Study: 3 Types of COVID-19 Vaccines Deemed Safe for Use in Patients With MS

Researchers recommend vaccination against COVID-19 for patients with multiple sclerosis (MS) after confirming that several types of vaccines are safe and produced no significant adverse events.

Three vaccine types that protect against COVID-19—inactivated virus vaccines (IVVs), adenovirus vector vaccines (AdVs), and messenger RNA (mRNA) vaccines—were found to be safe for patients with multiple sclerosis (MS) to receive, according to a recent study.

The cross-sectional study, published in MSJ­—Experimental, Translational and Clinical, represents the first report on the safety of vaccines fighting SARS-CoV-2 infection, the virus that causes COVID-19, in people with MS (pwMS) from Latin America. “Taken together, our findings support the recommendation to promote vaccination for pwMS during the SARS-CoV-2 pandemic,” they wrote.

Since the World Health Organization declared the COVID-19 outbreak to be a pandemic, over 21 million cases (18.8% of the global total) have been reported in the Latin American and Caribbean region. Managing MS during the pandemic has raised concerns among providers, patients, and caregivers regarding access to treatments, rehabilitation services, laboratory and resonance monitoring, and counseling.

Although vaccination is highly recommended for pwMS, whether COVID-19 vaccination produces specific adverse effects (AEs) among the MS population or immune mechanisms may be altered by COVID-19 vaccines remains to be seen.

The investigators conducted their analysis between February 1, 2021, and April 30, 2021, distributing a questionnaire to patients 18 years or older who were registered in an MS patient organization and had received at least 1 dose of any of the COVID-19 vaccines available in their country.

Overall, 393 patients from 10 Latin American countries completed the questionnaire. The mean (SD) age of the participants was 41.5 (11.8) years, 82.4% were female, and the mean MS disease duration was 8.4 (8.2) years. Among the patients, 346 (88%) reported use of a disease-modifying therapy, and 27 (6.9%) claimed to have temporarily stopped treatment to get a COVID-19 vaccine.

All the patients had at least 1 dose of a COVID-19 vaccine, and 31.3% reported receiving 2 doses. By vaccination type, IVVs were administered in 150 (38.2%) patients, AdVs were given to 192 (48.8%), and mRNA vaccines were administered to 51 (13.0%). The mean time from vaccination to survey completion was 22.2 (23.5) days after the first dose and 16.5 (19.2) days after a second dose. The most common reasons for only receiving 1 dose were insufficient time had passed since the first dose (57.3%), lack of appointments available for a second dose (8.1%), and second dose discouraged due to AEs from the first dose (n = 1; 0.3%).

None of the patients reported serious AEs after receiving either a first or second dose of a vaccine. The safety profile of all COVID-19 vaccines in the patient population was characterized by "short-term, transient, mild-to-moderate adverse events," the authors noted, and no participants required hospitalization. AEs of any kind presented in 35.6% of those who received their first dose and 23.6% of those who received a second dose.

The most common AEs reported were injection-site pain, headache, fever, flu-like symptoms, fatigue, and muscle or joint pain. For those who received an IVV, 22.0% experienced AEs compared with those who received an AdV (46.4%) or an mRNA vaccine (35.3%; P < .01).

Between administration of the first and second doses, 10 (2.5%) pwMS were infected by SARS-CoV-2, all of whom had mild disease or were asymptomatic. Additionally, 5 (1.3%) participants reported having an MS relapse, all of which happened after their first dose of an IVV. The mean (SD) time to relapse after vaccination was 14.8 (4.2) days.

The study had some limitations, such as a relatively short follow-up period, a small number of patients, the inclusion a significant portion of patients who only received 1 dose, and total relapses may have been underestimated.

“Future studies are needed to further evaluate the humoral and T-cell memory responses in pwMS in other COVID-19 vaccines beyond mRNA-based ones,” wrote the investigators.


Alonso R, Chertcoff A, Eizaguirre MB, et al. Evaluation of short-term safety of COVID-19 vaccines in patients with multiple sclerosis from Latin America. Mult Scler J Exp Transl Clin. Published oneline November 29, 2021. doi:10.1177/ 20552173211061543