Highly immune evasive omicron XBB.1.5 variant is quickly becoming dominant in U.S. as it doubles weekly- The Covid omicron XBB.1.5 variant has nearly doubled in prevalence over the past week and now represents about 41% of new cases in the U.S., according to CDC data.XBB.1.5 now represents about 41% of new cases nationwide in the U.S., nearly doubling in prevalence over the past week, according to the data published Friday by the Centers for Disease Control and Prevention.Andrew Pekosz, a virologist at Johns Hopkins University, said XBB.1.5 is different from its family members because it has an additional mutation that makes it bind better to cells.Yunlong Richard Cao, a scientist and assistant professor at Peking University, published data on Twitter Tuesday that indicated XBB.1.5 not only evades protective antibodies as effectively as the XBB.1 variant, which was highly immune evasive, but also is better at binding to cells through a key receptor.Scientists at Columbia University, in a study published earlier this month in the journal Cell, warned that the rise of subvariants such as XBB could "further compromise the efficacy of current COVID-19 vaccines and result in a surge of breakthrough infections as well as re-infections.""