Delta variant now accounts for over 93% of all U.S. Covid cases

ATLANTA, Georgia -- The highly-infectious Delta variant now accounts for an estimated 93.4% of all coronavirus cases now occurring in the United States, according to figures published by the U.S. Centers for Disease Control and Prevention on Wednesday.

This includes several sub-lineages of Delta, all of which are classified as variants of concern. Together, they made up about 93.4% of cases during the last two weeks of July.

This number is even higher in certain parts of the country, including the region that includes Iowa, Kansas, Missouri and Nebraska, where Delta accounts for more than 98% of circulating virus.

These figures have shown a rapid increase over the past two months. In the two weeks ending May 22, for example, Delta's prevalence was estimated around 3%.

At that same time in May, another variant first identified in the United Kingdom – Alpha, or B.1.1.7 – was the dominant one in the U.S., causing 69% of cases. Now, the CDC's most recent estimates put that variant at just under 3%.