The world now has COVID-19 vaccines, of which more and more people are receiving their doses every day. A year and a half ago the world did not have COVID-19 vaccines, though it was fast becoming clear how soon it would need them. The subsequent development of the ones now being deployed around the world took not just less than a year and a half but less than a year, an impressive speed even to many of us who never dug deep into medical science. The achievement owes in part to the use of mRNA, a term most of us may recall only dimly from biology classes; through the pandemic, messenger ribonucleic acid, to use its full name, has proven if not the savior of humanity, then at least the very molecule we needed.
One shouldn’t get “the idea that these vaccines came out of nowhere.” On Twitter, Dan Rather — these days a more outspoken figure than ever — calls the prevalence such a notion “a failure of science communication with tragic results,” describing the vaccines as “the result of DECADES of basic research in MULTIPLE fields building on the BREADTH and DEPTH of human knowledge.”
You can get a clearer sense of what that research has involved through videos like the animated TED-Ed explainer above. “In the twentieth century, most vaccines took well over a decade to research, test, and produce,” says its narrator. “But the vaccines for COVID-19 cleared the threshold for use in less than eleven months.” The “secret”? mRNA.
A “naturally occurring molecule that encodes the instructions for occurring proteins,” mRNA can be used in vaccines to “safely introduce our body to a virus.” Researchers first “encode trillions of mRNA molecules with instructions for a specific viral protein.” Then they inject those molecules into a specially designed “nanoparticle” also containing lipids, sugars, and salts. When it reaches our cells, this nanoparticle triggers our immune response: the body produces “antibodies to fight that viral protein, that will then stick around to defend against future COVID-19 infections.” And all of this happens without the vaccine altering out DNA,
While mRNA vaccines will “have a big impact on how we fight COVID-19,” says the narrator of the Vox video above, “their real impact is just beginning.” Their development marked “a turning point for the pandemic,” but given their potential applications in the battles against a host of other, even deadlier diseases (e.g., HIV), “the pandemic might also be a turning point for vaccines.”
Based in Seoul, Colin Marshall writes and broadcasts on cities, language, and culture. His projects include the Substack newsletter Books on Cities, the book The Stateless City: a Walk through 21st-Century Los Angeles and the video series The City in Cinema. Follow him on Twitter at @colinmarshall or on Facebook.