Kexing: the necessity of developing mutant vaccine will be evaluated as soon as possible

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aimed at the latest COVID-19 mutation, the reporter learned from the new crown vaccine production company Kexing company, Kexing highly concerned about COVID-19 Omicron mutation information, has launched through the global partner network to actively collect and obtain information and samples of new variants. The evaluation and research will be carried out as soon as possible to understand the impact of Omicron strain on the existing COVID-19 inactivated vaccine and the necessity of developing variant vaccine. p> Kexing said that the company has mature vaccine production technology and large-scale production capacity. Previously, it has carried out the development of new crown inactivated vaccines for gamma strain and delta strain. If necessary, the company can quickly promote the development and large-scale production of new vaccines, and has the ability to ensure the vaccine demand related reading: [who listed the new strain as a variant that needs attention and named it Omicron] CCTV news, Xinhua News Agency CCTV news on November 27. On November 26 local time, who held an emergency meeting to discuss the new crown variant of b.1.1.529. The World Health Organization will issue a statement that it will be listed as "Variant of Concern" and named Omicron (

, according to Xinhua news agency, WHO will list the newly reported COVID-19 variant B.1.1.529 B.1.1.529 as a "mutant" strain that needs attention, and the Greek letter "Concern". Ο） Naming requires countries to strengthen monitoring and sequencing. after a special evaluation meeting on the strain, who said that the latest variant strain was first confirmed in South Africa on November 9 and first reported to who on November 24. Epidemiologically, the new crown infection rate in South Africa has increased sharply in recent weeks, which is consistent with the detection of b.1.1.529 variant strain

"This mutant strain has a large number of mutations, some of which are worrying," the who said in a statement Compared with the variant strain of b.1.1.529, the b.1.1.529 strain may increase the risk of secondary infection with the new crown, which also seems to be consistent with the increase in the number of cases infected with b.1.1.529 strain in South Africa. the who said that the b.1.1.529 variant strain was detected faster than other variant strains that caused the surge of infection in the past, indicating that this latest variant strain may have There are growth advantages. who calls on countries to strengthen the monitoring and sequencing of all new crown variant strains that are still prevalent, submit complete virus genome sequences and metadata to the public database, and report to who any "need attention" At the same time, who also recommends international collaboration to better understand the impact of variant strains that "need attention" through field investigation and laboratory evaluation. according to the definition of who, "need attention" The mutated strains refer to the strains that have been proved to have one or more of the following changes at the global public health level: increased transmissibility or harmful changes in epidemiology, increased toxicity or changes in clinical manifestations of disease, reduced effectiveness of public health and social measures or existing diagnostic methods, vaccines and treatment methods, etc. [what does it mean that the latest variant found in South Africa is listed as a "variant to be worried about?] Intern / Cao Yuan / Huo Siyi Geneva, at 11:00 noon on November 26, 2021, the World Health Organization is urgently convening a closed door meeting to discuss whether the latest variant of b.1.1.529 found in South Africa should be listed as a" variant worthy of attention " (VOI), or a more dangerous level: "variants that need to be worried" (VOC). A few hours later, the results came out. who issued a statement, listing b.1.1.529 as "variants that need to be worried" and named Omicron (named after the 15th Greek letter, Chinese translation "Omicron") This means that experts from the WHO virus evolution technology advisory group believe that the new variants have higher transmission or pathogenicity, or may reduce the effectiveness of current diagnosis, vaccines and therapies. previously, four variants were included in VOC by who, including alpha, beta, gamma and delta with the strongest transmission, and Omicron became the fifth. The who pointed out that Step evidence shows that compared with other VOCs, this variant may increase the risk of reinfection in the population. the first known infection case of Omicron variant is from the sample collected in Gauteng Province, South Africa on November 9, 2021. (picture source: PBS video screenshot) but many experts expressed their opinions on China Newsweek It is pointed out that at present, further research is needed to analyze whether the transmissibility of this variant is really greater than Delta, which depends not only on the gene mutation of the variant itself, but also on the actual transmission trend in the population. The influencing factors of the latter are not only related to the characteristics of the virus, but also related to the vaccination rate, epidemic prevention policy, population structure, etc. "There's no need to raise the alarm yet. Don't panic now," Jin Dongyan, a virologist at the University of Hong Kong, told China Newsweek Emphasis. He pointed out that to believe in science and watch its changes, the most important thing is to strengthen monitoring. The follow-up mainly focuses on the evolution of three characteristics of new varieties: transmissibility, pathogenicity and immune escape ability. What does 32 mutations mean? Omicron is considered to be the "most dangerous strain" , because 32 mutations were found in its spike protein. This number of mutations is "unprecedented", said Neil Ferguson, director of the MRC global infectious disease analysis center at Imperial College London. compared with Delta, which swept the world, there are only 16 mutations. Of all the mutations, they are located in the receptor binding region (RBD) This is the "channel" for the virus to enter human host cells Omicron has at least 10 mutations in the region, two in Delta, three in beta, and 5 times in Omicron.

, however, points out that the number of mutations does not mean that the virus's transmission capacity or immune escape is even stronger. Jin Dongyan has discovered nearly 30 thousand mutations in the whole genome sequence of COVID-19. "32 out of more than 30000, only about 1%, and the spike protein itself contains about 1200 amino acids." changing more than 30 is also a decimal. " compared with the number, the key is which sites have changed。 according to the published b.1.1.529 gene sequencing data, several of the 32 mutated loci are familiar to us. For example, n501y mutation in alpha and beta variants can improve the binding ability of spike protein to receptor ACE2, so as to enhance the infectivity of the virus. Another mutation E484 is the key site to help the mutant strain escape the current vaccine immunity. Both beta and gamma variants contain this mutation. In addition, the new variant rarely has two mutations near the cleavage site of Flynn protease at the same time, namely p681h and n679k. These two mutations may strengthen its immune escape ability and make the spike protein easier to be cleaved, so as to enhance the infection ability of the virus. One of the important reasons for the enhanced transmission of delta variant is that p681r mutation is carried near Flynn protease cleavage site it is also noteworthy that b.1.1.529 carries many new mutations that have not been found before. "This variant contains many unfamiliar mutations," said Penny Moore, a virologist at the University of Witwatersrand in South Africa her team is analyzing the replication ability and immune escape characteristics of b.1.1.529 in the laboratory. Moore previously said that because the variant contains too many mutations, the process of neutralizing it "becomes complex". The latest news released by her team is very worrying. Computer modeling suggests that b.1.1.529 can escape T cell immunity to a certain extent compared with humoral immunity, human immune response mainly depends on T cell immunity to eliminate the virus, and cell immunity also has memory immune response, which can prevent human secondary infection. Lu Mengji, a German Chinese virologist and professor of Essen University, pointed out to China Newsweek that the evaluation of the ability of a vaccine to resist the mutated virus mainly depends on its ability to induce the diversity of human immune response. The most key is the ability to induce human T-cell immune response b.1.1.529 more unknowns need to be further "opened" Lu Mengji stressed that the invasiveness of b.1.1.529 and the change of antibody neutralization ability can only be known after epidemiological investigation, experiment and other observation and research. There may be an answer in the next few weeks. Moore also pointed out that it is too early to draw a conclusion whether the infectivity of the new variant is really enhanced. Her team hopes to obtain the first more accurate result within two weeks concerns about the spread of new varieties will naturally lead to a more concerned question: will Omicron surpass Delta and become a new generation of global epidemic strains in the view of golden Dongyan, it is still unknown whether Omicron will become a new dominant plant. The variation of COVID-19 is limited. In general, many variants of the new crown have not survived. Even a few surviving variants, few of them can become the dominant strain. p> the first known case of infection with the Omicron variant came from a sample collected on November 9, 2021 in Gauteng Province, South Africa. (photo source: PBS video screenshot) "from the outbreak of the epidemic to now, at least hundreds of variants have been found, but only one delta can stay. In the past, beta and gamma variants have also been proved to have strong immune escape characteristics, but they still lost the communication competition with Delta, and finally disappeared silently." Jin Dongyan pair China Newsweek Explanation. he also said that it can be better judged only when the strain spreads to a certain scale. At present, its transmission scale is still very small, mainly limited to South Africa. the first known Omicron infection case comes from the sample collected in Gauteng Province, South Africa on November 9, 2021. Although the total number of newly confirmed cases in South Africa is relatively low, it has increased rapidly in the past seven days In addition, 273 new infections were recorded on November 16, but by November 25, the number had risen to more than 1200, of which more than 80% were from Gauteng Province. Moreover, among the 77 virus samples collected in Gauteng Province from November 12 to 20, gene sequencing showed that they were all Omicron variants. as of November 25, 2021, they had spread to three countries and regions, Gauteng, South Africa There are at least 77 cases in China, 4 in Botswana and 2 in Hongkong, China.

World Health: no travel restriction is needed.

is not yet clear where the source of this new variety is. However, some scholars speculate that it can be derived from patients with weaker immune system. Professor Francois Baloks, director of Genetics Research Institute of University College London, said that there were a large number of mutations in B.1.1.529 variant strains. Apparently, it was accumulated in a single outbreak, suggesting that it may have evolved from a weak immune system, such as untreated AIDS (HIV), during chronic infection.

"this is a conjecture." a visiting virologist told China News Weekly. However, he believes that it is still necessary to observe the local cases, such as whether the cases have basic diseases and immune defects. If there is no basic information, it can not be inferred. Jin Dongyan explained that there are "a lot of mutations" in the new varieties , there are three possibilities: one is that the virus has been transmitted for many generations in people with immune deficiency; the other is that the virus will also show "unusual" when it spreads in other animals and returns from animals to people Third, due to the relatively backward development of public health in a region, the virus may have been quietly popular in this region for a long time and many mutations have occurred, but it was not found in time due to insufficient sequencing. in fact, since the new crown pandemic, the Research on the evolution of more viruses in HIV patients after infecting the new crown has been ongoing. Researchers from the African Institute of health and KwaZulu Natal University published a paper on persistent sars-cov-2 infection and host evolution associated with advanced HIV infection on the preprint website on June 4, 2021 The object of the study was a more than 30 year old HIV positive woman who had been infected with COVID-19 for more than 6 months. During this process, the viral population changed significantly in this woman: sixth days after infection, the E484K mutation occurred in the receptor binding domain of COVID-19 in the host, and two spikes of K417T and F490S appeared in seventy-first days. L455f and f456l mutations occurred on day 106, and d427y and n501y mutations occurred on day 190. The study pointed out that the virus evolution may be driven by the selection pressure of impaired neutralizing antibody response. previously, the emergence of alpha variant was the result of the inability to eliminate the virus in the infected individual. In August 2021, a team from the University of bath and the University of Edinburgh in the UK According to the latest research, if someone is infected with COVID-19 for more than a few weeks, the virus may evolve, which may lead to new mutations. "The space for virus evolution is bigger than we think." The researchers said.

and in South Africa, there are about 2 million 200 thousand untreated HIV positive HIV patients, of whom less than 200 thousand have been vaccinated against the new crown. According to the Ministry of health, South Africa has been vaccinated for 35.37% of the adult population, but the number of vaccinations has declined in recent days.

Kim Dong Yan suggested that the group with the highest priority vaccination should be strengthened. , it should be the people with immune deficiency, "maybe it can't be strengthened for the first time, but it needs to be strengthened twice." he explained that this problem had been found when the first wave of large-scale breakthrough infection appeared in the United States, that is, the immune deficient population did not produce enough antibodies after two injections. Moreover, for this special population, the strategy of immune enhancement should be analyzed in combination with each specific case, because each immune deficient individual is protected by the vaccine There are great differences in the situation. Only in this way can we eliminate persistent infection. Lu Mengji also said that with the continuous emergence of mutant strains, people with older age and immune deficiency are more affected, so they need to enhance immunity and take personal protective measures. in addition, experts pointed out that the current vaccine is still effective, and even if it fails, humans can develop a new vaccine in the short term. November 26 On the th, Moderna said that it was working rapidly to test its ability to neutralize new variants, and expected to obtain data in the next few weeks. AstraZeneca is also seeking to understand the impact of Omicron variants on its vaccine and is testing its antibody combination therapy against new variants. A spokesman for the company said: "AstraZeneca is studying the mutant Botswana and Aars Waed Ni, which will enable us to collect the real world data of vaccines against new varieties."

, with the advent of the new varieties, has tried to return to the normal world in the past two days and restart the "seal up". Although the World Health Organization warned on 26 that countries should not rush to implement travel restrictions, they should seek "Risk assessment and scientific methods"

. However, after the World Health Organization listed Omicron as VOC, the United States immediately announced travel restrictions on eight countries in Africa, including South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique and Malawi.

, Britain, France, Israel and other countries have already announced travel ban on parts of Africa, of which the United Kingdom has 2. On the 6 day, 6 African countries, including South Africa and Botswana, were listed on the red list while the British flights were suspended. Singapore, Japan, Malaysia, Philippines, Turkey, Egypt, Saudi Arabia, Bahrain and Jordan also announced new restrictions on visitors from the region.

is just now, the US governor of New York, Kathy Ho. (Kathy hochul) announced that the state had entered a state of disaster emergency from December 3. She warned: "although the Omicron variant has not been found in New York State, it is coming."

2023-03-22 10:04:47

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