Katherine J. Wu, Ed Yong, and Sarah Zhang write:

For nearly two years now, Americans have lived with SARS-CoV-2. We know it better than we once did. We know that it can set off both acute and chronic illness, that it spreads best indoors, that masks help block it, that our vaccines are powerful against it. We know that we can live with it—that we’re going to have to live with it—but that it can and will exact a heavy toll.

Still, this virus has the capacity to surprise us, especially if we’re not paying attention. It is changing all the time, a tweak to the genetic code here and there; sometimes, those tweaks add up to new danger. In a matter of weeks, the Delta variant upended the relative peace of America’s early summer and ushered in a new set of calculations about risk, masking, and testing. The pandemic’s endgame shifted.

Do vaccines work as well as they need to? Who is now most vulnerable? What new variants might emerge? Our lost summer has layered on new anxieties to pandemic life. But these questions do have some clear answers, which have come up time and again in our reporting and will continue to guide us through the coming months. Even after this latest surge crests and subsides, the new pandemic reality will linger, through fall and winter and into the spring, as vaccination rates rise and the virus continues to change. Here are six principles that are helping us make sense of the pandemic now: [Continue reading…]