Mu Who? What You Need to Know About the Latest ‘Variant of Interest’

Dr. Anthony Fauci says officials are paying close attention to the Mu variant, but “don’t consider it an immediate threat right now”

As the number of patients hospitalized for COVID-19 continues to drop in Los Angeles County, falling to 1,480 as of Monday, health officials now have their eyes on the latest variant of the virus, which may be more transmissible than other strains and resistant to vaccines.

The Mu variant, which was first identified in Colombia in January, was detected in 167 people over the summer in L.A. County, the Department of Public Health said in a news release. Tests conducted between June 19 and August 21 indicated that Mu was mostly detected during the month of July.

The World Health Organization declared Mu, also known as B.1.621, as a “variant of interest” on August 30, but the U.S. Centers for Disease Control and Prevention has yet to label Mu as a variant of interest, the Los Angeles Times reports. The Delta variant, meanwhile, is considered a “variant of concern,” which means it’s more of a threat; Delta is by far the most dominant strain of the virus at the moment, making up as much as 99 percent of U.S. infections as of September 4, according to CDC data.

County officials report that the Mu variant, which has been detected in 39 countries, “is found to have key mutations linked to greater transmissibility and the potential to evade antibodies.”

“But,” the news release adds, “more studies are needed to determine whether the new strain of interest is more contagious, deadly, or resistant to available vaccines and treatments than other COVID strains.”

Still, Dr. Anthony Fauci, the country’s top infectious disease expert, said during a news briefing last week that Mu is rarely seen in the U.S. and is “not even close” to being the dominant COVID strain.

“We’re paying attention to it,” he said. “But we don’t consider it an immediate threat right now.”

The county’s latest figures, which were last updated Monday, indicate 1,540 new COVID cases and 11 deaths in Los Angeles County.

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