GBS may be a rare side-effect of
influenza vaccines, with an incidence of about one case per million vaccinations.
[10] Other estimates suggest the incidence of GBS among those receiving the vaccine was one case per 105,000 and that the GBS was not directly due to the vaccine but to a bacterial contamination of the vaccine that triggered GBS.
[11]
There were reports of GBS affecting some people who had received
swine flu immunizations in the
1976 U.S. outbreak of swine flu. Overall, there were about 500 cases of GBS—25 of which resulted in death from severe pulmonary complications— which, according to Dr. P. Haber, were probably caused by an immunopathological reaction to the 1976 swine flu vaccine. Other influenza vaccines have not been linked to GBS, though caution is advised for certain individuals, particularly those with a history of GBS