China Centers for Disease Control and Prevention: The new subtype of Omircor's strain has no obvious changes

Recently, Omikon BA.4 and BA.5 sub -branches have become the main popular strains in South Africa, Portugal and other countries. epidemic.

In this regard, Dong Xiaoping, chief expert of the China Centers for Disease Control and Control Center, responded to society. At present, data show that the spread of BA.4 and BA.5 Asian branches has increased significantly. Obviously, it is still a great threat to the elderly and basic patients. The main way of spreading is the spread of droplets. Do not despise it, and don't be too afraid. Standardizing wearing qualified masks is still one of the most effective preventive and control measures. The ninth edition of the new coronary virus pneumonia prevention and control scheme is still applicable.

Reporter: Is the communication between BA.4 and BA.5 mutations?

Dong Xiaoping: Omikon BA.4 and BA.5 mutant strains have indeed increased compared to previous. First, the incubation period is shortened, and the virus causes positive infected persons in a relatively short period of time, which means that it can be further disseminated by more detoxification. Second, research in some specific areas shows that in the case of no public security measures, the R0 values ​​of BA.4 and BA.5 variants are very high. Third, the BA.4 and BA.5 mutant strains have become superior strains in the United Kingdom, Denmark, Portugal and the United States, replacing other strains. From these three points, the transmission of BA.4 and BA.5 mutation strains is significantly higher than the Delta strain, and it is also higher than the previous Omikon mutant strains.

Reporter: BA.5 The pathogenicity of mutant strains is as strong as the original strain in the early morning?

Dong Xiaoping: At present, many research on the enhancement of pathogenicity is based on animal experiments. Although animal experiments are simulated human infections, there are certain limitations. There are still many differences between animal infection and human infection. For example, virus dose problems, and the characteristics of experimental animals are often single, and cannot simulate the infection of the whole population.

At present, we cannot conclude that BA.4 and BA.5 have stronger pathogenic conclusions than other mutant strains. BA.4 and BA.5 are not significantly different from the previous Omiko strains in terms of pathogenicity.

Reporter: Some netizens mentioned that people who have won new crown pneumonia have a greater probability of Omikon. What is the fact?

Dong Xiaoping: A large number of research results show that patients with the original strains still have the possibility of being infected by Omikon, but patients who have not said have a higher possibility of infection, or more serious clinical results Essence

Reporter: my country has released the ninth edition of the new crown pneumonia's epidemic prevention and control plan, and has made new requirements for the isolation time of secrets and entry personnel. Is it sufficient to deal with the BA.4 and BA.5 mutant strains?

Dong Xiaoping: Virus mutation is a common phenomenon in science. Only when the virus occurs very obviously, can it affect the effect of public health measures. At present, at home and abroad, there are no significant changes in public health measures for new crown viruses. The prevention and control measures in the ninth edition of the prevention and control plan should still be valid for BA.4 and BA.5 to be valid. I concluded based on the following two points:

First of all, the early version of the prevention and control scheme of the virus has increased to a higher level. When we were doing the prevention and control of viral diseases before, we paid attention to patients. Now, the forefront of prevention and control has been touched by almost everyone, and nucleic acid testing is an important means of prevention and control. The ninth edition of the prevention and control scheme reflects the tiered and layered detection strategies. The nucleic acid testing of high -risk people is very dense. Once an epidemic occurs, it can be found in time and measures.

Secondly, the requirements of the ninth edition of the prevention and control scheme on the secret and immigration personnel are required to change from 14+7 to 7+3 in the past, that is, the 7 -day centralized isolation+3 Heavenly Home Health Monitoring. We not only refer to the situation of other countries, but also from our observation of large -scale clustering epidemic in Shanghai and Jilin.

Reporter: As of July 18th, 31 provinces (autonomous regions, municipalities) and Xinjiang Production and Construction Corps have reported more than 3.4 billion doses of vaccine vaccine vaccines. So, is the existing vaccine still valid for Omikon BA.4 and BA.5?

Dong Xiaoping: This is a question that everyone is very concerned about. BA.4 and BA.5 mutant strains are basically the same on the most critical structural spiny protein in the new crown virus. There are not many cases of these two mutant plants in my country. Research data is needed to verify.

Internationally, there are only some limited data pointing out that BA.4 and BA.5 mutant plants will have some impact on the immune effects of vaccines, and these studies are mainly evaluated by in vitro neutralization and experiments. The protection effect of vaccine actually contains three levels: the first level, the protection effect of death and critical illness; the second level is the protection effect of hospitalization or explicit infection; the third level is the infection and further spreading prevention.

Existing research data shows that whether it is domestic surplus vaccine, adenovirus vector vaccine, or foreign MRNA vaccine, it has a good effect on preventing death for Omikon variants. , But the effect of preventing infection is indeed significantly reduced.

(Our newspaper, Beijing, July 19th. Reporter Jin Zhenya Yuan Yufei)

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