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Multiple sclerosis: Is there a risk of worsening after yellow fever vaccination?
Caroline Papeix1, Julie Mazoyer1, Elisabeth Maillart1
1Department of Neurology Pitié-Salpêtrière Hospital, APHP-6, Sorbonne University, Paris, France.
Background:
Yellow fever vaccine (YFV) is not advised for multiple sclerosis (MS) patients because of the potential risk of post-vaccine relapses.
Objective:
To assess the risk of relapsing-remitting multiple sclerosis (RR-MS) worsening after YFV.
Methods:
Non-interventional observational retrospective, exposed/non-exposed cohort study nested in the French national cohort including MS.
Results:
128 RR-MS were included. The 1-year annualized relapse rate (ARR) following YFV did not differ between exposed: 0.219 (0.420) and non-exposed subjects: 0.208 (0.521) (p = 0.92). Time to first relapse was not different between groups (adjusted hazard ratio (HR) = 1.33; 95% confidence interval (CI) = 0.53-3.30, p = 0.54).
Conclusion:
These results suggest that YFV does not worsen the course of RR-MS.
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