The Domestic Vaccine Can Quickly Deal With The Mutated Strain, And The Difficulty Lies In Asymptomatic Infection

On May 30, Guangzhou and Shenzhen released the tracing results of this round of epidemic situation respectively: the gene sequencing results of the infected persons in Guangzhou city since May 21 were highly homologous, and they were all new coronavirus variants (b.1.617) found in India with extremely fast transmission speed; From the first to the eleventh cases in Shenzhen, the new coronavirus gene was highly homologous and belonged to the variant strain B117 found in the UK.

When it comes to dealing with virus mutation, Shao Yiming, a researcher at the Chinese Center for Disease Control and prevention and a consultant to the WHO vaccine research and Development Committee, said that a new generation of vaccine has been developed for the mutant strain, and the technical route of our country's inactivated vaccine is particularly suitable for rapid response to the mutant strain.

In addition, the new coronal vaccines of other technical routes in China also have protective effect on the mutant strains. For example, the preclinical research data just released by clover biology show that the recombinant protein new crown candidate vaccine will produce broad-spectrum neutralization antibody reaction against the original strain of new coronavirus and the mutant strain worthy of attention. According to the cross test results of neutralizing antibody, the new coronal vaccine is effective against the mutant strain.

It is worth noting that according to the published data, asymptomatic infection accounted for the majority in this round of epidemic.

On May 31, Hu Shanlian, a professor at the school of public health of Fudan University, said in an interview with the 21st century economic report that not all the flow surveys can be traced to the source.

Hu stressed that even if vaccinated, prevention and control should be strengthened“ Vaccinated people will produce antibodies and have immunity. Some people may not get sick after being infected with the virus and have no symptoms, but the virus they carry is still transmissible. Therefore, protection is still the key. After vaccination, people still need to wear masks and take protective measures. "

The vaccine is effective against the mutant strain

Following the rebound of epidemic situation in Liaoning, Anhui and other places, a new wave of epidemic situation caused by mutated strains has also appeared in Guangzhou and other places recently.

On May 27, Zhang zhoubin, deputy director of Guangzhou Center for Disease Control and prevention, once pointed out that according to the current epidemiological report and investigation, the epidemic situation has two characteristics: one is the transmission caused by infection in relatively closed places such as living together, dining together and trusteeship, and there is a clear transmission chain between the infected people; Second, the virus spreads very fast and has a strong spreading power.

In an interview with the media recently, gagandip Kham, consultant of the working group on new epidemic situation of the Indian government, pointed out that b.1.617 is likely to be 50% more infectious than the mutant strain found in the UK.

Not long ago, Zhang Boli, academician of the Chinese Academy of engineering, told the media, including journalists from the 21st century economic report, that the epidemic situation in the world as a whole has not ended. It was originally estimated that after the extensive vaccination by the end of this year, it may gradually become stable or be basically controlled. However, the current situation in India reminds us that there are not only deep-seated reasons for the outbreak in India, Virus mutation is an important reason, and it is the mutation of two sites, which has an impact on the effect of the vaccine.

On May 20, at a press conference held by the joint prevention and control mechanism of the State Council, Wu Zunyou, chief epidemiologic expert of the Chinese Center for Disease Control and prevention, said that the World Health Organization classified virus mutations into three categories: the first category is "mutant strains that need to be vigilant", such as those found in the United Kingdom, Brazil and South Africa. The second category is called "mutant strains of concern". This mutation in India, which is the dominant strain currently prevalent, belongs to this concern. Other variants are "mutant strains that need no attention".

Scientists and researchers from all over the world are paying close attention to the variation of virus strains, and the R & D and production enterprises of new coronavirus are also carrying out relevant research and development. China's vaccine enterprises are also active in research and development, and have achieved certain results.

On May 18, 21st century business reporter learned from clover biology that its new crown candidate vaccine can induce a broad-spectrum neutralization antibody reaction against the original strain of neocoronavirus and the mutant strain worthy of attention.

The relevant person in charge of kangxinuo biology told the reporter of 21st century economic report that the current global three phase clinical data show that the overall protective effect of kangxinuo biological new crown vaccine is 65.7%. According to the cross test results of neutralizing antibody, the vaccine is effective against the mutant strain.

"We will pay close attention to the variation of the virus and observe the immune persistence and effectiveness of the vaccine against the mutant strain. Once a mutant strain with escape vaccine protection is found, the adenovirus vector technology route of kangxinuo biological has the ability of rapid industrialization, and can rapidly develop and produce products for new virus strains. " The person in charge said.

However, Liu Peicheng, a spokesman for Kexing holdings, stressed to the 21st century economic reporter that no matter what technical route is developed, it must be produced and verified if it is eventually applied“ The new coronavirus has not been able to establish a global unified recommendation, sharing virus strains, and direct production mechanism of replacement strains, which means that even if it is developed, it needs at least clinical verification before it can be put into use. "

Prevention and control should not be lax

Vaccination can effectively control the epidemic situation, but prevention and control is still very important, especially for asymptomatic infected people, which brings great challenges. In this round of epidemic, there are more asymptomatic infections.

Hu Shanlian pointed out to the 21st century economic reporter that not every epidemiological investigation can find out its source“ After all, it is still a small number of people who can really find out the obvious infection relationship. " Pay attention to asymptomatic infections, Hu added.

"People who have been vaccinated have immunity, but it is not ruled out that they will be infected, or if they have antibodies in their bodies, they will not have symptoms, but they may carry the virus. The virus carried by vaccinated people is also transmissible. Although the carriers are autoimmune, their contacts are likely to be infected, "Hu said.

For the follow-up prevention and control situation, Hu Shanlian said that at present, prevention and control is still very important, to improve the coverage of immunization. Li Haichao, vice president of the first hospital of Peking University and an expert in respiratory department, also told reporters of the 21st century economic report that the general principle of protection has not changed at present“ Wear masks and wash hands frequently. In the epidemic areas, attention should be paid to less gathering and ventilation. It is very important to reduce the aggregation of the mutated strains

?