The World Health Organization (WHO) has added the COVID variant "Mu" to its variants of interest watchlist after fears that the virus strain could resist immune defenses provided by vaccines.

WHO said the "Mu" variant, also known as B.1.621, was added to its watchlist after it was detected in 39 countries and for its certain worrisome features, The Blaze reported.

According to the agency's health bulletin, the Mu variant has a constellation of mutations with possible immune escape properties.

Early data shows that the variant may evade or be resistant to vaccine immune defenses, similar to the Beta variant. However, more studies are still needed to confirm the theory.

The WHO noted that its increasing prevalence in Colombia and Ecuador was a cause for continued monitoring despite declining global prevalence.

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Mu COVID Variant

The Mu variant was first discovered in Colombia in January 2021. Cases of the variant have also been reported in the U.K., Europe, U.S., and Hong Kong.

The Guardian reported that it was gaining ground in Colombia and Ecuador, with 39 percent and 13 percent prevalence, respectively.

At least 32 cases of the Mu variant were found in the U.K. A Public Health England report noted that most of the cases were found in London in July, with most of the infected people in their 20s.

In addition, some of those people who tested positive for the Mu variant received one or two doses of the COVID vaccine. The WHO said the Mu variant would be monitored for any changes.

In the U.S., Mu seems to be most prevalent so far in Florida, particularly in the Miami area with the frequent travel in those areas, Fortune reported.

The Centers for Disease Control and Prevention (CDC) has also identified the Mu variant as a variant of interest. However, it has not yet moved it to the level of a variant of concern.

The European Center for Disease Control and Prevention also recognized that it could have a significant impact. It added that the data is still early to confirm.

COVID Vaccine Effectiveness

Pfizer's vaccine effectiveness had declined over time, with about 84 percent for vaccinated people in four to six months after getting their second dose, according to company CEO Albert Bourla.

Pfizer's vaccine was strongest at 96.2 percent, which was noted between one week and two months after receiving the second dose, according to CNBC.

The Pfizer CEO said they had seen data from Israel showing a decline in immunity. The decline has affected what used to be what was 100 percent against hospitalization. He added that after six months, the vaccine's effectiveness declined to the 90s and mid-to-high 80s.

The Pfizer CEO noted that the company is planning to formally send data to U.S. regulators about the pros of a third COVID vaccine dose by mid-August.

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This article is owned by Latin Post

Written by: Mary Webber

WATCH: World Health Organization is Monitoring a New COVID Variant Called 'Mu' - From WXYZ-TV Detroit Channel 7