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The BA.2 subvariant of Omicron accounts for over half of new U.S. coronavirus cases, the C.D.C. estimates. (Published 2022)
Scientists have been keeping an eye on BA.2, one of three genetically distinct varieties of the Omicron variant of the coronavirus.
The highly contagious Omicron subvariant known as BA.2, which led to a surge of coronavirus cases in Europe, is now the dominant version of the virus in new U.S. cases, according to estimates from the Centers for Disease Control and Prevention on Tuesday.
Last week, the World Health Organization reiterated that BA.2 was the dominant version of Omicron around the world, and Dr. Rochelle Walensky, the director of the C.D.C., said she anticipated it would soon become dominant in the United States.
Scientists have been keeping an eye on BA.2, one of three genetically distinct varieties of the Omicron variant of the coronavirus, which was discovered by South African researchers in November.
BA.2 was first identified in the United States in December, and it accounted for about 55 percent of new U.S. cases in the week ending Saturday, according to C.D.C. estimates on Tuesday.