There’s a lot to be learned about the omicron coronavirus variant, but scientists already know enough to prescribe a rational response to the threat. As the world waits for data, there’s plenty of useful knowledge that comes from evolutionary biology.
Revamping vaccine formulas and updating travel restrictions to slow down and catch omicron infections make sense, even understanding that the new variant might well fizzle out. Failing to prepare for a worst-case scenario would be a potentially disastrous mistake.
That worst case would require the coincidence of three simultaneous evolutionary advances. The variant would have to be transmissible enough to defeat the now-dominant delta strain and thereby spread throughout the human population. It would have to be virulent enough to overwhelm hospitals and provoke damaging lockdowns and restrictions. And it would have to be novel enough to infect and sicken the growing number of people who are immune to previous versions of SARS-CoV-2 by virtue of vaccines or previous illness.
That combination of evolutionary surprises is possible, but not all that likely.
Some researchers are scrambling to test how well omicron can stand up to the antibodies that are elicited by existing vaccines, and preliminary data show it can bypass these antibodies more readily than existing variants. But antibodies provide only part of the protection immune systems generate, so their potential vulnerability is only part of the story.