MMR Vaccine and Covid-19: A Myth or a Low Risk-High Reward Preventive Measure?

Abstract

65% sequence identity and viral homologs are detected in numerous coronaviruses, concluding that the observed homology is similar to an anamnestic reaction to SARS-CoV-2 by mounting IgG/IgM response of rubella antigen and that MMR will not prevent COVID-19 infection but could potentially reduce poor outcome, which may be more of a speculation without appropriate randomized control trials [7]. In summary, while there are many theoretical hypotheses to prove the concept of trained immunity offered by BCG and MMR vaccines, well-designed controlled studies are needed, before considering MMR vaccination as a low risk-high reward tool to prevent COVID-19.

COVID-19 susceptibility and vaccination coverage for measles, rubella and mumps in students and healthcare workers in Trieste hospitals (NE Italy)

“…MMR vaccines could induce the formation of neutralizing antibodies that cross-react with other viruses, known as the overlapping of vaccine epitopes and amino acid residues between Sars-Cov-2, measles, and rubella glycoproteins. [4] There have been reports of patients infected with Sars-Cov-2 who developed neutralizing antibodies against measles. [5] In addition, a significant inverse correlation has been reported between mumps IgG titers due to MMR vaccine and COVID-19 severity, not age-related [6] , and between COVID-19 severity and MMR vaccination status (p = 0.013).…”

A case control study to assess effectiveness of measles containing vaccines in preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children

“…Two doses of measles containing vaccines are known to give a long-lastingimmunity, including in adulthood. [22][23][24] It will be interesting to check if MCVs received in childhood also offer protection against SARS-CoV-2 in the adult population and needs to be confirmed by further additional studies in the adult population.…”

Immunization During the COVID-19 Pandemic: Recommendations From Indian Academy of Pediatrics Advisory Committee on Vaccines and Immunization Practices

“…As of now, there is no evidence that BCG vaccine has a protective role against occurrence of SARS-CoV-2 infection [10]. Based on the current evidence, ACVIP does not recommend use of BCG or MMR vaccine for the protection of individuals against COVID-19 infection [10][11][12]. Various attributed potential nonspecific effects of the BCG vaccine in preventing COVID-19 as of now remain a hypothesis, because of multiple confounding factors [13].…”