SARS-CoV-2 variants of concern (VOC) that deserve attention

Writer : Yan Jiaxin / http://blog.sciencenet.cn/blog-347754-1269710.html / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

In the more than one year of the novel coronavirus (SARS-CoV-2) pandemic, researchers around the world have sequenced tens of thousands of epidemic strains of the novel coronavirus. In recent months, some variants of SARS-CoV-2 have been detected. Because genome mutations may affect the transmission capacity of the virus, the sensitivity to vaccines, and the pathogenicity to humans, these strains are called variants of concern (VOC). In the context of the global pandemic of the new coronavirus, these variants have attracted great attention from countries around the world. Nowadays, the mutant strain that deserves attention has become one of the most popular phrases, and even the English abbreviation VOC of this phrase has become popular. This article will use the English abbreviation VOC.

What this article is going to discuss is what noteworthy changes have taken place in the new coronavirus VOC?

Darwin's theory of evolution tells us that genes that do not have an evolutionary advantage in nature will be eliminated, and species that do not have an evolutionary advantage will be eliminated. Generally speaking, in the process of evolution and mutation, the virus will develop towards lower toxicity and stronger infectivity. Low toxicity and strong infectivity are beneficial to the virus itself: it is beneficial for the virus to live in the host for a long time, multiply, and "infect" more hosts, so that the virus has more chances of survival.

This is a long-term inevitable trend, but in a short period of time or in certain local areas, this trend may not necessarily become a reality immediately. Therefore, the specific situation needs specific analysis.

In terms of the evolutionary trend of the novel coronavirus that is currently in a global pandemic, the current VOC of the novel coronavirus is not surprisingly large in terms of its transmission ability, sensitivity to vaccines, and pathogenicity to humans. The evidence for certain tendentious conclusions widely circulated in the current media is insufficient, and it is still awaiting the development of the epidemic and further and in-depth research to finally obtain a clear conclusion.

1. VOC transmission ability

The SARS-CoV-2 variant called B.1.1.7 appeared in the United Kingdom in September 2020. The VOC has 17 genome mutations, some of which lead to changes in the amino acid of the spike protein (see above) Figure). Similar but very different variants (B.1.135) have also been found in other places such as South Africa and Brazil, but the study of the B.1.1.7 lineage of the United Kingdom is more in-depth. A good summary of these variations can be found in Reference 1.

A series of evidence indicates that compared with previous isolates, viruses of the B.1.1.7 lineage may have a higher transmission capacity. These include the rapid replacement of the previous variants in the UK in a short period of time; the R index (the average number of people infected by an infected person) of such variants has increased significantly; the level of viral RNA in the nasopharyngeal cleansing fluid detected by PCR or RNA sequencing has increased .

The virological definition of virus transmission is the transfer of viruses from one host to another. In the case of SARS-CoV-2, this transmission occurs when infectious virus particles are exhaled through respiratory droplets and reach another host, where they begin to infect. The evidence of increased transmission of B.1.1.7 pedigree cited above is all indirect, and cannot prove that mutant strains are actually more likely to spread between hosts in a virological sense. For example, the increase in the spread of this mutant strain in the population may also be the result of changes in human behavior. The R index, which measures transmission capacity, is not only affected by viruses, but also by human behavior. The increase in RNA levels found in nasopharyngeal lotions is not decisive for transmission. Because viral RNA is different from infectious virus. The relative amount of infectious virus excreted by individuals infected with the B.1.1.7 variant and infected with other variants has not been studied.

There is no doubt that the B.1.1.7 lineage quickly replaced other lineages in the UK. However, whether this phenomenon is due to the increased ability of the virus to spread from one host to another has not yet been confirmed.

The mutant strain has also been found in other countries, and its spread in these areas is not consistent with the increase in transmission. For example, we now know that the B.1.1.7 lineage appeared in the United States 5-6 weeks before it was discovered in the United Kingdom, but as of January, it only accounted for 0.3% of all cases in the United States. Two months after the epidemic in California, this lineage is estimated to account for 0.4% of cases, compared to 1.2% in similar cases in the UK. In Florida, this lineage is associated with higher transmission capacity, accounting for 0.7% of cases, but this is not the case in other US states. These data emphasize that we cannot yet conclude that the B.1.1.7 lineage is biologically more infectious.

There may be multiple factors at play, which is why it is best to look at B.1.1.7 pedigree variants and other variants from the perspective of virus fitness and reproduction success. Many factors can affect adaptability, not just communication capabilities. These may include increased physical stability of virus particles, increased resistance to immune responses, prolonged existence of the virus in the nasopharynx, increased infectious virus production in the host, and higher efficiency in the establishment of infection in the host. Any slight increase in these abilities may form a specific variant strain in the population, but it will not actually affect its spread from person to person. Whether the spread of these mutants is only achieved through founder effects at the right time and at the right place must also be considered.

The statistical model used to simulate the spread of SARS-CoV-2 variants cannot prove that its biological characteristics have changed, because the prevalence in the population may be a comprehensive result of multiple fitness parameters. It is necessary to conduct experiments in animal models (in this case, the relevance to humans is unclear), or quantitative detection of infectious viruses in the population. So far, there has not been such a quantitative test in the population for the current variant strain.

2. The sensitivity of VOC to vaccines

A more pressing question is whether changes in the spike protein in VOCs will affect the immune protection of existing vaccines, or whether it will affect the sensitivity of VOCs to existing vaccines. To clarify this issue requires direct testing of neutralizing antibodies, such as those that can prevent the protection of infection. Antibodies recognize specific protein sequences on viral particles, especially those spike protein sequences used in mRNA vaccines. Some of the spur changes found in mutant strains are in areas known to bind antibodies. Therefore, an important question is whether vaccination can suppress VOC infection.

This problem has been solved in Moderna and Pfizer mRNA vaccines. The serum produced after inoculation with mRNA-1273 can effectively neutralize the experimental pseudovirus carrying the SARS-CoV-2 spike glycoprotein of the B.1.1.7 lineage (see Reference 1). When using the South African B.1.351 lineage, the neutralizing potency of these sera was reduced by 6.4 times. However, these serums can still completely neutralize South African B.1.351 at a titer of 1:290, which may be sufficient to prevent severe new coronary pneumonia (COVID-19).

At the same time, Moderna has announced that it will develop an improved vaccine (mRNA-1273.351) that encodes an amino acid that changes in South Africa B.1.351.

In another study (Reference 2), a neutralization test was performed on the serum of individuals vaccinated with Pfizer's BNT162b2 mRNA vaccine, using B.1.1.7 (absent amino acids 69/70, N501Y, D614G) or B.1.351 (E484K) + N501Y + D614G) SARS-CoV-2 virus with amino acid changes in the selective spike protein. It was found that these changes in VOC have little effect on serum neutralization.

However, these modified viruses do not contain all the changes found in the B.1.1.7 and South African B.1.351 viruses, which may explain the different results of serum tests compared to the antibodies induced by mRNA-1273.

These observations convince us that these two mRNA vaccines will provide protection against COVID-19 caused by the currently circulating variant strains. Of course, the mutation of the virus also has great chance. The monitoring of the virus genome must be increased to ensure that any new mutations that may appear are quickly detected and to determine its impact on the neutralization of existing vaccines.

3. The pathogenicity of VOC to humans

There is no evidence from previous studies that viruses of the B.1.1.7 lineage are associated with an increased risk of hospitalization or death. However, after reviewing additional data from three independent studies, NERVTAG (New & Emerging Respiratory Threats Advisory Group, Reference 3) concluded that infection with VOC B.1.1.7 is associated with an increased risk of death compared with non-VOC infections Related, this is a realistic possibility. This conclusion is based on a statistical analysis of reported mortality of individuals infected with VOC B.1.1.7 or non-VOC viruses. For example, in one study, the relative risk of death was 1.35 (95% confidence interval 1.08-1.68). In another study, the average rate of case mortality caused by VOC viruses or non-VOC viruses was 1.36 (95% confidence interval 1.18-1.56). These differences are actually very small, but there is a large confidence interval, from no impact to impact. The author points out that the absolute risk of death remains low. Statistics are calculated by analyzing a limited data set of all COVID-19-related deaths (8%), so there may be errors. In addition, there does not appear to be an increased hospitalization risk associated with VOC virus infection.

Our interpretation of this report should be that it is mainly used as a warning to continue genomic monitoring related to the risk of death on the mutation of the virus, rather than immediately drawing a causal conclusion.

Latest news: Novavax has just released the first batch of results of a Phase III clinical trial of a COVID-19 vaccine based on spur protein (Reference 4). The efficacy in the UK is close to 90%, but in a small trial in South Africa, the efficacy on the B.1.135 variant strain was only 50%.

References:

1.　Kai Wu, et al., mRNA-1273 vaccine induces neutralizing antibodies against spike mutants from global SARS-CoV-2 variants, bioRxiv, Posted January 25, 2021. doi: https://doi.org/10.1101/2021.01.25.427948

2.　Xuping Xie, et al., Neutralization of SARS-CoV-2 spike 69/70 deletion, E484K, and N501Y variants by BNT162b2 vaccine-elicited sera, bioRxiv, Posted January 27, 2021. doi: https://doi.org/10.1101/2021.01.27.427998　

3.　Peter Horby,et al, NERVTAG note on B.1.1.7 severity, Jan 26, 2021, https://app.box.com/s/3lkcbxepqixkg4mv640dpvvg978ixjtf/file/768458300892

4. 　 Katie Thomas, et al, Novavax's Vaccine Works Well — Except on Variant First Found in South Africa, New York Times, Jan. 28, 2021, https://www.nytimes.com/2021/01/28/health/covid-vaccine-novavax-south-africa.html

UPDATES 01/02/2021

News (1)

British media: Research confirms that SARS-CoV-2 originated in China

Reporter : Yuning / Editor : Ling Yuge / https://www.soundofhope.org/post/469481 / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

During the long-overdue investigation of the source of SARS-CoV-2 (CCP virus) by the World Health Organization in China, British reporter Ian Birrel  on  January 30 quoted  an article in the Daily Mail, revealing that the results of a team specializing in molecular epidemiology at the Institute for Genomics and Evolutionary Medicine at Temple University in Philadelphia confirmed that the CCP virus originated in mainland China and may have appeared from the end of October to the beginning of November 2019.

The team led by Professor Pond (Sergei Pond) published a paper on the BiroRxiv website in September last year. As early as when people confirmed COVID-19 (covid, in short), experts realized that the disease was derived from the virus SARS-CoV-2. So the team used modeling technology to track the evolution of SARS-CoV-2 to covid to understand the invisible mutation process and development process of this virus.

Their research results found that the early CCP virus lineages first appeared in the samples of the genome sampled from China. In fact, the next five main lineages were also the first to be found in China, which means that these variant strains are all sources that came from China and evolved from the virus in China.

Pound said, "All genetic evidence shows that this virus originated in mainland China, and the pattern of this virus's global spread is consistent with the pattern of global outbreaks of infectious diseases from mainland China."

Pound also said that it is very difficult to confirm the exact date of the appearance of patient zero, but he believes that the progenitor cells of the CCP virus may have appeared at the end of October 2019. Several researchers were infected with the epidemic at the same time.

The CCP only admitted to the outbreak of "a new infectious disease" in Wuhan on 31 December 2019, and only three weeks later did it admit that the virus can be transmitted from person to person, although many early signs showed that the virus can spread among medical staff and have spread among the people in Wuhan.

Wuhan medical staff stated in a report on 2 January 2020 that 41 confirmed patients had appeared in Wuhan. A report from the South China Morning Post confirmed that Wuhan had the first confirmed covid case on 17 November 2019. The WHO now admits that at the end of 2019 they knew that there were 124 confirmed cases in mainland China and only 5 of them were not from Wuhan. Many experts and government officials complained that WHO had concealed this important information.

People are now paying attention to the Wuhan Institute of Virology because Shi Zhengli's team is conducting artificial virus recombination experiments there.

News (2)

WHO experts investigate in Wuhan, CCP strictly controls the whole process

Reporter : Ruyi / Editor : Song Feng / https://www.ntdtv.com/gb/2021/01/31/a103044042.html / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

Experts from the WHO Virus Source Investigation Team began their investigation in Wuhan after the two-week quarantine period ended. Under strict control, they were arranged to visit the hospital where the CCP virus patients were first admitted, and they were also arranged to visit the "Wuhan Anti-epidemic Achievement Exhibition." The outside world believes that the WHO expert survey conducted in accordance with the arrangements of the CCP is more like filming.

On January 29 and 30, the WHO Virus Origin Investigation Team visited Hubei Province Integrated Traditional Chinese and Western Medicine Hospital and Jinyintan Hospital in Jianghan District, Wuhan.

According to the Voice of America ​​report, WHO experts are not allowed to contact the media or talk to community residents at will.

The report quoted sources saying that all people who talk to the members of the expert group are designated by the superiors. What can be said, what cannot be said, and how to say must be in accordance with the requirements of the superior.

China also arranged for the WHO investigation team to visit the "Wuhan Anti-epidemic Achievements Exhibition" aimed at highlighting the leadership role of the Communist Party of China.

Gobi Dong, an independent scholar in the United States, said that in the early stages of the outbreak, WHO did not investigate the source of the virus; when the virus was the most serious threat to the world, WHO did not go to China to investigate. Last year, many countries participated in the WHO meeting. It was proposed to trace the source of the virus but the WHO still did not act. But a year later, they went to China to investigate the source of the virus, which is counterintuitive.

Gobi Dong added, "The whole world knows that this is just a play by the CCP and its infiltrated WHO. First, it has been a year since all the viruses The evidence is almost destroyed. It’s impossible for an evil regime like the CCP to leave you with any evidence after a year. Second, an evil regime like the CCP’s centralized power needs to investigate it. The guilt is simply seeking skin with a tiger."

The WHO notified on its Twitter account on the 28th that the expert team is going to visit several hospitals in Wuhan and the South China Seafood Market related to the first batch of patients. It will also visit Wuhan Institute of Virology, Wuhan CDC and several subordinate laboratories.

In fact, the trip to China of the WHO expert group has been delayed many times by China. French media pointed out that the investigation mission has been highly politicized. Beijing has been trying to divert attention from the outside world by dismissing statements such as "the epidemic may also originate from abroad," and avoiding the outside world from paying attention to its slow response at the beginning of the epidemic.

Voice of America ​​also stated that the Chinese Communist Party officials have been dumping other countries in order to avoid accountability.

Ms. Yu from Wuhan said that a visit was arranged in a tightly controlled area, and all things you saw were made, just like people going to North Korea.

Ms. Yu commented, "You want people from that area to get things from them. What can you do in the controlled area? What can you get? Does it make sense to get the things that the government provides to you? It's nonsense, right? It's all funny, to coax the people."

Ms. Yu said that citizen journalist Zhang Zhan just took some photos on the street, said a few words to some people, and made a video and she was sentenced to four years. Ai Fen, the doctor who told the truth, was falsified and then deliberately blinded her eyes during the operation. Who dares to tell the truth?

Ms. Yu also said that if we really want to investigate, we should investigate how the infected people died and how many people died. At that time, the Wuhan crematorium was burning continuously for 24 hours, and foreign support was needed. It makes sense to investigate these.

Ms. Yu said, "They should look at the people who died, how they died, the process of their death, the whole process of their illness and death, they have to understand this, and then their families. What are so many orphans like now? Why don’t these things look, care, or ask?"

The Ministry of Foreign Affairs of the Communist Party of China stated that the WHO experts' visit to Wuhan this time is a cooperation and a part of global research rather than investigation.

Gobi Dong pointed out that after this year, the whole world has fully seen this institution known as the World Health Organization through this epidemic. In fact, it has long been infiltrated by the CCP. Its two secretary-generals are the products of the CCP's money diplomacy. This is also one of the reasons for the catastrophe of this century.

Gobi Dong commented, "The infiltration of a world organization like WHO by the CCP is actually the greatest tragedy in the world, and it is also the greatest danger in the world. This time the Wuhan virus of the CCP is occupying the world, and WHO has played an indispensable role. Without it, it helps the CCP. With the cover-ups and lies, the world will not suffer such a pandemic as it is today. Therefore, the CCP and the WHO organization are among the killers of the virus."

Gobi Dong asked, " What can be the result of asking one murderer to investigate another murderer?" Therefore, the WHO's visit to China to check the source of the virus can only be a scene, and it must be returned without success, and it may even become a farce for the CCP to spread fat and invite awards.

News (3)

What are the effects of SARS-CoV-2 on children?

 

Publisher : Xinhua News Agency / http://news.sciencenet.cn/htmlnews/2021/1/452642.shtm / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

How are the symptoms of children infected with SARS-CoV-2 (novel coronavirus, CCP virus) different from those of adults? What impact will the mutant novel coronavirus have on children? How should people take measures to protect the safety of children? Experts from the World Health Organization recently answered the above questions in the form of a podcast.

Maria Van Kelkhoff, head of WHO's new crown virus technology, said that people of different ages behave differently after being infected with the new crown virus. Most people will experience respiratory symptoms such as fever, cough, sore throat, and sneezing after being infected with the CCP virus. Some people will also experience smell and taste failure and gastrointestinal symptoms. But compared with adults, children and adolescents tend to have milder symptoms. For example, young children usually do not have as many symptoms as adults, some children may have gastrointestinal symptoms such as mild diarrhea or vomiting, and most children do not even have any symptoms.

Regarding the discovery of mutated novel coronaviruses in many places around the world, Van Kelkhoff said that the mutation of the virus is expected. Many mutations have no effect on the transmission capacity of the virus and the severity of the disease caused, but some "virus variants that need attention" It is worth further study. She also believes that so far these mutant novel coronaviruses have not been shown to cause more serious diseases in people of all ages. Studies have shown that the mutant virus found in the UK has shown greater transmission capacity among people of all ages, but children are not more susceptible to this mutant virus than adults.

Van Kelkhoff said that in the face of the CCP virus epidemic, the best way to protect children is to prevent infection. The protective measures that people often hear also apply to children. Specifically, to ensure that children maintain hand hygiene, learn to wash their hands properly with soap and water, you can wash your hands while singing to ensure that enough foam is made to wash your hands, you can also use alcohol-based hand washing gel. Ensure that children pay attention to hygienic etiquette, such as coughing and sneezing inside the curved elbow, which are also good habits that children should develop as they grow up. Ensure that children follow the instructions of the local health department and wear masks suitable for their age. Use clean hands to properly wear a mask and cover your mouth and nose, and wash your hands after removing the mask; keeping social distance with others is a good way to prevent the spread of the CCP virus.

Van Kelkhoff finally stated that parents should also answer their children's questions as much as possible. Many confusing information may make children panic. So take time to talk with children and alleviate fear by correctly answering their questions.

News (4)

People who "take pictures" of  SARS-CoV-2

 

Reporter : Peng Qian / http://news.sciencenet.cn/htmlnews/2021/1/452306.shtm / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

Li Sai, a researcher at the School of Life Sciences, Tsinghua University, China, was extremely excited when he watched the nano-level fine microbe structure of the fresh SARS-CoV-2 (novel coronavirus, CCP virus). He told reporters on the 23rd, "It feels like climbing Mount Everest and overlooking the world."

For the first time, an international team including Chinese researchers "shooted" a 3D image of the novel coronavirus. In the nano-scale image, the new coronavirus with an average diameter of less than 100 nanometers is like a strange planet, with freely swinging spike protein "tentacles" distributed on the surface. Inside the "planet", ultra-long ribonucleic acid strands are densely wound around the ordered ribonucleoprotein complexes.

Recently, a high-definition science image of the new crown virus, co-operated by the Lisay Laboratory of Tsinghua University, the Austrian Nanomapping Company, and the team of King Abdullah University of Science and Technology Ivan Viola in Saudi Arabia, came out.

"CT examination" reveals the truth

Li Sai still clearly remembers the moment when he analyzed the structure of the new coronavirus. At 9 o'clock in the evening at the beginning of June last year, the computer screen showed the complete structure of the virus: the huge spike protein grows awkwardly on the capsule, and the capsule is wrapped in many small protein balls.

He was very excited and dialed the laboratory phone with a trembling hand: "Notify everyone, stop all work, come to my office, the whole structure of the new crown virus has been solved. We may be the first in the world to see it so real and clearly. Its team!"

This is the team's more than 100 day and night research results. They successfully analyzed the three-dimensional structure of the CCP virus using cryo-electron microscope tomography and sub-tomographic average reconstruction technology.

This result is also inseparable from the cooperation with the research team of Academician Li Lanjuan, the State Key Laboratory of Infectious Diseases Diagnosis and Treatment of the First Affiliated Hospital of Zhejiang University School of Medicine. The results of the cooperative research were published in the online edition of the American journal Cell on September 15 last year. . This is the scientific basis of the latest 3D virus popular science images.

Soon after the outbreak, Li Sai contacted Academician Li Lanjuan, who was on the front line of the fight against the epidemic, and obtained the inactivation of the new coronavirus to power the microscope. The CCP virus that has been inactivated by paraformaldehyde still retains its original appearance.

In the laboratory of Tsinghua University, the inactivated new crown virus was placed under a cryo-electron microscope, and a photo was taken every 3 degrees of rotation, a total of 41 photos were taken, and then three-dimensional reconstruction was carried out, just like a "whole body CT examination" for the virus.

After days of intensive work, the team member, 23-year-old graduate student Song Yutong, saw the dense virus under the cryo-electron microscope for the first time, and was scared to cry. There was such a high concentration of the virus in a small drop of liquid that made her "sweat coldly."

The team also used a cryo-electron microscope to "flash a flashlight" into the virus, passing through the envelope, clearly illuminating the arrangement of ribonucleoprotein complexes inside the virus, showing the most complete image of the new coronavirus so far. The cryo-electron microscope uses electrons as the "light source" to penetrate the virus sample to obtain information on the surface and internal structure of the virus.

The analysis of the structure of the CCP virus has also made the development of vaccines and neutralizing antibodies more "targeted." For example, the team observed that the spike protein on the surface of the novel coronavirus is randomly distributed, in a variety of states, and relatively fragile and easy to fall off. Such complex antigen distribution makes it necessary to consider the specific distribution and structure of the spike protein on the surface of the virus when developing vaccines and neutralizing antibodies.

The team also uploaded the high-definition three-dimensional structure of the new crown virus to the electron microscope database for free download worldwide to facilitate subsequent scientific research and popular science.

Sino-foreign cooperation construction

After the Li Sai team shared the structure, cooperation and interview invitations came one after another. In August last year, a letter from King Abdullah University of Science and Technology aroused great interest from the Li Sai team.

This is a computer vision team focused on microscopic biological imaging. Team leader Viola hopes to jointly develop a more scientific and true science image of the CCP virus. This is exactly the original intention of the Li Sai team to analyze the virus structure.

"People always take things lightly to what they can't see. I think only by presenting the virus to the world as soon as possible in a true, complete, and clear manner, and letting everyone see its terrifying image, will more people take it seriously." Li Sai Say.

Li Sai told reporters on the 23rd that some institutions have released some hypothetical models of the new coronavirus, but there are a lot of errors, such as the distribution of the spike protein and the overall proportion of the virus. The team hopes that every detail of the image of the virus respects the cutting-edge scientific discoveries of the virus.

A hard drive containing 2TB of research data and images was sent from Beijing to faraway Saudi Arabia. Based on the three-dimensional structure of the whole virus analyzed by the Li Sai team, the Viola team used the advantages of artificial intelligence image processing and programming to construct a fine 3D image of the virus, which was made into a video by the Austrian Nanomapping Company.

The CCP virus mainly infects the human body through the binding of the surface spike protein to the human angiotensin converting enzyme 2 (ACE2) receptor. The spike protein is like a "key", and the ACE2 receptor is like a "lock". When the key opens the lock, the virus can enter the cell.

The latest video restores the process of the CCP virus invading human cells: at the moment of invasion, the new coronavirus binds to the receptor and fuses with the cell membrane. The video also shows the angle between the spike protein and the tangent perpendicular to the novel coronavirus membrane, as well as the angle range of the spike protein swinging on the surface of the virus membrane.

According to Li Sai's team, the study found that the spike protein is flexible, and its swing feature will make the new coronavirus more flexible when it attacks cells, which is conducive to the binding of the spike protein to the ACE2 receptor on the cell.

In the video, the spike protein on the surface of the virus slightly swings like a chain hammer. These true restorations of the details of the live virus come from the close collaboration of the Chinese and foreign teams for nearly half a year.

In Li Sai's view, this is the epitome of new crown international scientific research cooperation. The epidemic has allowed scientists around the world to unite and share scientific research results for the first time to help vaccine, antibody research and development, and epidemic prevention and control. This spirit of mutual assistance and cooperation and its results have inspired everyone.

News (5)

Sharing information about SARS-CoV-2 with the international community, China did so at the time

 

Reporter : Dong Ruifeng / http://news.sciencenet.cn/htmlnews/2021/1/452305.shtm / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

Searching for pathogens, isolating viruses, sharing in time... Chinese scientists race against time to quickly identify the pathogen and actively share the gene sequence of the CCP virus with the international community for the world’s epidemic prevention and control such as diagnostic reagent design, drug screening, vaccine development, and virus traceability Work to earn valuable time.

The first batch of laboratory biosafety experts who faced the new crown pneumonia epidemic were interviewed a few days ago to review this battle with the CCP virus.

"If we don't know the situation of the virus, it's like we can't find an enemy on the battlefield." said Wu Guizhen, the chief biosecurity expert of the Chinese Center for Disease Control and Prevention. On January 2, 2020, upon receipt of case specimens submitted for inspection by Hubei Province, Wu Guizhen, the team of Tan Wenjie and Zhao Xiang of the Institute of Viral Diseases of the China Centers for Disease Control and Prevention immediately entered a "relay race" to decipher the genetic code of the virus.

According to expert research and judgment, the National Health Commission organized the China CDC, Chinese Academy of Medical Sciences, Wuhan Institute of Virology, Chinese Academy of Sciences and many other institutions with high-level biosafety laboratory conditions to carry out pathogen identification in parallel.

In order to understand the full picture of the virus in the fastest and most accurate way, the China Centers for Disease Control and Prevention's Institute of Viral Diseases has coordinated the layout, with the emergency technology center as the core, combined with the Biosafety Level 3 Laboratory of the Institute of Viral Diseases, the National Influenza Center, and the Central Instrument Room Jointly tackle key problems, and simultaneously adopt first-generation, second-generation and third-generation sequencing technologies to fully carry out whole-genome sequencing.

Also on January 2, 2020, the Chinese Academy of Medical Sciences received the first batch of case specimens submitted for inspection by Hubei Province, and immediately began sample analysis and other work. The analysis found that the same unknown coronavirus sequence was found in the microbiome sequences obtained from the samples, and the coronavirus sequence was the main virus sequence, and no other clear pathogenic information related to acute respiratory infections was found.

Zhou Peng, a researcher at the Wuhan Institute of Virology, Chinese Academy of Sciences, introduced that Wuhan Institute of Virology, as a professional virus research institution with high-level biosafety laboratories, immediately organized scientific researchers to invest in scientific research after receiving samples of pneumonia cases of unknown cause sent by special personnel from Wuhan Jinyintan Hospital. The work mainly involved the establishment of virus genome sequencing, virus isolation and virus-specific detection methods.

Genome sequencing conducted by several laboratories in parallel found that the same new type of coronavirus genome sequence was present in the samples submitted for inspection, and this genome sequence did not exist in healthy people and other types of pneumonia patients. The identification of the pathogen has taken a critical step.

While sequencing the genome, scientists are racing against time to carry out virus isolation work. Virus isolation is the gold standard for pathogen diagnosis and one of the most critical evidences for epidemic research and judgment. Considering the complexity of virus isolation, in order to improve the success rate of virus isolation, they adopted multiple virus isolation strategies at the same time. On January 7, 2020, the Chinese Center for Disease Control and Prevention “captured” the culprit of the epidemic for the first time under an electron microscope—a new type of coronavirus with a typical corona shape and crown-like outer particles.

After comprehensively considering the genome sequence determination, the successful isolation of the virus, the acquisition of virus electron microscopy photos, pathogenic testing and clinical diagnosis and other evidence, on January 8, 2020, the National Health Commission's expert evaluation team initially confirmed that the novel coronavirus is the pathogen of the epidemic. On January 9, the expert evaluation team of the National Health Commission released information on the pathogen of viral pneumonia of unknown cause in Wuhan. The pathogen was initially judged to be a new type of coronavirus. China notified the World Health Organization of the epidemic information and shared the initial progress made in pathogenic identification with the World Health Organization.

"The initial identification of the virus in such a short period of time is a remarkable achievement." The WHO website evaluated that day.

Based on further comparison and verification of multiple samples, on January 12, 2020, the Chinese Center for Disease Control, Chinese Academy of Medical Sciences, and Wuhan Institute of Virology of the Chinese Academy of Sciences, as designated agencies by the National Health Commission, submitted the novel coronavirus genome sequence information to the WHO. Published in the global influenza sharing database, shared globally. The National Health Commission and WHO shared the genome sequence information of the novel coronavirus.

This means that the whole world can share this source information to develop testing reagents, vaccines, etc., to "confront" the virus head-on. In this time-running encounter, Chinese scientists have not been afraid of hardships and dangers, have selflessly dedicated, and used scientific rigorous attitude and professionalism to provide key information for global epidemic prevention and control and inspiration.