Although there is trial data on the vaccine’s safety for the general population, there is not yet data specifically about risk for people with multiple sclerosis (MS).
However, evidence from other vaccines and advice from medical professionals can help to inform your choices.
Many people with MS have questions about the vaccine. Experts have answered several of those concerns directly, including whether the COVID-19 shot may cause inflammation or MS relapse.
Before making this decision, it is important to talk with your doctor about your current MS treatments and how getting (or opting out of) the COVID-19 vaccination may affect your health.
Here’s an overview of what medical researchers have to say.
Expert organizations such as the National Multiple Sclerosis Society (NMSS) say the mRNA vaccines, such as the Pfizer-BioNTech and the Moderna COVID-19 vaccines, are safe for people with MS.
They base this conclusion on two factors: the effects of these vaccines on the general populations in the testing stage and on the safety of past (non-COVID-19) vaccines for people with MS.
They note that the vaccination may require temporary changes to the schedule of MS treatments, but it is considered safe for most people.
In Canada, the National Advisory Council on Immunization (NACI) recommends a case-by-case risk assessment for offering COVID-19 vaccines to people with autoimmune conditions.
NACI cites the lack of evidence that an autoimmune disorder puts someone at risk for more severe COVID-19 disease as well as little to no data on the effect of vaccination on this population.
The Canadian Network of MS Clinics offered similar guidance for Pfizer-BioNTech and Moderna vaccines. The organization says there is no evidence of theoretical concerns about the safety of these vaccines for people with MS, and there is no convincing evidence previous (non-COVID-19) vaccines had adverse outcomes.
Two of the most commonly known vaccines, those made by Pfizer-BioNTech and Moderna, use mRNA technology. Others, such as the Oxford-AstraZeneca vaccine, use slightly different mechanisms.
In all cases, the vaccines work to teach the body to generate
Depending on your MS treatment, your doctor may recommend delaying or rescheduling a dose to make sure both your MS medicines and the vaccine work properly. The NMSS recommends continuing disease-modifying therapy (DMT) unless your doctor advises otherwise.
Some DMTs may lessen the effectiveness of the COVID-19 vaccine, but the vaccination will still offer some benefit. You may have to coordinate the timing of your vaccination with your therapy dose if you are currently using the following medications:
- ofatumumab (Kesimpta)
- alemtuzumab (Lemtrada)
- cladribine (Mavenclad)
- ocrelizumab (Ocrevus)
- rituximab (Rituxan)
NACI notes a concern that the mRNA vaccine would cause inflammation and therefore make some autoimmune conditions worse. That hypothetical concern was based on another application of mRNA technology. That application used mRNA to generate an immune response to fight cancer cells.
However, according to NACI, the COVID-19 vaccines do not work exactly the same way. These new vaccines have been developed to limit the inflammation risk.
A 2021 column in Practical Neurology discussed the concern that vaccines may cause transverse myelitis. The writers say that there were two cases of central nervous system (CNS) demyelination in the trial of the Oxford-AstraZeneca COVID-19 vaccine, which have not been peer-reviewed.
Only one of those was a case of vaccine-related transverse myelitis (TM). The authors write that vaccine-related TM has happened in other antiviral trials, and the evidence that links TM to vaccination is inconclusive.
The authors of the Practical Neurology report conclude there is no evidence that COVID-19 vaccines cause TM or trigger MS relapse.
The NMSS says the COVID-19 vaccine is unlikely to cause relapse or make MS symptoms worse. They go on to say the benefits of getting vaccinated outweigh the risks for people with MS.
COVID-19 vaccines are generally considered safe for people with MS. At this stage there is no specific data to show they are safe for people with autoimmune conditions, as people with these conditions were not specifically identified in clinical trials.
Consideration should be given to medications and treatments you may be taking and how they may affect the vaccine. MS treatment schedules may have to change in order to safely accommodate the COVID-19 vaccination.
Consultation with your doctor is important in order to make the best choice for you.