A new Omicron subvariant made up nearly 60 percent of all new U.S. cases in the latest week, according to estimates released by the U.S. Centers for Disease Control and Prevention (CDC) on Tuesday.
The new subvariant, known as BA.2.12.1, spreads more rapidly than previous versions of Omicron.
It only made up about 3.4 percent of new COVID-19 cases in the country in late March. The data increased to 31.8 percent at the end of April, and 59.1 percent the end of May, CDC data showed.
The new version evolved from BA.2, which was more contagious than any previous coronavirus variant.
The United States is averaging more than 100,000 new confirmed cases per day, according to CDC data. Health experts are predicting sharp rise of new infections after Memorial Day weekend travels and gatherings.