OBJECTIVE: To examine the risk of MS in people vaccinated against pandemic influenza A (H1N1) with Pandemrix (GlaxoSmithKline, Middlesex, UK) compared with unvaccinated people over 8-10 months.
SETTING: 1 024 019 were vaccinated against H1N1 and 921 005 remained unvaccinated.
RESULTS: Risks for multiple sclerosis remained unchanged.
CONCLUSIONS: Results for the safety of Pandemrix over 8-10 months of follow-up were reassuring -notably, there was no change in the risk for Guillain-Barré syndrome, multiple sclerosis, type 1 diabetes, or rheumatoid arthritis. Relative risks were significantly increased for Bell’s palsy, paraesthesia, and inflammatory bowel disease after vaccination, predominantly in the early phase of the vaccination campaign.