The new genetic vaccines to prevent Covid-19 infections use mRNA technology, instead of the approach used in traditional vaccines, like those for measles and polio. These new genetic vaccines appear to be safe and effective, as well as faster and cheaper to produce.
Pfizer and Moderna grabbed headlines, and ushered in hope, in announcing this month that each company has vaccines that preliminary data suggest to be 90-94% effective in preventing Covid-19 infections. This news is a much-needed salve to a world that has surpassed 1.37M deaths from Covid-19 since January 2020. These genetic vaccines are different from other vaccines, like those for the flu, measles, and polio, that we’ve benefited from for decades. Traditional vaccines, like that for measles, work by injecting a small amount of a weakened form of the virus into the body. Our white blood cells sense the virus and mount a defense against it by creating specific antibodies to fight it. Our immune system has cells, called T-lymphocytes, that remember that virus, so if our body encounters measles in the future, we can make the antibodies needed to fight it immediately. These traditional vaccines take years, or decades, to create, test, and be approved, and are expensive to produce. The Pfizer and Moderna vaccines take advantage of a different, genetic approach, that uses using a molecule called messenger RNA (mRNA), something you may not have thought about since high school biology class. In short, DNA is the genetic instruction manual for our bodies. mRNA makes a copy of that manual and carries it out of the cell’s nucleus to structures called ribosomes, where that manual is used to make proteins.
