Rare cases of an autoimmune disorder known as Guillain–Barré syndrome appear to be linked to the Johnson & Johnson COVID-19 vaccine, according to updated warnings issued this week by the FDA. However, the overall risk with the one-dose vaccine are small, and health officials indicate it should not discourage people from getting the shot.
The FDA updated label warnings this week for the COVID-19 vaccine manufactured by Janssen, a subsidiary of Johnson & Johnson. An updated fact sheet will be provided for doctors and patients, indicating there may be a potential increased risk of Guillain–Barré syndrome, but that health experts have not established a causal relationship, meaning they cannot be sure the vaccine actually causes the condition.
Guillain–Barré syndrome is a neurological autoimmune disorder that causes damage to the body’s nerve cells. This can cause muscle weakness, paralysis, and in rare cases, death.
According to the warning, the vaccine is associated with a three to five-fold increased risk of the disorder, and symptoms of the syndrome occur during a 42-day period after receiving the vaccine. Most of the cases have been reported about two weeks after getting the shot and appears most prevalent in men over the age of 50.
The new label warning states:
Reports of adverse events following use of the Janssen COVID-19 Vaccine under emergency use authorization suggest an increased risk of Guillain–Barré syndrome during the 42 days following vaccination.
Officials with the U.S. Centers for Disease Control and Prevention (CDC) say about 100 cases related to the vaccine have been reported, with 95 of those cases requiring hospitalization. There was one death reported. However, most people fully recover from the disorder, and the number of cases represents a miniscule fraction of the 12 million doses of the vaccine administered in the U.S. to date.
No signs of Guillain–Barré syndrome risks have been found with either the Pfizer or Moderna vaccines, whose 321 million doses to date account for most of the COVID-19 vaccinations given in the U.S.
The disorder is often linked to vaccines, but the exact cause is unknown. Earlier this year, the FDA placed a similar warning on the Shingrix vaccine, which is given to prevent shingles.
The warning comes amid a resurgence of cases of COVID-19 nationwide, following months of declining infection rates and deaths due to the wide distribution of the three approved vaccines. Those increasing rates appear to be occurring almost entirely among the unvaccinated, and is being driven by the spread of the Delta variant of the virus, which is believed to have its origins in India, which is being hit hard by the pandemic.
Since last year, when the outbreak was first detected, the U.S. has seen 33.8 million cases of COVID-19 and more than 606,000 deaths.
The potential link between the Janssen vaccine and Guillain–Barré syndrome is expected to be discussed at an upcoming meeting of the CDC’s Advisory Committee on Immunization Practices.