“A universal SARS-CoV-2 vaccine is step one,” [Anthony] Fauci said. Step two would be a universal coronavirus vaccine, capable of protecting us not only from SARS-CoV-2 in all its forms, but also from the inevitable emergence of new and different coronaviruses that might cause future pandemics.
Vaccinating against all of them is a more elaborate challenge than taking on one or a few, but hypothetically possible. The broadest vaccine, though, isn’t likely to come from discovering a single, conserved region of the spike protein that all coronaviruses share, and that also reliably stimulates our immune system. This would be something like finding one spot that will blow up the entire Death Star—a little too easy. But we could find an array of frequently conserved regions that turn up in many coronaviruses.
“The real issue is better understanding the universe of coronaviruses,” says Wayne Koff, a biochemist and the head of the Human Vaccines Project. It’s theoretically possible to learn the major changes in the viral genome that make them most likely to spread widely and devastatingly in humans, so that our bodies can develop at least partial recognition of whichever dangerous new coronaviruses may come along: “What we’re especially concerned about are the coronaviruses that we don’t even know about yet.”