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The idea that old vaccines might have a role in the fight against COVID-19 has been floated since the early days of the pandemic. Vaccines stimulate the broad, innate immune response, which appears to play a key role in fighting COVID-19. Can the approach bridge the time until entire populations are vaccinated specifically against SARS-CoV-2?
Three vaccines dominate the discussion: bacillus Calmette-Guérin (BCG) against tuberculosis; measles, mumps, and rubella (MMR); and oral polio vaccine (OPV).
To continue reading, go to MedPage Today, where this article first appeared.