More than a year has passed since the omicron version of SARS-CoV-2, the virus that causes COVID-19, first appeared. Prior to omicron’s ascendancy, there had been a rapid succession of designated variants of concern, including alpha, beta, gamma, and delta.
The offspring and grandchildren of omicron appear to be represented by an endless stream of letter and number combinations: BA.2, BA.2.75, BA.5, BQ.1, BF.7, XBB – the list goes on.
What is required for a new variety to receive a Greek letter as a name, and will omicron ever be replaced?
As background, in May 2021, the World Health Organization (WHO) announced that important strains of SARS-CoV-2 would receive Greek names in addition to their scientific designations.
The objective was to provide the public with an easy way to discuss them and to prevent stigma.
Previously, SARS-CoV-2 variations were referred to based on where they were initially found.
When a virus like SARS-CoV-2 replicates, it creates identical copies of itself. This procedure is analogous to copying a document without a spell checking; it results in misspellings.
These errors may affect the amino acids that comprise a protein, hence altering its structure or function.
These proteins form either the structural architecture of a virus or a portion of the replication machinery required by the virus.
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Typically, these errors or “mutations” in the virus’ design or machinery damage it. Occasionally, though, they make the virus more capable of causing sickness, spreading, or evading our immune system.
When viruses with the same set of typos are discovered in a sufficient number of hosts, this group is known as a variation.
As long as SARS-CoV-2 continues to spread, it will continue to evolve and produce new variations.
SARS-CoV-2 variations with the potential to be more transmissible, better evade our immune system, or cause more severe disease are identified by genetic surveillance.
These are categorized as variants of concern or variants of curiosity. To date, the WHO has identified five variations with Greek letter names as being of concern.
WHO classified B.1.1.529 as a variation of concern on November 26, 2021, and termed it omicron.
In comparison to alpha and delta, omicron exhibited a dramatic shift in the virus’ evolution, with twice as many mutations in the spike protein (a protein on the surface of SARS-CoV-2 that lets it to adhere to our cells).
The World Health Organization (WHO) designated omicron as a variation of concern due to its substantial genetic mutation and increased capacity to spread between humans and escape immunization.
Currently, only the omicron form is infecting humans. The variations alpha, beta, gamma, and delta are now categorized as “previously circulating.”
Although there are genetic distinctions between omicron’s offspring, such as BA.2 and BA.5, and its grandkids, XBB and BQ.1, they are all quite similar to one another and to the original omicron strain.
Because of this, they are considered descendants of omicron rather than different varieties.
Some scientists have stated that, from the perspective of public messaging, this system should use a rethink.
Specifically, they suggest that the high threshold imposed by the WHO for novel variants of concern should be decreased in order to allow the public to track the ongoing evolution of COVID.
Omicron’s sustained dominance is partly because to its enhanced capability for human-to-human transmission and its ability to elude previous immunity to infection and vaccination.
It is difficult for a considerably distinct virus to compete and establish itself against omicron.
Scientists throughout the world continue to watch the growth of SARS-CoV-2 despite the fact that testing and monitoring activities have been reduced.
The next variety of concern will be denoted by the Greek letter pi, which follows omicron in the alphabet.
For pi to be classified, there must be a substantial genetic sequence variation between it and omicron, and the variant must be significantly more infectious or cause a more severe disease.
This novel pi variety could have originated from animals. While there are few recorded incidences of animals transmitting COVID to humans, different host species can facilitate the development of different mutations.
Pi may also occur in immunocompromised hosts.
SARS-CoV-2 has showed the ability to rapidly mutate in clinically vulnerable individuals whose immune systems have difficulty clearing the virus, allowing it time to accumulate a large number of mutations.
SARS-CoV-2 undergoes the same evolution as all other viruses. More strains of illness will certainly be identified, although this trend will likely slow.
WHO’s technical head on the COVID pandemic, Maria Van Kerkhove, has previously suggested that whenever we run out of Greek letters, additional variations may be named after star constellations.
This has not been officially verified, but we do know that it is unlikely to occur in the near future.
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