A Pause on the J&J COVID Vaccine

There has been some news about one of the COVID vaccines today, and I wanted to put it into context for you. Based on advice from the CDC and the FDA, the US has paused the distribution of the Johnson and Johnson vaccine after six people developed a rare condition within three weeks of the shot, and one of them has died.

Cerebral venous sinus thrombosis (CVST) is a blood clot that forms in the large veins that drain blood from the brain. It's important to realize that CVST is a different condition from the much more common type of blood clots that may form in the legs, and can be related to smoking, birth control pills or COVID itself. Keep that in mind when reading articles about this.

My initial impression was that this was an overreaction - this is six out of nearly 7 million vaccine recipients, less than one in a million. If you look at how common CVST is in general, estimates are 2-5 cases per million per year, although more recent studies suggests that it could be even higher than that. So that means that in any random group of 7 million people who weren’t vaccinated, you might expect at least 14-35 cases of this condition. And withholding the vaccine, especially if there weren't others to fill the need, means less people vaccinated. Which of course means more infections and more variants. It also means more COVID deaths, since that’s what the vaccines are really proven to prevent. Many more people could die for lack of a vaccine than would have gotten this rare blood clot, even if it was related to the vaccine (which hasn’t even been proven yet).

But then I realized something. The CDC and the FDA made the right call here.

Am I worried that concerns about side effects feed vaccine hesitancy? Sure. But you know what could make it even worse? People getting the idea that potential side effects aren’t being take seriously. That to promote vaccination, we are just dismissing complications as necessary losses. And that’s a LOT more likely to promote vaccine hesitancy and conspiracy theories. It's better to actually stop to look at the data and draw conclusions in the open. The tough question isn’t whether the risk of dying of COVID is greater than the risk of dying of a vaccine side effect (it is by far, and here's a terrific graphic that explains that point). We need to know the risk of the Johnson and Johnson vaccine compared to other similarly effective vaccines that can be made available in a timely fashion. And we need to know how to recognize, diagnose and manage those risks. So there are a lot of variables here.

Look, no vaccine, medication or surgery is completely safe. Penicillin, which we give out like candy, has a rate of fatal allergic reactions of 20 per million. Car accident deaths in the US are 120 per million. And these 1 in a million cases of CVST may turn out to have not been directly caused by the vaccine. But to quote Dr. Ashish Jha, the dean of the Brown University School of Public Health and one of my favorite people to follow on this topic: “… confidence is built on having a system that takes adverse events seriously, investigates them and makes data-driven decisions.”

We need to continue to build confidence. It's easy to look at this phenomenal scientific and public health achievement and throw stones, but the process to ensure safety is well thought out and done in good faith. Even early in the rollout, there was some concern about a potential for blood clots, but these are so rare that there is no way that you would be able to pick up a side effect in testing that has an incidence of less than one in a million. If your criteria for launch is 100% safety, you would hardly ever have a drug, device or procedure available to treat anything. And the more we learn about this extremely rare possible side effect, the better prepared we will be to diagnose and treat it quickly if it does occur. That's also a benefit of the pause, since there are reasons not to use standard clot treatment in this case.

One more thing to keep in mind is that this pause - hopefully for a short time but long enough to carefully examine the evidence - will probably not affect the overall distribution plan in the US. J & J accounts for less than 5% of administered vaccines in this country. Unfortunately, a longer pause has the potential to impact underserved communities like homebound patients or thinly populated rural areas. This is a great option for these patients, since follow up vaccine logistics and high-tech refrigeration isn't needed, so hopefully we will have it available again soon. The CDC's advisory committee will have an emergency meeting tomorrow to determine if and when the vaccine distribution can resume, and if there are certain groups at high risk that should get a different shot.

It’s a hard decision either way. But I think that the FDA and the CDC made the right one.