Delta now dominant coronavirus variant in U.S.

Delta now dominant coronavirus variant in U.S.

A highly contagious variant of the novel coronavirus that was initially identified in India is now the dominant strain in the United States, according to the Centers for Disease Control and Prevention.

Data updated by the CDC on Tuesday evening shows the so-called delta variant, also known as B.1.617.2, was estimated to account for 51.7% of all new cases of COVID-19 across the country as of July 3.

The variant, which has been detected in all 50 states, was also estimated to account for more than 50% of new cases in five of the 10 regions into which the U.S. Department of Health and Human Services divides the country. HHS Region 7 - comprised of Iowa, Kansas, Missouri and Nebraska - had the highest at 80.7%.

"Variant proportions are dynamic and difficult to predict due to reporting delays, the presence of multiple variants, and changing incidence," the CDC told ABC News in a statement on Tuesday evening.

A little over a month ago, CDC data showed the delta variant was estimated to account for just 3% of all new cases in the U.S.

After being initially identified in India in October, the delta variant has since been reported in at least 98 countries around the globe, according to the World Health Organization. It was first detected in the U.S. in March.

Since the start of the pandemic, the U.S. has reported more than 33.7 million confirmed cases of COVID-19 and over 605,000 deaths from the disease, according to data collected by Johns Hopkins University.

More than 182 million people in the U.S. have received at least one dose of a COVID-19 vaccine, including over 157 million - 47.5% of the population - who are fully vaccinated, according to the CDC.