MMR vaccine is critical, but not to help with COVID

Dear Dr. Roach: We have friends who got the measlesmumps-rubella vaccine believing it will help with exposure to COVID-19. What are your thoughts? — P.H.

Dear P.H.: The World Health Organization has reported an increase in measles deaths since 2016, and that trend has accelerated in the past year. The COVID-19 pandemic certainly is having an effect on measles vaccination, and with a drop in vaccination comes a loss of herd immunity, meaning that a measles epidemic could spread in the population. Mumps and rubella are important too, but measles is incredibly infectious, far more so that COVID-19. And it is fatal in perhaps 1 case in a thousand. At a global level, getting children immunized against measles remains critical.

A study published in November 2020 showed that people with high antibody titers to mumps had less severe COVID-19 symptoms than those who had low antibody titers. It’s possible that people with generally strong immune systems, as evidenced by high titers to mumps, will have better outcomes if infected by COVID-19, rather than it being a specific effect of mumps antibodies. The authors of the paper do not currently recommend booster shots for MMR.

At the time of this writing, several COVID-19 vaccines have been shown effective and at least two have been approved by the Food and Drug Administration in the U.S.. I suspect that they will be in the process of being given to the highest risk groups on the day you are reading this. They are much more likely to provide protection than an MMR booster, in my opinion.