Only Janssen COVID-19 Vaccine Associated With Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is a rare, autoimmune disorder of the peripheral nervous system. Often triggered by a viral illness, GBS can cause severe muscle weakness and paralysis, and even mortality in 5% of patients.

There is a history, albeit rare, of association between vaccines and subsequent GBS. With this knowledge, COVID-19 vaccine investigators ensured special monitoring for GBS alongside other potential adverse events.

A JAMA study sought to determine if COVID-19 vaccination increased the risk of GBS. The investigators analyzed whether the Ad26.COV2.S (Janssen), BNT162b2 (Pfizer-BioNTech), or mRNA-1273 (Moderna) COVID-19 vaccines were associated with GBS within 21 or 42 days after vaccination.

There are 3000-6000 cases of GBS diagnosed each year in the US. Initial symptoms typically include weakness that starts in the legs and spreads to the arms. Decreased or debilitated reflexes are another common symptom. Due to affected cranial nerves, more than half of GBS patients experience facial weakness, difficulty swallowing, and eye muscle weakness or paralysis.

The investigators utilized the Vaccine Adverse Events Reporting System (VAERS) to determine verified instances of GBS following COVID-19 vaccination. The study comprised of 487651785 COVID-19 vaccine doses, administered to Americans 18 years and older. Of these, 3.7% (n = 17944515) were Janssen, 54.7% (n = 266859784) were Pfizer-BioNTech, and 41.6% (n = 202847486) were Moderna.

There were a total of 295 verified reports of GBS after COVID-19 vaccination. Of these individuals, 4.1% were Asian, 5.8% were Hispanic, 6.1% were Black, and 65.4% were White. The average person with GBS after COVID-19 vaccination was male (57.3%) and 59 years old.

Of the GBS cases, 93.2% (n = 275) required hospitalization. Additionally, 209 cases occurred within 21 days of vaccination, and 253 occurred within 42 days. GBS was most likely to occur after Janssen vaccination, in both the 21 days after vaccination and 42 days after vaccination periods.

The disproportionate reporting and imbalance after Janssen vaccination led the investigators to conclude the Janssen (Ad26.COV2.S) COVID-19 vaccine was associated with an increased risk of Guillain-Barré syndrome. Notably, there was no association between mRNA COVID-19 vaccination and subsequent GBS.