Some people who got the Johnson & Johnson/Janssen COVID-19 vaccine (the one-dose vaccine) have developed a condition known as Guillain-Barré syndrome. It’s happened often enough that the FDA has asked them to add a note about this to the patient fact sheet, but it’s still not considered to change the risk/benefit balance of getting your shot. (All the COVID vaccines are much safer than getting actual COVID.)
What is Guillain-Barré syndrome?
First, because it’s not obvious: The first word is pronounced “GEE-yawn” and the second rhymes with “hooray.” People sometimes just call it GBS.
GBS isn’t new: it’s already known to happen to about 1 in 100,000 people each year, and 60-80% of cases follow a bacterial or viral illness, like the flu or food poisoning, according to the GBS-CIDP Foundation International. GBS is also a known and rare side effect of the flu vaccine, although you’re more likely to get GBS from the actual flu than from the flu vaccine.
In GBS, the immune system attacks the insulation on our nerve cells. (If you think of the rubber coating around an electrical wire, each of our long skinny nerve cells is like that wire, and there are cells full of an insulating substance called myelin that surround it.) As a result, people may have weakness or numbness in the legs, or nerve problems in other areas of the body that could include trouble breathing or trouble moving the muscles of the face.
Guillain-Barré is usually not life threatening or permanent, but this can vary. According to the GBS-CIDP foundation, 90% of patients get through the acute phase of the illness within four weeks. During this phase, there are treatments that can limit the amount of nerve damage that occurs.
After the acute phase, it takes time to regain strength and nerve function, possibly months to years. Most people fully recover, but in some cases people may be left with weakness, pain, or fatigue that never completely goes away.
GBS may be a rare side effect of one COVID vaccine
The CDC and FDA noticed several cases of GBS turning up in VAERS, the database that lets anybody submit reports of possible adverse events from vaccines. This is the same database that anti-vaccine activists will mine for reports of deaths or other scary illnesses; the information in it is unverified. But when a concerning symptom shows up often enough, the CDC reaches out to investigate reports.
This is also how we found out about the blood clots that were serious enough to warrant a pause in administration of the J&J vaccine this spring. (Next time you see somebody suggesting that there are deaths or serious illnesses being ignored in VAERS, remember this. Reports of serious side effects that actually stand up to investigation are taken seriously.)
The FDA has added this information to the fact sheet given out with the J&J vaccine:
Guillain Barré syndrome (a neurological disorder in which the body’s immune system damages nerve cells, causing muscle weakness and sometimes paralysis) has occurred in some people who have received the Janssen COVID-19 Vaccine. In most of these people, symptoms began within 42 days following receipt of the Janssen COVID-19 Vaccine. The chance of having this occur is very low. You should seek medical attention right away if you develop any of the following symptoms after receiving the Janssen COVID-19 Vaccine:
* Weakness or tingling sensations, especially in the legs or arms, that’s worsening and spreading to other parts of the 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
Should this change my decision about getting the vaccine?
The risk of GBS after getting the J&J vaccine is still very small, and it’s only a tiny bit higher than the risk of GBS that you have just existing as a human being in this world. (Three to five times higher, but that means roughly three to five people per 100,000 instead of one per 100,000.)
The risks of the J&J vaccine, or of any COVID vaccine, are far less than the risks posed by an actual COVID infection. Nearly all COVID deaths in the United States are from people who have not been vaccinated, so if you are concerned about your health, getting the vaccine is still a better bet than not getting it.