The World Health Organization has added the Mu variant, first discovered in Columbia, to its list of variants of interest.
The Mu variant, also known as B.1.621, was first identified in Colombia in January 2021. Since its discovery, the variant has caused multiple outbreaks across South America and Europe. Although the global prevalence of the variant is currently below 0.1%, its prevalence across South America has shown a consistent increase. It currently makes up around 39% of cases in Columbia 13% of cases in Ecuador. As of August 29th, health officials have documented more than 4,500 cases of the Mu variant, from across 39 countries.
In its recent weekly report, the World Health Organization (WHO) updated its variants classification, adding Mu variant to its variants of interest (VOI) list. According to preliminary data, the variant may possess the ability to evade antibodies similar to the Beta variant. However, the report mentions the need for further studies to confirm these findings.
What is a Variant of Interest?
As per WHO’s definition, a variant of interest is a SARS-CoV-2 variant with genetic changes that can affect the virus’s transmissibility, severity, immune escape, and diagnostic or therapeutic escape. Moreover, the variant must have caused multiple outbreaks or sporadic cases across multiple countries. According to the WHO, the Mu variant fits the definition; thus, warranting an update to their list.
However, the VOI is not to be confused with a variant of concern (VOC). There are currently four designated VOCs: Alpha, Beta, Gamma, and Delta. These variants are far more dangerous and have shown a significant effect on global public health measures.
As the deadly Delta variant continues to circulate in South America, health officials are keeping a close eye on the Mu variant.
Reference: World Health Organization