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There is no anomaly in the emergence of a new strain. The occurrence of mutations is a natural process for all living systems. It is associated with the copying of genetic material, in this case the RNA of a virus. Such copying is associated with the occurrence of errors, that is, mutations. We simply do not notice most of these mutations, because their carriers turn out to be less adapted than the original variants. In the case of viruses, the number of viral particles in an infected person, for example, is so enormous that there is always some possibility that slightly improved variants will arise relative to the original virus that infect the person. If this option has a significant advantage, it begins to increase its frequency, displacing the original one. This is a natural process that will never end.
How dangerous the omicron can be – time will tell. In a couple of weeks, it will become clear how effectively this virus is neutralized by antibodies that arise when vaccinated with available vaccines. Within a few months, it will become clear whether it is capable of increasing its frequency, displacing delta, in the way that delta previously supplanted other options. This will clarify its epidemiological significance. Clinical observation of people with confirmed cases of infection with the new strain will allow to assess whether the severity of the disease is increased. It is not yet clear whether there will be significant changes in any of these indicators.
The presence of such a large number of mutations allows us to make assumptions about the origin of the virus. Multiple mutations must occur sequentially: first there is one change in the genetic text, then such a virus, having gained some advantage, spreads, then against the background of the existing mutation a second appears, then a third, a fourth … That is, there is a sequential accumulation of mutations over time. In this case, for a new variant, which contains more than 50 substitutions relative to the Wuhan virus, we can expect that we could see intermediate variants with two, three, five, six, forty, forty-five, and finally fifty changes. But no such intermediate forms have been found. Many expected that new variants of the virus would emerge against the background of the delta, that is, such a super-delta with additional mutations would appear, because this is now the main variant – 99% of all infections occur due to the delta. But the omicron, obviously, is not a superstructure over the delta, it arose independently, suddenly and as if from nowhere. Apparently, such a large number of mutations in this new variant accumulated during a long-term infection of one person, most likely with a suppressed immune system.
In a long covid situation, the infected person becomes a “bulb” in which the evolution of the virus takes place. The immune system cannot completely fight the infection, but the person does not die. For the epidemiological process, the death of an infected person or his recovery is one and the same. And in a person who is ill for a long time and develops some kind of partial immune response, conditions are created for the selection of new variants of the virus. In the course of a long infection, the virus changes, slowly acquiring more and more new mutations that allow it to exist in the body of an infected person for a long time, gradually adapting to the immune response. Ultimately, the resulting variant with multiple mutations comes out, infects other people, and can begin to spread. This is what the omicron seems to have happened. Of the 50 mutations in this virus, not all alter proteins. However, some of the mutations actually affect the S-protein, through which the coronavirus interacts with our cells. Our immune system also recognizes the virus by interacting with this protein. Therefore, Most likely, the new variant has changed some parameters of the infection and, possibly, the ability to escape from the immune response is improved. But this is not certain, at least not yet.
Modification of a new generation of vaccines, that is, vector vaccines like AstraZeneca or Sputnik V, or RNA vaccines like Moderna and Pfizer, is a piece of cake. Doesn’t take much time. But it is not at all obvious that this should be done. For example, no one made new vaccines for the delta. Another issue is that changes in vaccines will then require the creation of an evidence base, clinical trials, which would demonstrate that the new product really has improved properties in relation to the new variant of the virus. At the moment, there is no need for this. And despite the large number of mutations, there is no doubt that there will be an immune response to the new strain.
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