The U.S. may have more severe strains, triggering high global vigilance

Lead: The mutated virus is spreading rapidly in the United States.
How to deal with it around the world? Recently, the director of the US CDC Rochelle Walensky warned at the White House COVID-19 press conference that the increase in deaths from COVID-19 in the United States between November last year and January this year may be the result of the spread of mutated strains of COVID-19, and that the COVID-19 virus is still constantly mutating.
To infect humans.

There have been situations similar to the G614 mutant strain that made many people worry about increased infectivity.

Overview of the U.
S.
epidemic situation, as of March 7, data source: The New York Times According to statistics, although the number of newly diagnosed new coronary pneumonia in the United States in a single day has dropped significantly, many states including California and New York have seen new crowns.
Variant strains of the virus have made the situation of US epidemic prevention and control more complicated.

Currently, the number of cases in the United States exceeds 29 million, and the death toll is at least 520,000.

There are mainly two new variants of the new coronavirus that are of most concern in the United States.

One is a team of Professor Zhang Wenjuan from the Department of Molecular Pathology at Cedars-Sinai Medical Center in the United States and published a study in JAMA on February 11, stating that a new variant virus strain was discovered in Southern California, the United States.
It is called the CAL.
20C variant, also known as B.
1.
429.
This variant consists of five different mutations, of which three (S13I, W152C, L452R) are in the S protein of the virus, of which L452R is considered the most worrying .

According to the analysis and characterization of the infectivity and antigenicity of SARS-CoV-2 mutants published in the journal Signal transduction and targeted therapy, a subsidiary of Nature, L452R is a mutation that reduces the sensitivity to neutralizing antibodies by at least 4 Times.

[Based on comparative reference WUHAN-1 (GenBank: MN908947)].

Wang, Lin et al.
“Profiling and characterization of SARS-CoV-2 mutants' infectivity and antigenicity.
” Signal transduction and targeted therapy vol.
5,1 185.
3 Sep.
2020, doi:10.
1038/s41392-020-00302- 8Metz Medical recently interviewed Professor Zhang Wenjuan, the first author of the article about the discovery of a variant of the new coronavirus CAL.
20C in California.

Professor Zhang said that the CAL.
20C variant was accidentally discovered by sequencing samples at the end of last year.
At that time, at the peak of the new crown epidemic in California, a large number of cases broke out.
The Los Angeles Regional Hospital sequenced some samples to determine whether it was related to the British variant strain.

Zhang, Wenjuan et al.
"Emergence of a Novel SARS-CoV-2 Variant in Southern California.
" JAMA, e211612.
11 Feb.
2021, doi:10.
1001/jama.
2021.
1612 wrote that CAL.
20C was in Southern California in July It was first found in 1247 samples of patients with new coronary pneumonia in the California area, but it was not found again in the area until October.

Although CAL.
20C was only found in southern California in October, by November, 30 cases were found in samples from northern California, and the variant was also reported in five other states.

Professor Zhang said that until November last year, in the genetic sequencing of positive samples, the proportion of the mutant strain reached 16%, and by the end of February this year, the proportion of the mutant strain had accounted for a staggering 48%.
It has been found in at least 40 states and 20 countries.

CAL.
20C (B.
1.
429) has become one of several other widely spread variants, namely the United Kingdom (B.
1.
1.
7), South Africa (B.
1.
351) and Brazil (P1/B11248). Distribution of major global variants, https://cov-lineages.
org/global_report.
html When asked by Metz Medicine whether the new variant strains appearing in California are more transmissible and more severe clinically, Cedarsine Medical Professor Zhang Wenjuan of the center pointed out that relevant experiments and data are currently being collected.
At present, there are not enough research results to point out that new mutant strains can cause more severe symptoms or spread more efficiently.

https:// of COVID-19 Infections in San Francisco in Early March 2020 with Travel to New York and Europe, doi: https://doi.
org/10.
1101/2020.
04.
04.
20053629 Recently, "Science" reported that UCSF had early non-peer-reviewed research reports indicating that mutant strains may be more infectious , It is more likely to cause severe symptoms, and it can resist some neutralizing antibodies.
Patients infected by it are at higher risk of developing severe illness and even death.

But it needs to be pointed out that these data are still preliminary.

More data needs to be collected for further research.

The effective control of the global new crown epidemic depends on the further in-depth study of the SARS-CoV-2 virus by scientists from all over the world.

Future work needs to increase the overall large sample data volume, and will continue to conduct further monitoring and research in conjunction with the California region and the federal disease control and medical institutions.

And we should focus on virus variants in the United Kingdom, South Africa, and Brazil.
Repeated mutations at the same site in these independent variants (such as the E484K mutation site) may really have increased infectivity and risk of re-infection. On the other hand, to strengthen monitoring of the impact on existing vaccines, it is necessary to continue to conduct research on the impact of virus mutations on the effect of vaccination and the durability of vaccine protection.

Image source: National Institute of Allergy and Infectious Diseases Rocky Mountain Laboratories Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, also published a review article in JAMA at the same time, pointing out that the Cedarsene Medical Center was specifically mentioned.
The study of this new variant virus strain expressed the above concerns, but pointed out that the current degree of impact on the vaccine is unknown, and the current vaccine is still effective.

Wu Guizhen, chief biosafety expert of the China Centers for Disease Control and Prevention, also said in previous interviews that preliminary data showed that the domestically produced inactivated COVID-19 vaccine is still effective against the new variants in South Africa.

Dimas Covas, head of the Butantan Institute in the State of Sao Paulo, Brazil, also pointed out in mid-February that after testing, it was found that China's Coxing Covid-19 vaccine is effective against mutated new coronaviruses from the United Kingdom and South Africa.

However, the monoclonal antibodies produced by Eli Lilly and the monoclonal antibodies in the cocktail produced by Regeneron have nothing to do with the variants discovered in South Africa.

The other variant strain of the new coronavirus that spread rapidly in New York was named B.
1.
526.
It first appeared in samples collected from New York City in November last year.
By mid-February, it accounted for the virus sequences that appeared in the database shared by scientists.
About one-quarter of it.

The consistent results of two studies published by the California Institute of Technology and Columbia University indicate that the spread of this variant is real.

E484K mutation situation, A Novel SARS-CoV-2 Variant of Concern, B.
1.
526, Identified in New York, medRxiv preprint doi: https://doi.
org/10.
1101/2021.
02.
23.
21252259, the researchers said, this kind of rapid in New York The transmitted mutant strains are "similar" to the mutant strains found in South Africa and Brazil, including the unique mutant new coronavirus discovered in a new study by the Oregon Health and Science University.
All have E484K mutations on the S protein.
This mutation causes the virus to have a certain degree of resistance to the vaccine.
This immune escape may be able to escape the body's natural immune response and may affect the effectiveness of the existing new crown vaccine.

The E484K mutation has independently appeared in many different parts of the world, which shows that it plays an important role in the spread of the virus.

Stacia Wyman, a computer genomics expert at the University of California, emphasized: As B.
1.
1.
7 develops and gradually becomes the mainstream strain in the United States, it may accumulate more mutations.

Wyman also hinted that "other mutations may also weaken the effect of the E484K mutation.
" The combination of the'E484K' mutation of B.
1.
1.
7 has attracted greater global attention because this mutation also occurs in Maharashtra, India.
Parts of Labang.

In February, the rapid increase in the number of new crown positives such as Amravathi, Yavatmal and its surrounding areas in India found that this variant variant is related.

At the same time, Yale University immunologist Akiko Iwasaki also suggested: "I think we need to monitor mutations closely and pay attention to things that may dominate in certain parts of the world.

" Nowadays, mutations have become the root cause of the global increase in new crown cases.
Scientists are looking for ways to reduce the impact of viruses on human immunity by using mutual mutations.

The emergence of the global mutated new crown virus poses a huge threat to the global community.

On March 8th, Chinese Minister of Science and Technology Wang Zhigang said in Beijing on the issue of scientific and technological anti-epidemic that the scientific research team will do a good job on virus mutations, etc.
, and can have more precise methods for testing reagents, vaccines, and therapeutic drugs as soon as possible response.

The most effective way to prevent the emergence of new virus mutations is to reduce global cases of new coronavirus infections.
As long as the virus is still spreading, virus mutations will continue to occur.

From this point of view, in addition to strengthening the surveillance of mutant strains, support for accelerating the distribution of vaccines and strengthening public health prevention measures is the only way to end the pandemic.

Acknowledgements: The writing process of this article was supported by Dr.
Kong Yawei, Managing Director and International Medical Director of Cedars-Sinai International, and Professor Zhang Wenjuan, Department of Molecular Pathology, Cedars-Sinai Medical Center.

Wenjuan Zhang, Ph.
D.
in Bioinformatics, University of Georgia, is currently Assistant Professor and Director of Bioinformatics in the Department of Molecular Pathology of Cedarsene.

Mainly research the molecular mechanism of genetic diseases and tumors.

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