COVID-19 Vaccination Effects in Those with Multiple Sclerosis

August 1, 2023

A study published in Neurology Neuroimmunology & Neuroinflammation examined the safety of COVID-19 vaccines in people with multiple sclerosis (MS). The COVER-MS study funded by the National MS Society used an online self-reporting database called iConquerMS to gather information from 719 adults with MS and record information on vaccine side effects. In addition, they were also able to compare the effects of vaccines from different manufacturers and various MS therapies. 

Researchers found similar levels of vaccine side effects in people with MS as have been reported in the general population. After the first shot, 64% of participants reported some type of reaction within the first day (most commonly injection site pain, fatigue, and headache), and 17% reported a severe reaction. As with the general population, they found that women, White people, Latinx, younger people, and those who had already had a COVID-19 infection were at greater risk of vaccine reactions. The Oxford Astrazeneca vaccine was associated with more vaccine reactions than vaccines from other manufacturers.

Of the 442 participants who received a second vaccine dose, 74% experienced a reaction, and 22% reported a severe reaction. The effects of the second shot were similar to those of the first shot, and again younger people were at higher risk, though the Moderna vaccine was more likely (than the Pfizer vaccine) to cause a reaction in the second dose. 

Taking disease-modifying therapies for MS was associated with a lower risk of a vaccine reaction. In particular, those on S1PR modulators, alpha4-integrin blockers, and fumarates were seen to have fewer vaccine reactions. Those on B-cell-depleting therapies did not see this benefit, even when researchers accounted for the timing of the most recent dose.