If things stay quiet, as some models predict , it will mark the first time a viral strain has taken over in the US without causing an increase in Covid-19 cases. He says cases in the US were coming down faster and fell farther before BA.2 outgrew its Omicron cousin here. Zooming in on areas of the country that are seeing more BA.2 transmission, like New York, wastewater has been only modestly affected. San Francisco is also seeing signs that BA.2 may be making a move, but it hasn't been a major one. "That data, to me, would say that, you know, they had a smaller Omicron wave, and now [BA.2 is] picking up," she said.

Source: CNN April 08, 2022 19:54 UTC