US reports over 20,000 coronavirus variants infections - China.org.cn

The United States has recorded more than 20,000 infection cases of coronavirus variants as of Thursday, according to the latest data of the U.S. Centers for Disease Control and Prevention (CDC).

The majority of those variants cases, 19,554 cases were caused by the variant known as B.1.1.7, which was originally detected in Britain.

There were 424 cases of a new strain initially discovered in South Africa, called B.1.351, and 434 cases of the P.1 strain first discovered in Brazil.

In addition, the B.1.427 and B.1.429 variants, two coronavirus strains first detected in the U.S. state of California, are also being closely monitored by the CDC.

The five coronavirus strains are currently classified by the CDC as "variants of concern," as evidence shows an increase in their transmissibility, increased hospitalizations or deaths, reduced effectiveness of treatments or vaccines, and diagnostic detection failures.

Even as the country picks up its COVID-19 vaccination pace, the coronavirus variants are spreading rapidly, and experts warn the variants infections could potentially stall the nation's recovery from the pandemic.

The B.1.1.7 variant is "now the most common lineage circulating in the United States," said CDC Director Rachelle Walensky on Wednesday.