What is the Mu variant of the coronavirus?
The World Health Organization (WHO) this week named a new "Variant of Interest" of the coronavirus. It is known as the Mu or B.1.621 variant. It has several significant mutations, implying it might be able to bypass protection from prior infection or COVID-19 vaccination. However, its prevalence around the world remains relatively low. Here's what we know about it so far.
When and where did it originate?
The Mu variant was first detected in the South American country of Colombia in January this year and has since spread to about 39 countries. As of late August, more than 4,500 sequences have been designated as Mu in the past four weeks. Most of them were reported in the United States (2,065), followed by Colombia (852), Mexico (357), and Spain (473).
Mu's prevalence is high in Colombia, Ecuador: WHO
"Although the global prevalence of the Mu variant among sequenced cases has declined and is currently below 0.1%, the prevalence in Colombia (39%) and Ecuador (13%) has consistently increased," the WHO said.
What is a Variant of Interest?
Variants of Interest are those found to cause community transmission in multiple clusters but not necessarily more virulent or transmissible. Apart from Mu, four other Variants of Interest named by the WHO include Eta, Iota, Kappa, and Lambda. If there's enough evidence that Mu is more dangerous and/or begins to overtake other variants like Delta, it may be upgraded to a Variant of Concern.
Can it escape vaccine immunity?
A WHO report cites preliminary data to suggest that Mu may be able to evade immunity generated from both past infection and coronavirus vaccination. However, the health agency notes that more studies are needed to draw such a conclusion. Meanwhile, an assessment by Public Health England (PHE) said the strain is at least as resistant as the Beta variant to vaccine-generated protection.
Vaccines may not provide protection forever
It is likely that a new variant may emerge in the future that can significantly escape the protection offered by vaccines. That's because the current vaccines were developed to target the original strain of the virus. However, the silver lining is some vaccine makers are working to develop shots for new variants or are able to alter their vaccines to match the new strains.
