Barts-MS rose-tinted-odometer: ★★★
Should I get an antibody test to prove that I have responded to the COVID-19 vaccine? No, you shouldn’t. Most diagnostic COVID-19/SARS-CoV-2 antibody tests are based on detecting antibodies to the so-called nucleocapsid protein and not the spike protein, which is the protein or immunogen used in the current vaccines. There are, however, a few private laboratories that are providing anti-spike protein antibody tests. However, antibody levels both from wild-type SARS-CoV-2 infection and the vaccine are not long-lasting and will wane with time. They also don’t tell us about T-cell responses. So even if you don’t seroconvert and are found to have no anti-spike protein antibodies post-vaccine you may still have immunity to the virus, which is likely to protect you from getting severe COVID-19.
At the moment we don’t know what to do with the seroconversion information, i.e. in patients who don’t seroconvert do we revaccinate them? At the moment vaccinologists are saying no. I am a firm proponent of only doing tests as part of routine clinical practice if you are going to act upon them. As I won’t act on the information that somebody has or has not seroconverted post-vaccination I don’t want to know the result.
Yes, this information also applies to pwMS on anti-CD20 therapies (rituximab, ocrelizumab, ofatumumab) or S1P modulators (fingolimod, siponimod, ozanimod, ponesimod). I suspect when we see the data in pwMS on these two classes of therapy, those who don’t seroconvert will still have effector T-cell responses to the spike protein. Clearly, if the data shows I am wrong we will have to adapt our vaccination practice(s). This will then be evidence-based. However, until then #GetVaccinatedASAP.
One can ask what have we learnt from the COVID-19 saga? As they say, hindsight is 20/20 or perfect vision. However, at the time the pandemic hit us I think we the MS community overreacted to the potential risks associated with SARS-CoV-2 and COVID-19 in relation to MS and DMTs and now we are overreacting to the vaccine readiness issue.
It is quite clear from the study below that COVID-19 seronegative care home residents make a reasonably good anti-spike antibody response from the vaccine. This is telling me that they have immunological memory and that the immune system responds robustly to the vaccine. I see no reason why this won’t happen to pwMS on DMTs. Not having an antibody response or losing an antibody response to the SARS-CoV-2 be it from wild-type infection and/or a vaccine doesn’t mean you have lost your immunity to the virus; in all likelihood, it will be there to protect you from getting severe COVID-19.
Blain et al. Spike Antibody Levels of Nursing Home Residents With or Without Prior COVID-19 3 Weeks After a Single BNT162b2 Vaccine Dose. JAMA. Published online April 15, 2021. doi:10.1001/jama.2021.6042
Disclaimer: Please note that the opinions expressed here are those of Professor Giovannoni and do not necessarily reflect the position of the Barts and The London School of Medicine and Dentistry nor Barts Health NHS Trust.