Six people got blood clots after taking the Johnson & Johnson vaccine. Time to panic?

If you received the Johnson & Johnson vaccine for COVID-19, should you be worried?

The leaders of the Centers for Disease Control (CDC) and the FDA issued a statement this morning suggesting a pause in the administration of the J&J vaccine. As they wrote:

CDC and FDA are reviewing data involving six reported U.S. cases of a rare and severe type of blood clot in individuals after receiving the J&J vaccine. In these cases, a type of blood clot called cerebral venous sinus thrombosis (CVST) was seen in combination with low levels of blood platelets (thrombocytopenia). 

My wife had this vaccine. This is serious business.

But let’s examine what the risk is.

How do the risks of COVID-19 and the J&J vaccine compare?

Let’s do a little basic math.

According to the CDC, using the most recent weekly averages, here are the number of people likely to be getting positive tests for the first time, hospitalizations, and deaths from COVID over the next 12-week period.

  • Cases: 769,824
  • Hospitalizations: 64,032
  • Deaths: 8,532

What is the base? Well, there are 328 million people in the United States. Of those, 66 million have been vaccinated. And 31 million have been diagnosed with COVID. That leaves a base of 231 million. Of course, some of them got the disease without knowing it, and there are a very small number of people who get infected again after the disease once, but basically, there are 231 million people left to infect.

That means in a 12-week period, the proportion getting infected, hospitalized, and dying of COVID are as follows:

  • Getting COVID: 3,333 per million
  • Hospitalizations: 277 per million
  • Deaths: 37 per million

Those numbers would be higher if I extended them over more than 12 weeks, accounted for the rising number of cases, and included an estimate of the number of people who were already unknowingly infected and therefore most likely immune, but let’s call that a conservative estimate of the risk of COVID.

In comparison, what are the risks from the J&J vaccine? According to the CDC, health providers have administered 6.8 million does of the J&J vaccine, and they have recorded a total of six instances of the blood clotting reaction. No one has died, and with so few cases, you cannot be certain that the vaccine caused the reaction. But if it did, the measurable risk is 6 out of 6.8 million, or:

  • Blot clot incidence for J&J vaccine recipients: 0.9 per million.

Based on the information we have now, you have a one in a million chance of getting a blood clot after receiving the J&J vaccine, compared to a risk 41 times as great of dying from COVID and a risk 300 times as great of getting a serious enough case of COVID to be hospitalized, and potentially suffering from COVID aftereffects for years.

It was worth it — and it still is

The FDA rushed these vaccines into use, much faster than usual, but there were still clinical tests of tens of thousands of people performed first that showed a negligible number of serious side effects and a high degree of vaccine effectiveness.

The vaccines — all of them — are highly effective. The number of people who get infected, hospitalized, or die of COVID after getting a vaccine is minuscule. As Dr. Anthony Fauci said, “The several deaths reported so far among people already fully vaccinated were among elderly individuals who may have had underlying health conditions and may not have mounted a strong immune response when vaccinated . . . I don’t think there needs to be any concern about any shift or change in the efficacy of the vaccine.”

I’m happy that my wife got the J&J vaccine, and is protected from the serious risk of a deadly case of COVID-19. I am not worried about the one-in-a-million chance that she could get a blood clot, just as I don’t lie awake at night wondering if she’ll get hit by a car while crossing the street or accidentally stab herself while slicing vegetables in the kitchen.

I am pleased that the government is looking closely into these cases of side effects from the J&J vaccine, and pausing its administration in the meantime. But if they decide to resume vaccine shots with J&J, I’ll trust them, because this is a very small number of potentially serious reactions.

Please, if you are eligible, get vaccinated as soon as possible. If you don’t, I’m worried about your getting sick and about your possibly infecting others. I am at least 300 times more worried about that than whether you might have a serious side effect from getting the shot. If you’re thinking rationally, that’s how you ought to think about it.

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  1. Josh, my wife and mother in law both took the J & J. I have not gotten vaccinated. I’m not against vaccines just not sure if I should do it when when the recovery rate is better than 95% without getting vaccinated and I am not in the group of 65 & older where more than 80% of the deaths came from. I’m also not in the group that have any of the ailments found among more than the 90% that died ( wife & mother in law are).
    As far as safety is concerned, if u felt it was okay or even great to get vaccinated u should continue to feel that way. There’s risks with every medication, vaccine, or treatment in existence. The odds are in your favor that your fine.

  2. Thanks Josh, for this timely post. After hesitating because I tend to be cautious about what I add to my body, I received the J & J vaccine yesterday. Please note that one person has died in the US from a blood clot after receiving the J & J vaccine.

    From the Johns Hopkins daily Health Security Headlines for today:
    Johnson & Johnson Vaccinations Halt Across Country After Rare Clotting Cases Emerge (New York Times) Injections of Johnson & Johnson’s single-dose coronavirus vaccine came to a sudden halt in much of the country on Tuesday after federal health agencies called for a pause in the vaccine’s use following the emergence of a rare blood clotting disorder in six recipients. All six were women between the ages of 18 and 48 and all developed the illness within one to three weeks of vaccination. One woman died and a second woman in Nebraska has been hospitalized in critical condition.

  3. @Jim, your analysis seems rather flawed – at least in the way you articulate it.

    When it essentially costs you “nothing” (oh, you MAY feel sick for a couple days after your second jab), your investment vs a long tail risk with HUGE consequence (Death), should be a no-brainer. It’s a gimmie.

    If you are saying you’d rather wait to let others who may need it more go first – fine, but that is not clear from what you said.