Fauci Says Prevalence of New Mu Variant 'Extremely Low' in U.S.

New variants of the coronavirus are continuing to pop up, but the nation's top infectious disease expert says the number of circulating cases made up of these strains remains "extremely low," especially in comparison to the tremendous dominance of the Delta variant.

"The prevalence of the Mu and the C.1.2 variant is extremely low in the United States—0.5 percent for Mu and nothing for the C.1.2—because the Delta variant continues to dominate," Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, said at a Friday news briefing.

The Mu variant, which has now been detected in every state but Nebraska, has recently caught the attention of many researchers and doctors.

Last month, the World Health Organization (WHO) labeled Mu as a "variant of interest" after preliminary data indicated it could be more easily transmitted and more resistant to vaccines than the original strain of the virus.

The Mu variant was first identified in Colombia in January. It has since become the dominant strain of the virus in several countries in South America.

Anthony Fauci Mu Variant Extremely Low COVID
Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases, called the prevalence of the Mu variant and the C.1.2. variant of the coronavirus "extremely low" in the U.S. Above, Fauci arrives to testify before the Senate Health, Education, Labor, and Pensions Committee on July 20, 2021, in Washington, D.C. Stefani Reynolds/Getty

Dr. Nick Gilpin, Medical Director of Infection Prevention for Beaumont Health, previously told Newsweek that the new variant "has certainly kind of gotten our attention," but noted that for many doctors, mutations of COVID-19 were expected.

The C.1.2 variant, which has yet to be given a Greek letter determination, has also drawn attention since being identified in South Africa in May. It has not been labeled as a variant of interest or variant of concern by WHO yet.

Mutations to the original strain of the coronavirus have put experts on high alert due to the rapid spread some variants, like Delta, have had.

In June, the Delta variant represented 13 percent of cases in the U.S. Currently, it makes up nearly 99 percent of all cases in the country.

On Friday, federal officials said the C.12 variant has not yet been identified in the U.S., while data from the Centers for Disease Control and Prevention (CDC) shows that the Mu variant only accounts for 0.1 percent of circulating cases at this time.

Fauci said the variants were first brought to his attention because they "had a number of mutations that were of interest," but he reiterated that looking at the effect the COVID-19 vaccines had on the variants, "it is not a matter of alarm."

"As always, we will continue to closely monitor these and other emerging variants, but the most important thing we can do to protect against any variant, be it Delta, Mu or C.1.2 is to get vaccinated," Fauci said during the White House's weekly COVID-19 briefing.

Even though new variants have led to an increased number of breakthrough infections, experts have continued to urge unvaccinated people to get their shots.

While the Delta variant has infected vaccinated individuals, the vaccines have been shown to prevent severe illness and hospitalizations.

"We're getting a vaccine that protects us beautifully from the original strain—maybe not as well from some of these variants, but does that meant the vaccines are no good? Absolutely not," Stanford's Dr. Bali Pulendran previously told Newsweek.

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