What’s the mu variant? And will we keep seeing more COVID-19 variants?

(NewsNation Now) — The World Health Organization has identified another coronavirus variant of interest, calling it the mu variant, saying it may have the ability to evade vaccine protections.

Here’s what you need to know:

What is the mu variant and where is it?

The B.1.621 variant, also known as the mu variant, was first found in Colombia in January 2021 and has been found in about 39 countries so far, including the United States. The variant’s prevalence has “consistently increased” in Colombia and Ecuador, despite reports of sequenced cases dropping globally overall.

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WHO said further studies are needed to determine the characteristics of the mu variant.

Mu has changes, called mutations, which means it might be able to evade some of the protection given from COVID vaccines.

How contagious is it?

One reassuring element is that, despite being around since January 2021, it doesn’t seem to be outcompeting delta, the dominant variant across most of the world. Mu has been designated a variant of interest or VOI by WHO. If there are changes to the virus that means it looks like it has the potential to do more harm, then it is designated as a variant of interest.

WHO’s variants of interest have been determined to exhibit “genetic changes that are predicted or known to affect virus characteristics” including transmissibility, immune escape, disease severity or resistance to treatment. VOIs being monitored by WHO include eta, iota, kappa and lambda.

Mu has yet to be designated as a variant of concern, or VOC, by WHO. If there’s evidence mu is more serious and beginning to overtake other variants such as delta, it might be upgraded to a VOC. Variants of concern worldwide include alpha, beta, gamma and delta.

The Centers for Disease Control and Prevention has also named alpha, beta, gamma and delta as all variants of concern in the United States.

Should I be worried?

If mu was truly as contiguous as the delta variant, we would have expected to have started to see indications of this, and we haven’t yet.

Some mutations will be detrimental to the virus, but some will be beneficial, allowing it to spread better, escape the protection offered by vaccines or even evade COVID tests.

The CDC advised that variants are expected as the pandemic evolves and that receiving COVID-19 shots is still the best way to protect against the virus.

What if mu or another variant doesn’t work with the vaccine?

Most COVID vaccines target the “spike protein” of the virus, which it uses to enter our cells. Our vaccines expose our bodies to a part of the virus, commonly the spike protein, so our immune system can learn to fight the virus off if it encounters it.

If a variant has significant changes in the spike protein, this may decrease the effectiveness of our vaccines.

The WHO said preliminary evidence suggests the mu variant could partially evade the antibodies we get from vaccination. But because this data is from lab studies, we can’t be sure how the variant will actually play out in the population.

More research is needed to be certain about how it behaves in humans, and work on this is ongoing.

The good news is vaccines currently protect well against symptomatic infection and severe disease from all variants of the virus so far.

There’s a probability a new variant that will arise one day that can significantly escape the protection offered by our vaccines, which are based on the original strain of the virus. We would call this an “escape variant”.

However, the leading COVID vaccine manufacturers are well prepared if this eventuates. Some are already developing vaccines for new variants, such as delta.

The Associated Press, Reuters and Nexstar Media Wire contributed to this report.


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