◎ Zhang Jiaxing, reporter of Science and Technology Daily
According to the latest notification on the 23rd, the newly confirmed local cases in Guangzhou infected with the virus belonged to a variant strain that appeared in India.
Because of the more frequent mutations of the new coronavirus recently, “is the vaccine still effective?” has become a concern for everyone. If you want to add annual keywords to the new crown virus, then “mutation” is probably not inferior to “popularity.” “Preliminary research results show that my country’s existing vaccines can cope with the variant strains emerging in India.” Shao Yiming, a researcher at the China Centers for Disease Control and a member of the Vaccine R&D Team of the Scientific Research Group, said in an interview a few days ago that the domestic new crown vaccine still has a protective effect. . How can the domestic new crown vaccine be able to deal with the variant strains emerging in India? A reporter from Science and Technology Daily interviewed industry experts on this matter. The virus has changed Can the antibodies raised by the vaccine not drop? Today, when the antibodies in our body encounter the new coronavirus, it is very likely that we will whisper the phrase “you have changed.” In fact, it is difficult to stay the same, because it travels the world and meets different people and even animals. In the latest “Epidemiology Weekly Report” released by the World Health Organization on May 18, 10 variants were “named”, including 4 “needs of concern” that were first discovered in the UK, South Africa, Brazil, and India. The mutated strains also include 6 strains that “need attention” found in the Philippines, France and other places (slightly lower than the strains of concern). The report specifies the location of the virus mutation sequence change in detail. When the virus changes, can the antibodies raised by the vaccine fail to drop? Not necessarily, it depends on where the virus has changed. Most of the mutations of the concerned strains and the concerned strains fall on the key spike protein, which is responsible for allowing the virus to invade the cell. Its mutation may enhance the virus’s infectivity and may also invalidate existing vaccines, especially for the spike protein. Designed vaccine. “Relevant departments have previously shown based on sequence mutation predictions that although the mutation of the Indian strain falls on the spike protein, it may have little impact on the protective effect of the existing vaccine. Of course, this needs further experimental confirmation.” Said Lu Shan, project commissioner and deputy director of the Public Health and Modern Medicine Division of China Biotechnology Development Center, Ministry of Science and Technology. Changes in viral RNA sequence must pass at least three passes to affect the formation of a protein structure, including changes in coding amino acids, changes in protein folding, and changes in protein three-dimensional conformation. Therefore, from the perspective of sequence analysis, protein simulation, neutralization reaction prediction, etc., the mutation of the Indian strain has not reached the level of “cannot be reduced”. In addition, for the mutant strains that emerged in India, relevant departments are also conducting “practical drills” on them with neutralizing antibodies. Previously, similar studies were conducted on the mutant strains discovered for the first time in South Africa. “The Lancet-Microbe” published the results of two Chinese vaccines on April 13th. The 24 serum samples of vaccine subjects were tested for the neutralization activity of live virus, and wild-type virus strain HB02 and the virus strain BJ01 carrying the D614G mutation were used as controls. The results showed that the neutralization ability of the vaccine evoked antibodies was maintained at a percentage. It’s about sixty or seventy. Multi-party attention and continuous tracking of virus changes Shao Yiming said at the meeting that relevant departments and companies are closely following the mutation of the new crown virus. Once there are variant strains that cannot be dealt with by existing vaccines, we will have new vaccines into use. So, what does close tracking mean? If a new vaccine is needed, how quickly can it be developed? “Vaccine research and development teams continue to pay attention to virus mutations and carry out research and development of new vaccines based on virus mutations.” Lu Shan introduced, for example, the Academy of Military Sciences, Chinese Academy of Sciences, and related companies have gradually carried out. “The eighth edition of the prevention and control plan requires genetic sequencing of all imported cases and the first or early cases in the local epidemic.” Wu Liangyou, deputy director of the National Health Commission’s Disease Control Bureau, said at a press conference earlier that through gene sequencing dynamics Monitoring virus mutations can provide a scientific basis for subsequent studies on the impact of virus mutations on pathogen detection and vaccine protection. Source: Visual China These sequence information will be aggregated to the National Bioinformation Center (National Genome Science Data Center), the new coronavirus information database released by the center, which will continue to track virus mutations. The Chinese Center for Disease Control and other units continue to track the sequence changes of the new coronavirus and conduct in-depth virus mutation analysis. In addition to continuous gene sequencing and analysis for continuous tracking, vaccine research and development companies and research institutes will also conduct dynamic cross-protection experiments on newly emerging mutant strains. The above-mentioned “Lancet-Microorganism” published research is one of the typical studies of various units concerned about the strength of vaccines and viruses. For newly mutated strains, inactivated vaccines have a very quick way to deal with them. Shao Yiming introduced that as long as the virus of the new mutant strain is added to the feeding end, the entire production process does not need to be changed, and a new vaccine against the mutation can be produced. A reporter from Science and Technology Daily also contacted relevant units. In response, Dr. Hangwen Li, the founder of Sri Lanka Microbiology, said that the iterative vaccine development for mutant strains was carried out earlier. The serum produced in animal experiments can be tested by relevant national institutions to have a good neutralizing effect on the new coronavirus mutant strains of concern to the World Health Organization. At present, the iterative vaccine is improving related research applications to carry out a phase 1 clinical trial. Academician Zhong Nanshan judged in an interview not long ago: Due to the mutation of the virus, the new crown vaccine may be given regularly in the future like influenza prevention. So in response to mutations, the new crown vaccine may also be similar to the flu vaccine. After continuous research and development by the R&D team, several vaccines against variant strains of the new coronavirus have been produced, and the corresponding vaccines have been vaccinated. Source: Science and Technology Daily
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