COVID Vaccines and MS: Q&A

You’ve been asking our MS expert Dr. Adrian-Minh Schumacher your vaccine questions.

If you submitted a question we responded to you individually by email.

Here we’ve shared the questions and answers to help the Emilyn community!


I live in the UK and have had my first AstraZeneca Vaccine and am due to have the 2nd in June.

I’ve recently started taking Tecfidera after being diagnosed in February. Will Tecfidera make the vaccine useless?


First of all, having had the first dose of the vaccine is good news. It is definitely the right thing to do at the moment.

Regarding your MS medication: Tecfidera as a first-line therapy has a good ratio of efficacy versus suppression of the immune system. Compared to some other, high-efficacy drugs, it actually has a rather mild effect on the immune system. This implies that your lymphocyte counts are not highly reduced. I am sure your care team will check the lymphocyte counts every once in a while though too.

Given that they should be ok, there is absolutely no specific concern that the vaccination will have a strongly reduced efficacy or even be "useless".

Stay in contact with your care team, but in general the second vaccination in June sounds well timed and reasonable to me.


Should I have told my vaccination centre beforehand that I have MS?

Overall, there is no evidence that MS itself will affect the vaccination response. Treatment might be affected, depending on whether you are taking an MS drug and which one in specific.

In general, for a vaccinating team it is useful to know about the conditions you are suffering. However, it will most likely not influence the decision for you to get a vaccination.


I have just started on Ocrevus and have had blood clots in the past. Is it safe for me to get the COVID vaccine? I live in Australia.

Yes, it is safe for you to get a Covid-19 vaccine.

Ocrevus will not make it less safe, but might influence the immune response and therefore the efficacy of the vaccination. Therefore it is recommended to wait for about 12 weeks after the last Ocrevus infusion before you get vaccinated. The idea is to get the vaccine working better this way, giving you maximum protection from Covid-19.

However, if needed, it might be also ok and definitely safe to go earlier. Discuss this with your care team.

Regarding the blot clots: I assume you are referring to some of the vaccines that have shown very rare events of atypical venous thrombosis in vaccinated people.

As these were mostly younger people, it has been recommended by many European countries and also in Australia to use these vaccines (Oxford-AstraZeneca) more in elderly people (older than 50 years in Australia).

If you are younger than that, you should be able to get another vaccine that has shown no rare clotting events (e.g. Biontech/Pfizer or Moderna). It is so far not confirmed that blood clots in the past will influence the likelihood of this complication in somebody getting vaccinated with Oxford-AstraZeneca at all.


Is AstraZeneca or Pfizer is best for someone with MS? I am having an Ocrevus infusion every 6 months.

In general, there is no special difference regarding Covid-19 vaccines in MS that we are aware of.

Ocrevus works with all vaccines equally and will not make anything less safe, but might influence the immune response and therefore the efficacy of the vaccination. Therefore it is recommended to wait for about 12 weeks after the last Ocrevus infusion before you get vaccinated.

The idea is to get the vaccine working better this way, giving you maximum protection from Covid-19. However, if needed, it might be also ok and definitely safe to go earlier. You should discuss this with your care team.

Regarding the very rare side effects of AstraZeneca that are being discussed at the moment: Atypical venous thrombosis were mostly seen in younger people. It has been recommended by many European countries and also in Australia to use AstraZeneca above a certain age. Depending on where you live and how old you are, this might apply to you. There is no specific recommendation for MS though.


I've been recently diagnosed, I live in the US and haven't started any medications yet. Should I wait until after I start medication to get the vaccine?

The timing of a new treatment in relation to a COVID-19 vaccination really depends on the specific treatment.

In principle however, if you are still not entirely sure about the right treatment and you have the opportunity to get vaccinated now, it could be advantageous to get going with the vaccination now.

Often you have to do special pre-examinations which delay the commencement of an MS treatment.

Ideally you can use this time to already build up a robust protection against COVID before you start getting an immune treatment.

In general, most of the treatment that you could potentially start with do not even have a major effect on the immune response after vaccination.

You will of course have to discuss this with your care team as I cannot give you specific advice. I still hope this was helpful to you.


The CDC clearly states on their website that there is no safety data for the vaccine for people with autoimmune disorders yet we're being told to take the vaccine.

Can you comment on this and concerns such as ADE (antibody-dependent enhancements) and pathogen priming?

You bring up important points and interesting research items as well.

First, concerning safety, you are right about the CDC recommendations. They are based on the fact that there was only little specific data available on autoimmune patients and COVID-19 vaccinations. Still, the overall recommendation was made by other institutions and other countries, that people with autoimmune disease and immunosuppressed patients can also get the vaccine.

Key opinion leaders in the MS field strongly made the point that there is a higher benefit in getting vaccinated as soon as possible as an MS patient. Now, a few months after the approval of several vaccines, we at least have the first published datasets on over 500 patients with MS that received 1 or 2 doses of the Biontech/Pfizer vaccine, mostly coming from Israel.

In these studies, no specific effect on the relapse rate could be observed and the adverse events were also in line with the general side effects already known from the vaccine. Secondly, the rate of infection with SARS-CoV-2 in this vaccinated MS population was low, in fact none of the patients with 2 vaccinations got infected.
Still, we can only consider this rather preliminary data, because the observation period was rather short. On the other hand, this is actual clinical data from MS patients, which is very good and helps getting a general idea.

If you want to have a look yourself, the study is open access for everyone (you find the link here).

Regarding your second point, which is about antibody-dependent enhancement mechanisms and pathogen priming: These are special phenomenons that we know from other pathogens and that have to be characterized for every individual virus and vaccination.

They are still rather poorly understood, especially when it comes to the effects that happen in the human body (and not just in a cell culture dish). Currently we are not aware that autoimmunity enhances any of those mechanisms for the COVID-19 mRNA vaccines.

In general, the pre-binding confirmation of the spike protein coded for by the mRNA is supposed to lead to a decent amount of neutralizing antibodies and therefore limit the possibility of ADE. But we still don't understand these mechanisms not well enough to make a strong claim. This also is not my field of expertise.

We will have to wait for more research to happen. No matter what, key opinion leaders in the MS field, unequivocally state that MS patients should get vaccinated as everyone else. I strongly agree.

Still, I hope you found this helpful for your personal decision about getting vaccinated.

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COVID-19 Vaccine Guidance for People Living with MS (2021). COVID-19 Vaccine Guidance for People Living with MS. [online] National Multiple Sclerosis Society. Available at: https://www.nationalmssociety.org/coronavirus-covid-19-information/multiple-sclerosis-and-coronavirus/covid-19-vaccine-guidance.

Di Filippo, M. et al. mRNA COVID-19 vaccines do not increase the short-term risk of clinical relapses in multiple sclerosis. J. Neurol. Neurosurg. Psychiatry https://doi.org/10.1136/jnnp-2021-327200 (2021)

Achiron, A., Dolev, M., Menascu, S., Zohar, D.-N., Dreyer-Alster, S., Miron, S., Shirbint, E., Magalashvili, D., Flechter, S., Givon, U., Guber, D., Stern, Y., Polliack, M., Falb, R. and Gurevich, M. (2021). COVID-19 vaccination in patients with multiple sclerosis: What we have learnt by February 2021. Multiple Sclerosis Journal, 27(6), pp.864–870.

MS Coalition. Multiple Sclerosis Coalition | COVID-19 mRNA vaccine guidance for people living with MS. [online] Available at: https://ms-coalition.org/covid-19-mrna-vaccine-guidance-for-people-living-with-ms/.

‌CDC (2020). Coronavirus Disease 2019 (COVID-19). [online] Centers for Disease Control and Prevention. Available at: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/index.html.

This article provides general information and discussions about health and related subjects. The information and other content provided in this blog, website or in any linked materials are not intended and should not be considered or used as a substitute for medical advice, diagnosis or treatment.