Skip to content
Faye Flam

New Covid Variants Complicate the Question of Vaccine Mandates

Officials mulling new pandemic policies need to know how quickly vaccine protection wanes. But scientists don't have a clear answer.

Better than getting sick. But how much better?

Better than getting sick. But how much better?

Photographer: Robyn Beck/AFP/Getty Images

Post-infection immunity might be a strange topic for political strife, but it touches on Covid vaccine mandates and whether those who’ve had the virus should be exempt. And so when publications such as The Hill run headlines such as “CDC Finally Recognizing Natural Immunity – Legislators should Follow,” it carries the implication the CDC has been ignoring some long-held scientific evidence. But the science is more complicated and unsettled than that.

The relevant science question isn’t whether natural immunity exists but whether it’s as protective and lasts as long as vaccine-induced immunity. Studies have given conflicting answers. The situation is now changing again, as the BA.2 variant is starting to take over. It’s still considered omicron, but it looks to be wildly different from the version of omicron that’s been dominant, called BA.1.