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COVID-19 Vaccine Reactions in People with MS Similar to General Population, Says New Society-Funded Study

November 17, 2021

Surveys of hundreds of people with MS enrolled in the iConquerMS network reveal that reactions to COVID-19 vaccine doses are similar to those experienced in the general population. People on certain disease-modifying therapies were less likely to experience reactions. This study adds to growing research on the safety of COVID-19 vaccination for people with MS.
  • People living with MS are seeking peace of mind on the safety and effectiveness of the COVID-19 vaccines. Research is underway to learn more about any specific medical impacts for people with MS receiving COVID-19 vaccinations. The National MS Society and the Accelerated Cures Project teamed up to gain insight into people’s personal experiences with the vaccines.
  • Between March and June 2021, participants in iConquerMS, an online people-powered research network initiated by the Accelerated Cure Project, answered surveys on reactions to COVID-19 vaccines, disease-modifying therapy use, and other factors. Most received the Pfizer-BioNTech vaccine (BNT162b2 ) or Moderna vaccine (mRNA-1273).
  • Among 719 people with MS who participated, 64% experienced a reaction after their first vaccine dose, and 17% had a severe reaction. Most common reactions were pain at injection site, fatigue, headache, and malaise (a general feeling of discomfort) – these are similar to those seen in the general population. People who were younger, female, had a previous COVID infection were more likely to have reactions.
  • Among 442 participants who reported receiving the second vaccine dose, 74% reported experiencing a reaction similar to those seen after the first dose, and 22% reported that they considered the reaction to be severe. People who were younger and had received the Moderna vaccine were more likely to have a reaction to the second dose.
  • People treated with alpha-4-integrin blockers (such as Tysabri) and sphingosine-1-phosphate receptor modulator (such as Gilenya or Mayzent) were less likely to have a severe reaction after the first shot. Those taking a sphingosine-1-phosphate receptor modulator or fumarate (such as Tecfidera or Vumerity) were less likely to have a reaction after the second shot.
  • The authors conclude that the results provide “a reassuring picture” for people with MS, and hope that the information addresses the concerns of those who remain hesitant to be vaccinated.
  • Research on the immune response to the vaccines in MS is underway.
Get COVID-19 Vaccine Guidance for People Living with MS
“COVID-19 Vaccination Reactogenicity in Persons With Multiple Sclerosis” by
Farren Basil Shaw Briggs, Farrah J. Mateen, Hollie Schmidt, Keisha M. Currie, Heather M. Siefers, Slavka Crouthamel, Bruce F. Bebo, Julie Fiol, Michael K. Racke, Kevin C. O’Connor, Laura G. Kolaczkowski, Phyllis Klein, Sara Loud, and Robert Nicholas McBurney, is available to read via open access in Neurology Neuroimmunology & Neuroinflammation (2022;9:e1104).

About Multiple Sclerosis

Multiple sclerosis is an unpredictable disease of the central nervous system. Currently there is no cure. Symptoms vary from person to person and may include disabling fatigue, mobility challenges, cognitive changes, and vision issues. An estimated 1 million people live with MS in the United States. Early diagnosis and treatment are critical to minimize disability. Significant progress is being made to achieve a world free of MS.


© 2022 The National Multiple Sclerosis Society is a tax exempt 501(c)3 nonprofit organization. Its Identification Number (EIN) is 13-5661935.