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Scientific treatment of COVID-19 virus mutation
Scientific treatment of COVID-19 virus mutation. What is the mutation of the new coronavirus, how is the mutation currently diagnosed, whether the infectiousness of the disease has increased, and whether the new coronavirus vaccine that has been developed in many countries is still effective.
Since many countries have reported the discovery of mutated new coronaviruses (such as 501.V2 and VUI-202012/01 mutated viruses), the virus mutation has caused heated discussions among the people. In this issue, we will provide answers to several aspects such as what is the mutation of the new coronavirus, how the mutation is currently diagnosed, whether the infectiousness of the disease has increased, and whether the new coronavirus vaccine that has been developed in many countries is still effective.
1. What is the COVID-19 mutation?
Viral mutation refers to changes in the genetic material of the virus caused by various reasons, such as base mutations in its genetic material DNA/RNA. Various factors such as chemistry and physics can induce various mutations. These mutations are often beneficial to viruses. For example, HIV-1 virus has a mutation rate of 1 in 30,000, and such high mutations often lead to changes in drug resistance. , Causing increased difficulty in treatment and weakening of vaccine protection.
As the simplest living organism, viruses are more prone to mutation due to their simple structure of genetic material. These mutations mainly occur in the process of genome proliferation and replication. Due to immune pressure (such as changes in the cellular immune microenvironment where the virus exists) or the characteristics of the virus itself (such as errors in the replication and shearing of genetic material, lack of precise replication capabilities), mutations occur all the time. Therefore, mutation can be said to be a strategy or way of survival for viruses to respond to environmental choices. This mutation is long and slow in the natural environment (such as the formation of new quasispecies) and can be accelerated with the increase of environmental pressure.
The coronavirus (Sars-CoV-2) has changed once or twice a month since the beginning of the pandemic. This time, the new mutation (B.1.1.7) in the United Kingdom has a faster gene mutation rate. There are a total of many different gene mutation points in the genetic code of this virus’s new mutation, including 6 synonymous mutations, 3 deletion mutations and 14 non-synonymous mutations, and its evolution is farther than the root.
Among them, 8 gene mutation points occurred on the spike protein, the important structural protein of the virus. It is worth noting that the 501Y.V2 mutation occurs in the RBD receptor binding region, which leads to a tighter binding to the human cell receptor ACE2.
WHO has also reported several other variants such as D614G, which can make the virus more contagious; the mink-related variant “Cluster 5” may be related to the reduction of natural infections or the scope of immune protection after vaccination. It is related to duration. VOC 202012/01 variant, it can make the virus more contagious.
What kind of environmental changes made this virus mutation appear? According to “Science”, immune vulnerable people may be the key to major mutations in the new coronavirus. These people with vulnerable immune systems may provide opportunities for the evolutionary lineage of the new coronavirus, and the mutation of the new coronavirus will also aggravate the primary diseases of this population.
2. New coronavirus, talk about mutation and discoloration?
The new mutation of this virus has been detected in many countries, but is there no virus mutation in countries that have not reported it. For example, the United States has not yet reported the occurrence of a mutated virus, but it is not that the virus mutation does not exist in this area, because the detection and determination are limited by the detection methods and the strength of the detection.
Compared with influenza, which is also a respiratory virus, the new coronavirus has a slower rate of change, so new influenza vaccines need to be introduced every year. However, there are two worries about this mutation. The first is that a large number of mutation sites have been detected, and the second is that these mutations all occur in its important structural protein, the spike protein. Compared with the previous mutation of the new coronavirus, the scope of the spread of this mutation is also wider.
The report pointed out that the British variant has 70% higher transmission than the original strain, and the binding rate of S protein to human ACE2 receptor has also increased by 100 times. It is worth pointing out that the accuracy of the data still needs more epidemics. The results of scientific investigations are accurate, and more laboratory cell experiments and animal experiments are needed to further confirm its infectivity.
Does the virus mutation cause the disease to worsen? So far, the new mutation of the new coronavirus does not seem to cause the infected person to have more severe illness than the previous virus infection. There is no evidence to prove that the new mutation of the virus is more deadly. This aspect still needs more research.
At present, even if the new mutations of these viruses are truly more infectious, the overall course of the epidemic will not change as a result. At least, as China continues to strictly prevent and control the epidemic, its impact on the overall progress of the epidemic is still optimistic. The overall course of the epidemic is also affected by many reasons, including the protective measures in the public health strategy and the promotion of vaccines. Therefore, the people do not need to panic while not taking it lightly.
3. How is the mutation of the new coronavirus diagnosed?
First of all, the current mainstream nucleic acid detection reagents in China are aimed at dual target genes, namely N gene and ORF1ab gene, which are more effective than single target gene amplification. The S protein gene mutation of this new mutant strain currently emerging in the UK, and the surviving detection methods will not affect the sensitivity and specificity of nucleic acid reagents.
During the COVID-19 pandemic, scientists from various countries sequenced the Sars-CoV-2 genome. The continuous updating of sequencing methods has improved our grasp of the mysteries of the viral genome. At present, the routine nucleic acid test of the new coronavirus alone cannot be used for differential diagnosis of new coronavirus variants. From the perspective of scientific research and medical diagnosis, virus mutations put forward more requirements for detection methods. By adopting the method of combining genome sequencing technology and amplification technology, firstly, based on the follow-up study of PCR screening and clinical diagnosis of positive cases, second-generation sequencing is used to determine the type and location of mutations. More extensive research on mutation sites can be accompanied by first-generation sequencing of PCR products of gene fragments of interest, which can be combined to verify and locate mutation sites faster. Through the combined use of a variety of detection methods, we will promote our further understanding of the genetic code of the virus.
4. The new coronavirus has mutated, should the vaccine continue to be vaccinated?
After the vaccine is injected, the human immune system will respond to the entire virus, including producing antibodies, and even mobilizing cellular immunity to achieve anti-viral effects. Antibodies are not only for the part of the mutation, therefore, it cannot be confirmed that the current vaccine is not effective against the new mutation B.1.1.7 of this virus. More laboratory results need to be verified, and we are positive about this.
Of course, from the perspective of the development of influenza vaccines, the emergence of virus mutations also promotes the continuous advancement of vaccine development. Viral mutations can also promote the continuous update and development of more effective and safer vaccines. As far as the current situation is concerned, we still recommend and encourage people to vaccinate to increase the risk of infection against the virus and some variants.
5. The COVID-19 virus has mutated, how to do isolation protection?
It is worth reminding the public that major scientific issues such as virus mutations and which mutations can cause disease aggravation still need more research data to answer. Therefore, it is necessary to resolutely resist the spread of mutant strains in a wider range. We still need to maintain strict physical isolation measures, such as maintaining a certain social distance, personal protection, such as wearing a mask when traveling, and paying attention to hand cleaning and disinfection.
For the significant changes that occur, the scientific research level should actively promote basic research, and medical diagnosis technology and training should be continuously improved. The prevention and control system of “early detection, early reporting, early isolation, and early treatment” is still an effective public health strategy to stop the spread.
(source:internet, reference only)