A Covid Mystery

David Leonhardt: “To many people’s surprise — including mine — new Covid-19 cases in the U.S. have not begun to rise. Over the past two weeks, they have held roughly steady, falling about 1 percent, even as the highly contagious BA.2 subvariant of Omicron has become the dominant form of Covid in the U.S.”

“Across much of Europe, by contrast, cases surged last month after BA.2 began spreading there, and many experts expected a similar pattern here. That hasn’t happened.”