Viral infection, injury, and pregnancy are the most
frequently proposed triggers for
multiple sclerosis (MS). But there is no
scientific proof that they trigger MS in a person who does not already have the
In someone who already has MS,
a viral infection such as the flu can trigger a
relapse. There is no proof that flu vaccination (or
any other vaccination) increases the chance of a relapse. In fact, people with
MS may want to consider getting an annual flu shot to avoid infection and any
attacks it may trigger. But there is no evidence that the nasal
spray vaccine is safe for people with MS. If you have MS, talk with your doctor about whether a nasal spray vaccine is right for
Bennett KA (2005). Pregnancy and multiple sclerosis.
Clinical Obstetrics and Gynecology, 48(1):
How this information was developed to help you make better health decisions.