No Rise in GBS With 2009 H1N1 Vaccination

Worries about a rise in Guillain-Barre syndrome during the 2009 H1N1 vaccination campaign were unfounded. Only 35 cases of the acute autoimmune neuropathy were reported to the CDC or the FDA's voluntary reporting system, VAERS, at the end of last year, say researchers at the ongoing annual meeting of the American Academy of Neurology in Toronto.

The 2009 H1N1 (or swine flu) vaccination campaign began in earnest in mid-October of last year, and approximately 100 million vaccinations were administered in the United States. Consequently the rate of GBS associated with vaccination was 3.5 per 10 million. All but 1 case occurred within 6 months of vaccination; 23 cases occurred within 2 weeks of inoculation. The annual background rate of GBS is about 1-4 cases per 100,000. (The 2009 H1N1 vaccine protects against GBS, anyone?)

Original worries about a vaccine-associated increase in GBS stemmed from the observed rise in the condition during the 1976 swine-flu vaccination program.

VAERS = Vaccine Adverse Event Reporting System.