Cases of Omicron variant XBB are mounting in China, forming a new wave expected to crest around 65 million cases a week by the end of June.XBB, the “first major highly immune-evasive” group of COVID variants, “will sweep through China,” but the wave will be “largely invisible” due to low rates of testing and reporting, Raj Rajnarayanan, assistant dean of research and associate professor at the New York Institute of Technology campus in Jonesboro, Ark., and a top COVID-variant tracker, tells Fortune.When it comes to XBB variants, “the rest of the world has seen them all.” But up until recently,...