The highly contagious Omicron BA.5 subvariant has become the dominant version of the virus causing new cases of Covid-19 in the US, the latest federal data show.
BA.5 accounted for nearly 54% of U.S. cases in the week ending July 2, the Centers for Disease Control and Prevention estimated on Tuesday. It surpassed BA.2.12.1, the version of Omicron partly responsible for a persistent spring increase in cases, which is now estimated to represent closer to one in four cases.