The novel coronavirus first emerged in the Chinese city of Wuhan in late 2019 and was isolated from a patient. The genome sequence of the virus was also sequenced in China and made available to everyone online in early 2020.

At the end of 2021, the world discovered a new mutant strain of the new coronavirus, which the World Health Organization called " Omicron ".

According to Collins Dictionary, the name comes from the fifteenth letter of the Greek alphabet, which the WHO defines as the fifth "variant of concern."

After millions of people were vaccinated with the new crown vaccine , the Omicron variant emerged. People were worried that vaccination would not have the same effect on the new mutants. In fact, this is a reasonable fear, especially because the new mutant strains appeared concentrated in the vaccinated areas. So, what impact has the Omicron spread had for one year? Why is Omicron the most popular strain?

variant strain Source and reason for emergence

The new coronavirus first appeared in Wuhan, China, at the end of 2019. The virus was isolated from a patient. The genome sequence of the virus was also sequenced in China and announced to everyone online in early 2020.

The scientific community and the World Health Organization rely on the Global Influenza Surveillance and Response System used many years ago to store and track the genomes of various virus isolates, which by October 2022 numbered more than 13 million.

This system provides researchers from around the world with the opportunity to study the details of the genomes of viruses isolated from different parts of the world and compare them with the original virus isolated from Wuhan at the outbreak of the COVID-19 pandemic.

From these data it is clear that the viral genome consists of about 30000 units (each unit is called nucleotide ) containing 29 genes responsible for the formation of less than 30 proteins, which of course shows that the viral genome is very small compared to the human genome, which human genome consists of 3 billion units (nucleotides), more than 44 thousand genes and hundreds of thousands of proteins.

When the genome of a new isolate of a virus is compared to the original genome, and there are differences between the new and original genomes, the new isolate is called a "mutant." This difference is due to genetic mutations or errors in the reproduction of the virus and its genetic material to create new viruses in the patient's body.

These mutations or errors occur randomly and, therefore, may occur in any part of the viral genome, negatively or positively affecting its severity, speed of spread, and ability to infect. Therefore, not every change (every mutant) is important or dangerous.

Many mutants and different names

So far, the World Health Organization has detected thousands of virus variants, initially called by the name of the country or city where the variant was first isolated, including the British variant, the South African variant, the Indian variant and the Brazilian variant.

However, this naming method involves a kind of stigmatization of the countries where the mutants appear, so the World Health Organization has adopted a simple naming system, giving each mutant a special symbol for reference and the scientific and medical community, and using another simple name for the media to facilitate communication with the public. The new name

is based on Greek letters and retroactively names variants that existed at the time. For example, the variant that emerged in the United Kingdom was renamed from the British variant to the Alpha variant and received the code (B.1.1.7), while the South African variant was called the Beta variant and received the code (B.1.351).

The World Health Organization divides mutants into several main categories based on their importance:

1. Monitored and tracked mutants: These are mutants that have been proven or expected to be dangerous, including Alpha and Beta variants.
2. Mutants that should be monitored closely: This refers to any mutant with changes in the region of the virus that binds to human cell receptors.
3. Mutants of concern: These are variants that exhibit a higher risk, infectivity, or increased rate of spread.
4. Mutants with severe consequences: These are mutants that exhibit severe consequences, such as those for which known diagnostic methods fail to diagnose them, or for which the vaccine has been ineffective.
5. Other mutants: Any variant that does not fall into the first four categories is usually a harmless variant that has no effect on increasing the risk of the virus and we do not need to monitor it.

Omicron variants A protein with 37 mutations

The fifth variant in the list of mutants of interest, named Omicron and given the code (B.1.1.529), is the first mutant to be named under the new naming system, with previous mutants being named retroactively in the same way.

The first mutated Omicron was isolated in November 2021 from a group of patients from different and distant countries, including countries where infected cases traveled to or from other countries, a list that includes Botswana, South Africa, Hong Kong, Egypt, Belgium, Madagascar and India.

The first thing that draws attention to the potentially huge danger of this mutant is the presence of a very large number of mutations (37 mutations) in the "S" protein responsible for the initiation of infection. This protein binds to specific receptors on the surface of cells in the human respiratory system, from where it begins to penetrate and enter the cells, causing infection.

Preliminary analysis of the new mutant genomes found that 15 of 37 mutations This happened to be located in a region that binds to the specific receptor on the surface of respiratory cells, which raised legitimate concerns about this mutant because the many changes in this region were indicative of two problems:

First, a suggestion that later turned out to be correct was that the Omicron mutant had an increased ability to cause infection due to a greater ability to bind to cell receptors on the surface of respiratory tract cells.

As for the second question, the concern is that widespread changes in the "S" protein may affect the effectiveness of the new coronavirus vaccines currently being administered to millions of people every day, and the purpose of vaccination is to prevent the virus and return life to the way it was before the epidemic.

One year after the emergence of the Omicron variant

On the first anniversary of the emergence of the most important variant of the new coronavirus, Omicron, the World Health Organization released a detailed report.

The report shows that Omicron immediately proved to be more transmissible than its closest variant, the Delta variant (formerly known as the Indian variant), and in less than a month, Omicron spread across the globe, spreading as much as the Delta variant.

At the same time, there has been a significant increase in hospitalizations and deaths from COVID-19, mostly among unvaccinated patients with chronic conditions, but for those who have been vaccinated or have been previously infected, illness has been observed to be less severe than after infection with previous mutants.

During the year, more than 500 new variants from Omicron emerged without a significant increase in disease severity, and at the same time, vaccines proved to be moderately effective in preventing Omicron.

Bivalent vaccines have recently emerged. The first is a vaccine against the original virus, and the second is a vaccine against the Omicron variant.

According to the monitoring and tracking system used by the World Health Organization, the transmission rate of the Omicron variant has reached 100% in some countries and more than 98% in most countries around the world, replacing the original virus and all its other mutants.