Occurrences of the Guillain–Barré Syndrome (GBS) After Vaccinations with the 1976 Swine A/H1N1 Vaccine, and Evolution of the Concern for an Influenza Vaccine-GBS Association

Abstract

Implementation of a public vaccination program with A/New Jersey (A/NJ) vaccines in 1976 led to the recognition of an increased risk among vaccinated persons of developing the neurological disorder known as Guillain–Barre Syndrome (GBS). The attributable risk was 8.8 among adults in the 6-week period after vaccination or about 1 case per 100,000 vaccinations. Skepticism of the statistically significant association was resolved with a subsequent careful assessment in two states in the USA that confirmed the association. Subsequent efforts to confirm an association between other influenza vaccines and occurrence of GBS have mostly failed to identify an association but a suggestion of about one case of GBS per one million vaccinations has been reported. GBS has been associated with various other infections, illnesses, vaccinations, and other disorders. Campylobacter jejuni infections are accepted as inducing a risk for GBS and evidence suggests antiganglioside immune responses that react with the nerve myelin sheath as the mechanism. To assess this possibility, A/NJ and some other influenza vaccines were all shown to induce antiganglioside antibodies in mice; however, a relation of this finding in mice to GBS in humans has not been provided.