Another is right around the corner, experts warn. And vaccines are quickly losing their effectiveness against Omicron.

(Originally published Jan. 7 in “What in the World“) Omicron is spreading so fast and making so many people ill that it’s depleting stocks of antivirals used to treat the most severe cases. The World Health Organization is reminding us that Omicron is still killing thousands of people a day, so please don’t dismiss it as a “mild” illness. The main reason most people who get Omicron aren’t dying or requiring hospitalization is that so many are now freshly vaccinated—and despite what some might like you to believe, that protection isn’t permanent. It fades within months.

It’s starting to dawn on the media that we can’t keep this up. We’re going to need a new vaccine. Fortunately, Pfizer/BioNTech, Moderna and Johnson & Johnson say they should have a vaccine tailored for Omicron ready within months. In the meantime, the debate is whether those who’ve had a booster shot should bother getting a fourth shot or just wait until that new vaccine rolls out. The answer seems clear: while a fourth shot might not do much good, it can’t do much harm either. So better safe than sorry. Until a better form of protection is available, the sensible thing to do is keep trying to boost one’s immunity using the original vaccine as antibodies ebb. There are blood tests that can measure just how high those are.

Worse, as the Times’ piece reminds us: “The speedy evolution of the virus occurs in large part because it has access to huge numbers of human hosts. If cases continue to accumulate at the current rate, or something close to it, the virus may continue to amass major changes — meaning the vaccines might need to be regularly updated.”

Indeed, experts warn that with the virus circulating so widely and spreading so rapidly, another strain may be just around the corner. The math of virology would suggest that the next strain will be at least as contagious, probably moreso, and less susceptible to current vaccines, but even less severe. But there’s no guarantees that we won’t see the brief emergence of a strain that is equally contagious and more severe.