delta variant

Delta, a ‘Variant of Concern,' Accounts for 10% of New US Cases: CDC

The change in classification is based on mounting evidence that the variant spreads more easily and causes more severe disease

electron micrograph
BSIP/Universal Images Group via Getty Images

The so-called delta variant of the coronavirus now accounts for nearly 10 percent of new cases in the United States, the Centers for Disease Control and Prevention said Tuesday.

The agency on Monday declared the variant, which was first detected in India, a "variant of concern," a designation given when there is increased evidence of factors such as transmissibility or severity or reduced effectiveness of vaccines or treatments.

The change in classification "is based on mounting evidence that the Delta variant spreads more easily and causes more severe cases when compared to other variants, including B.1.1.7 (Alpha)," the CDC said in a statement to NBC News. The alpha variant was first detected in the United Kingdom, and in April, it became the dominant strain in the U.S.

Coronavirus Pandemic

Full coverage of the COVID-19 outbreak and how it impacts you

California Man Who Mocked COVID-19 Vaccine Dies of Virus

DOJ Says No Probe Into State-Run Nursing Homes in New York

Read the full story at NBCNews.com.

Contact Us