blood thinner heparin, potentially "dangerous." 

How rare are the blood clots?

A total of 6 women have reported to have blood clots in the week after getting the J&J vaccine. 

According to a statement from the FDA, the 6 women are all under the age of 50. 

To date, over 6.8 million Johnson & Johnson doses have been administered in the United States.

Dr. Matthew Sims, the director of infectious disease research at Beaumont, said on FOX 2 that this is a 'one in a million event' and we don't know if it's directly related to the vaccine.

"We don’t know what risk factors they had going into it. There’s a lot more we don’t know than we do know," said Dr. Sims. "I would be cautious on jumping the gun and worrying that I’m definitely going to get it because I got the shot."

He also cautioned against panic, saying that side effects are common.

"Most medicines on the market have some side effects in that range. If you ever read the brochure, you probably would be just as scared," he said.

What are the Johnson & Johnson side effects?

Both the FDA and CDC are recommending that people who received the vaccine who experience severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after receiving the shot should contact their doctor.

According to Sims, while the blood clots are rare, if you experience any of the symptoms that could indicate you may have one, you should contact your doctor. These symptoms are stroke-like and may include headaches that are severe and don’t go away, blurred vision, and seizures.

Johnson & Johnson said it is working closely with experts and regulators and said that "the safety and well-being of the people who use our products is our number one priority."

"We are aware of an extremely rare disorder involving people with blood clots in combination with low platelets in a small number of individuals who have received our COVID-19 vaccine," the company said in a statement. 

The company has also been reviewing these cases with European health authorities and has proactively delayed the rollout of the shot in Europe.

Does the Johnson & Johnson pause affect other vaccines?

The other two authorized vaccines, from Moderna and Pfizer, are not affected by the pause. Most health departments are rescheduled planned Johnson & Johnson vaccines with Pfizer or Moderna.

The J&J vaccine received emergency use authorization from the FDA in late February with great fanfare, with hopes that its single-dose and relatively simple storage requirements would speed vaccinations across the country. Yet the shot only makes up a small fraction of the doses administered in the U.S. as J&J has been plagued by production delays and manufacturing errors at the Baltimore plant of a contractor