Guillain-Barré syndrome in recipients of A/New Jersey influenza vaccine.

In late 1976, when 32% of the eligible population of Ohio received the A/New Jersey influenza (swine flu) vaccine, systematic contact of neurologists was used to evaluate the possible association of Guillain-Barré syndrome (GBS) with receipt of the vaccine. The overall rate of GBS was significantly higher among vaccine recipients (13.3/10(6)) than in nonrecipients (2.6/10(6)). Peak time of onset was two to three weeks after receiving the vaccine, and cases among vaccinees were less likely to have a history of antecedent infection than were cases in unvaccinated persons. Even when the effect of one highly associated vaccine lot was removed, an elevated risk of GBS remained in vaccinees regardless of manufacturer or vaccine type (bivalent or monovalent). Systematic surveillance is needed for rare serious reactions from all vaccines.