Context: WHO has classified yet another SARS-CoV-2 variant “B.1.621” as a variant of interest (VOI) and given it the label “Mu”.
About
The variant was first identified in Colombia in January, 2021.
The global prevalence of the Mu variant among sequenced cases has declined and is currently below 0.1%. However, prevalence in Colombia (39%) and Ecuador (13%) has consistently increased.
Larger outbreaks were reported from countries in South America and Europe.
Cases have also been reported in the UK, US and Hong Kong.
Classes of SARS-CoV-2 variants
Variant of Interest
A variant with specific genetic markers that have been associated with changes to receptor binding which affect its diagnosis and are expected to cause unique outbreak clusters.
It is known for it predicted increase in transmissibility.
It is classified based on factors such as genetic changes that are predicted or known to affect virus characteristics such as transmissibility, disease severity, immune escape etc.
It represents a lower level of concern than a variant of concern (VOC).
Variant of Concern
A variant for which there is evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths).
It is known for its significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.
Example – Alpha, Beta and Delta variants of SARS-CoV-2.
