There’s A New Flu Vaccine Every Year. Why Can’t A Coronavirus Vaccine Be Ready That Fast?
To answer this, it’s important to understand why we don’t just use the same flu vaccine each fall. “Influenza viruses change over time, they drift,” explains Dr. Pedro Piedra, professor in molecular biology and microbiology at Baylor College of Medicine, in Houston, Texas. This drift comes from very tiny genetic alterations that occur frequently in a key part of the virus. These are essentially cosmetic changes, not structural ones: the virus reproduces the same way, and makes us sick in the same way. It’s still an influenza virus, just with different surface decorations. But it’s those decorations that trigger the body’s immune response.