Amid the continued spread of the coronavirus' Delta variant, a new strain, the Mu variant, begins its spread across the United States, causing concerns as it is believed to be resistant to vaccines and also highly transmissible.

This week, the World Health Organization (WHO) announced that the new COVID-19 variant accounts for a small percentage of all coronavirus cases in the U.S. So far, Illinois has only recorded 18 cases of the new strain.

New COVID-19 Variant

Citing Colombia, where the new variant was first detected in January, the WHO revealed that the strain has already spread so far in the region, accounting for 39% of all coronavirus cases. The new strain was also reported in 38 other countries worldwide.

The research assistant professor of medicine at Northwestern University Feinberg School of Medicine, Ramon Lorenzo-Redondo, said that Colombia's number could be misleading. The medical expert said officials from the country have conducted few genetic examinations of its virus cases, which means that the high percentage of Mu variants could be false, the Chicago Tribune reported.

However, a Colombian epidemiologist, Elena Navas-Nacher, who founded the Global Health Beat Foundation based in Chicago, said the Mu variant has taken a great toll on the country. She said that intensive care units in the region were 90% full when she visited this summer.

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U.S. officials said they were keeping a "very close eye" on the new Mu variant because of its potential to be resistant to the COVID-19 vaccines. The nation's top infectious disease expert, Dr. Anthony Fauci, who is also the director of the National Institute of Allergy and Infectious Diseases, said the government was taking the new strain very seriously.

The medical expert said that while the new variant has been recorded in the country, it has not yet shown the level of dominance that the Delta variant has exhibited. The new variant, which is also known as B.1.621, has mutations that allow it to evade certain antibodies, which could include those from the vaccines, CBS News reported.

Not an Immediate Threat

However, Fauci said there was not enough clinical evidence to support the hypothesis, arguing most of it was laboratory vitro data. The WHO previously designated the Mu strain as a "variant of interest," arguing more extensive studies need to be conducted to confirm whether or not it could actually evade existing antibodies.

"We're paying attention to it, we take everything like that seriously, but we don't consider it an immediate threat right now," Fauci said during a White House COVID response news briefing on Thursday.

The infectious disease expert said that even at times where a variant reduces the efficacy of the vaccines, the treatments are still quite effective against the viruses of those times. During the briefing, Fauci also noted that he would not be surprised if the current COVID-19 vaccines would soon require three doses of the shots.

As an immunologist, he said that the full regimen for vaccination would likely become three doses. Fauci said it could become the routine regimen and said other officials will be responsible for determining how many doses of the vaccine should be administered, Fox News reported.

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