The World Health Organization (WHO) has added another variant of the coronavirus to its list to watch. It is called mu and it has been designated as a variant of interest (VOI).
This means that it has genetic differences with the other known variants and is causing infections in multiple countries, so it could pose a threat particular for public health.
It is possible that mu’s genetic changes make it more transmissible, allow it to cause more serious disease and make it better able to escape the immune response elicited by vaccines or infection with earlier variants.
This, in turn, could make it less susceptible to treatments. Note the word could.
A VOI is not a variant of concern (VOC) , which is a variant that has been shown It takes on one of those characteristics, which makes it more dangerous and therefore more important.
Mu is being closely watched to see if it should be designated as a VOC. Hopefully it isn’t.
There are four other VOIs that are being watched by WHO – eta, iota, kappa and lambda – but none of them have been reclassified as VOC.
That could be the case for mu as well, but we have to wait for more data.
What makes mu What is particularly interesting (and concerning) is that it has what the WHO calls a “constellation of mutations that indicate potential immune escape properties.”
In other words, it has the distinctive traits of being able to circumvent existing vaccine protection.
Where is it spreading?
Mu was seen for the first time in Colombia in January of 1982, when given the designation B. 1621. Since then it has been detected in 40 countries, but is currently believed to be responsible for only 0.1% of infections globally.
Mu has been much more prevalent in Colombia than anywhere else.
If the coronavirus samples that have been genetically sequenced are observed, the 39 % of the analyzed in Colombia have been of mu —although no samples have been recorded there in the last four weeks—.
On the contrary, the 13% of the samples analyzed in Ecuador have been mu, and this variant represents 9% of the samples sequenced in the last four weeks, while in Chile slightly less than 40% of the samples sequenced have turned out to be so in the last month.
This suggests that the virus no longer circulates in Colombia , but is transmitted in other nearby South American countries.
So far, they have been identified 45 cases in the UK using genetic testing, and appear to be from abroad.
However, as not all cases of covid – 19 end up being sequenced to see which variant they are, it is possible that the prevalence of mu in the United Kingdom is higher .
How dangerous is it?
The questions key is whether mu is more transmissible than the currently dominant variant, delta, and whether it can cause more severe disease.
Mu has a mutation call P 681 H, first reported in the alpha variant, which is potentially responsible for faster transmission.
However, this study is still in progress. prepublication format, which means that its conclusions have not yet been formally reviewed by other scientists.
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We still can’t be sure of the effects of the P 681 H in the behavior of the virus.
Mu also has the mutations nes E 417 K and K 417 N, which are associated with the ability to evade antibodies against the coronavirus. The evidence on this is more concrete.
These mutations also occur in the beta variant, so it is possible that mu behaves like beta, against which some vaccines are less effective.
Mu also has other mutations, such as R 346 K and Y 144 T, the consequences of which are unknown, hence the need for further analysis.
But can the mu evade really pre-existing immunity?
There is only limited information on this so far, with a study from a laboratory in Rome showing that the Pfizer / BioNTech vaccine was less effective against mu compared to other variants when tested in a laboratory experiment.
A Despite this, e The study still considered the protection offered against mu by the vaccine to be robust. Actually, we still don’t know if mu mutations will result in increased infection and disease.
Yet surprising reports have surfaced about a lot.
In late July, a Florida news channel reported that the 10% of the samples sequenced at the University of Miami were mu.
In early August, Reuters reported that seven fully vaccinated residents of a nursing home in Belgium had died from an outbreak of mu.
However, these are limited snapshots of the variant’s behavior .
What will happen next?
Mu is the first new variant to be added to the WHO list since June.
When a variant of interest is designated, WHO leads to carry out a comparative analysis of the characteristics of the new variant, evaluating how it compares with others that are also being monitored, asking its member states to collect information on the incidence and effects of the variant.
This is currently being carried out.
The designation of mu as VOI reflects widespread concern about the possibility of new variants emerging that could be problematic.
The delta variant, more transmissible, which is taking hold in many countries, especially among the unvaccinated, shows the speed and importance with which viral variants can change the course of the pandemic.
Every time the virus reproduces inside a person there is the possibility that it mutates and a new variant appears.
It’s a numbers game. It’s a random process , a bit like rolling the dice.
The more spins there are, the greater the chance that new variants will appear. The main way to stop the variants is global vaccination.
The appearance of the mu reminds us how important it continues to be that goal.
Many people, especially in developing countries, remain unvaccinated.
We must get the vaccines to these countries as soon as possible, both to help vulnerable people there and to prevent new variants from emerging.
Otherwise, our exit from the pandemic will be delayed, possibly for months.
Luke O’Neill is Professor of Biochemistry at Trinity College of Dublin, Ireland.
This article was published in The Conversation. Click here to access the original.
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