What to Know About the COVID Vax and Guillain-Barré Syndrome

This rare neurological disorder is being linked with one of the shots—should you be worried?

by Erin L. Boyle Health Writer

If it feels like you can’t look at the headlines lately without there being another story about the COVID vaccines, we feel you. This week? It’s all about the Janssen-made Johnson & Johnson (J & J) COVID-19 vaccine and Guillain-Barré Syndrome (GBS). If you saw that and thought a) Whoa…. and b) Whaa?? we feel you there, too.

Here are the details you need to know. On July 13, the U.S. Food and Drug Administration (FDA) announced revisions to its vaccine recipient and vaccination provider fact sheets for the J & J vaccine, to include a warning about an “observed increased risk” of GBS, a rare autoimmune disease, in a small amount of people after vaccination. This is not connected to the vaccine’s pause in distribution back in April. (That was over concerns of a rare blood-clotting disorder—and after reviewing the evidence, officials re-started distribution, with a caveat for women younger than 50 to be aware of the rare risk of blood clots).

In this new warning, FDA officials cited Vaccine Adverse Event Reporting (VAERS) data, showing 100 preliminary reports of GBS after approximately 12.5 million J & J doses were administered. Of those, 95 cases were serious, needing hospitalization, and one person died. Symptoms typically happened within 42 days after receiving the vaccine, according to the FDA. Officials at the Centers for Disease Control and Prevention (CDC) say that cases were mostly reported about two weeks after vaccination and largely in men, 50 years and older.

During the J & J vaccine trials, there were two cases of GBS—one was in the vaccine group, but the other was in the placebo group (which didn’t receive the vaccine). At the time, FDA officials said that these cases were “unlikely related” to the vaccine but that “a causal relationship cannot be definitively excluded.” Despite the new warning, the FDA official stance remains that although evidence suggests an association between the J & J vaccine and increased risk of GBS, there is “insufficient to establish a causal relationship.”

J & J company officials say the risk of developing Guillain-Barré is very low—but when you’re talking about a neurological disorder where the body’s immune system damages nerve cells, leading to muscle weakness and in severe cases, paralysis… well, people get nervous. So how worried should we really be?

What the Numbers Really Mean

It's important to put this news into perspective with numbers, to better interpret and understand risks, says Philip H. Smith, Ph.D., an epidemiologist, public health expert, and assistant professor in the department of kinesiology, nutrition, and health at Miami University in Oxford, OH. For instance: There’s less than a 1 in 100,000 chance of getting GBS from the J & J vax based on what we now know, he points out. And that’s putting aside any cases of GBS that might’ve happened for reasons other than the COVID shot (an increased risk of GBS has been seen in some people because of a flu shot or shingles vax, among other things).

Reality check #2: “When risks are unfamiliar, it can be helpful to relate the risks to something more familiar,” Smith says. Like take lightening, for example. “The National Weather Service estimates that our risk of being struck by lightning during our lifetime is about 1 in 15,000,” he says. “So, you are 5 or 10 times more likely to be struck by lightning during your lifetime, compared to your risk of developing GBS after getting the Johnson & Johnson vaccine, either because of the shot or coincidentally.”

Here’s another comparison: One in 600 people in the U.S. who were alive at the beginning of 2020 died from COVID-19. “To me, that is a much more frightening number than the risk of GBS from the Johnson & Johnson vaccine,” he says. “Unvaccinated people are at much greater risk of getting seriously ill or dying from COVID-19 than they are of getting GBS from the Johnson & Johnson vaccine.”

COVID and Guillain-Barré Syndrome

Here’s a newsflash: COVID itself has been linked to GBS, says Purvi Parikh, M.D., an allergist and immunologist at NYU Langone Health in New York City, spokesperson for the Allergy & Asthma Network, and co-investigator for the COVID-19 vaccine trials. GBS happens when the body’s immune system mistakenly damages its own healthy nerve cells, typically occurring in 3,000 to 6,000 in the U.S. (or roughly 10 per a million). Most people with it recover fully, but some have permanent nerve damage, according to the CDC.

It’s not contagious, or inherited, but one of its causes appear to be infection—hence the COVID connection. The numbers of GBS could possibly be much higher in those who had the coronavirus than the 100 reported after the J &J shot, Dr. Parikh says. Several large studies, including the Global Consortium to Study Neurological Dysfunction in COVID-19 and Neurocritical Care Society’s international data collection collaborative, could help determine exact numbers of COVID-related GBS cases, but all the results aren’t yet in.

So Is the J & J Vax Safe?

The path forward seems pretty straightforward, Dr. Parikh says. The J & J shot is 66.3% effective at preventing COVID when fully vaccinated, and the observed increased risk of GBS is rare. “We do not have a clear cause-and-effect relationship,” she says. “It is not common enough to panic, and benefits of the vaccine far outweigh the risks.”

Still, if you got the J & J shot and you’re beginning to freak a little, the FDA’s Fact Sheet for Recipients and Caregivers has info for you. It says that people who’ve had the J & J shot should get medical attention right away if they develop any of the following symptoms:

  • Weakness or tingling sensations, including in the arms and legs, especially if it isn’t getting better and is going to other areas of your body.

  • Difficulty walking.

  • Difficulty with facial movements, including speaking, chewing or swallowing.

  • Double vision or inability to move eyes.

  • Difficulty with bladder control or bowel function.

In the meantime, the CDC says that officials will “continue to monitor for and evaluate reports of GBS occurring after COVID-19 vaccination and will share more information as it becomes available.” In other words, rest easy: The pros are on it.

Erin L. Boyle
Meet Our Writer
Erin L. Boyle

Erin L. Boyle, the senior editor at HealthCentral from 2016-2018, is an award-winning freelance medical writer and editor with more than 15 years’ experience. She’s traveled the world for a decade to bring the latest in medical research to doctors. Health writing is also personal for her: she has several autoimmune diseases and migraines with aura, which she writes about for HealthCentral. Learn more about her at erinlynnboyle.com. Follow her on Twitter @ErinLBoyle.