Ask the Expert: Jorge Correale, M.D.

Is it OK for people with MS to be vaccinated?

Yes. Anyone with MS should receive standard vaccinations, including an annual flu shot, unless there is a specific reason not to, such as an active infection. For the American Academy of Neurology’s most recent immunization guideline, our panel of doctors reviewed all of the available clinical evidence and found that preventing infections through vaccines is an important part of medical care for people with MS. If you have MS, you should feel comfortable getting your recommended vaccinations.

What is the best timing for administering vaccines, considering that some people with MS may be taking medications that affect their immune response?

Your doctor will check your vaccination status as soon as possible after diagnosis and provide any necessary shots according to the Centers for Disease Control and Prevention’s annual recommendations. If you’re prescribed an immunosuppressive or immunomodulating medication, you should get vaccinations at least four to six weeks before you begin drug therapy; that will give your body enough time to respond to the vaccine.

You can also be vaccinated if you’re already being treated with these MS drugs, as long as the vaccines are not produced with live viruses. (A live vaccine contains a weakened version of a virus, as opposed to an inactivated one.) Because there’s a chance of systemic infection, live vaccines should not be given when a person’s immune system is strongly suppressed by drugs or disease. If you are experiencing an MS relapse, your doctor is likely to delay immunizations until the flare-up subsides.

Do vaccinations increase the risk of an MS relapse?

Generally, no. For most vaccines, there’s no increase in new MS exacerbations or other complications, except for the circumstances mentioned in the previous response. For some vaccines—such as those for human papillomavirus (HPV) or yellow fever—there have been some occasional reports, but no controlled studies, of MS patients having a greater risk of flares. In counseling you about your options, your doctor will explain the dangers of a certain disease versus the potential risks of vaccinating against it.

Are people with multiple sclerosis more likely to develop vaccine-preventable infections?

There’s no evidence that MS alone increases the risk of such infections. Instead, anyone who isn’t immunized against a particular preventable disease is at a higher risk of getting it, regardless of whether or not that person has MS. However, there is some evidence that infections may trigger MS relapses and accelerate disease progression.

Do MS medications reduce the effectiveness of vaccines?

Not enough clinical evidence is available for all MS drug treatments to say whether or not this is the case. In some studies aimed at answering this question for specific MS drugs, adequate protection has been observed after vaccination. But bear in mind that with some other MS drugs, the immunological response after vaccination is a bit lower. That’s why it’s important to discuss the benefits and risks of vaccination with your doctor.

Jorge Correale, M.D.
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Jorge Correale, M.D.

Jorge Correale, MD, is an author of the American Academy of Neurology’s 2019 Practice Guideline Update Summary: Vaccine-Preventable Infections and Immunization in Multiple Sclerosis.