Answers of the safety effectiveness of the new crown virus vaccine (3)

On July 23, the State Council's joint prevention and control mechanism held a press conference. The responsible comrades and relevant experts of the National Health and Health Commission attended the meeting to introduce the relevant situation of the safety effectiveness of the new coronary virus vaccine. Please pay attention to the hot Q & A of this conference!

How is the dosage of the new coronal virus vaccine determined?

△ Expert Group Leader of the Research and Development Class of Scientific Research Research Group, Wang Junzhi, Academician of the Chinese Academy of Engineering

my country ’s minor 3-17 adopts the same dose as adults, which are determined based on the data of clinical trials. In history, there are various vaccines, including the activated spinal ashginitis vaccine, rabies vaccine, hepatitis A and other vaccines. They are consistent with the results of clinical research and adult doses. It is safe and effective that children's use of the same dose as adults.

The MRNA vaccine of two foreign companies uses 30 micrograms and 100 micrograms, and children use one -third of the dose of adults. It is mainly based on its own characteristics of the vaccine and the results of clinical safety and effectiveness. Different technical routes produced by the production of immune response in the body due to different components, so there is no comparability in terms of dosage.

What is a vaccine inoculation and an occasional reaction, how to determine the occasional reaction?

△ △ Director of the Department of Diseases Medicine, the Fifth Medical Center of the PLA General Hospital, academician of the Chinese Academy of Sciences king Fusheng coupling reaction or puppet syndrome refers to the incubation period or state before the vaccine is vaccinated. The disease occurs after the vaccination is vaccinated. In fact, it often has nothing to do with vaccination, nor does it belong to the category of abnormal reactions.

In my country, in the case of a large population base, under normal conditions, about 600,000 people in my country are hospitalized for various diseases every day. The number of deaths reported in the country every day is about 20,000. Therefore, in the process of large -scale vaccine vaccination, a variety of occasional reactions occur. For this issue, we must have a clear understanding, and do not attribute some irrelevant diseases to the new crown vaccine because of the coincidence of time.

In fact, my country has established a set of mechanisms on the judgment of the coupling response (paroxysmal). When some abnormal reactions are suspected to be related to the vaccine, it is necessary to report it. And diagnosed, the expert group made a comprehensive analysis based on the vaccine conditions, vaccination conditions, disease conditions, and adverse reactions monitoring. Finally, it was determined whether it was an occasional reaction.

Why is there a breakthrough infection after a vaccine?

△ △ Director of the Director of the Fifth Medical Center of the PLA General Hospital, Wang Fusheng, an academician of the Chinese Academy of Sciences. occur Since the advancement of science and technology has made large -scale detection of nucleic acid detection, it has significantly increased the detection rate of breakthrough infection. This is a precedent that has never been used in the history of human infectious diseases. The breakthrough infection we detected now includes a large number of asymptomatic infections, and they are also contagious, so they are very meaningful for controlling the source of infection.

Second, the new crown virus itself is prone to genetic variations. The genes produced by the Omikon mutant strain and the upper respiratory tract cell receptor increase, the contagiousness is strong, and the incubation period is shorter. These factors are also conducive to the occurrence of breakthrough infections.

Third, breakthrough infection is related to the infection of the new crown virus through the human respiratory tract pathway. Because the upper respiratory tract (including mouth, nose, pharynx, throat) and lower respiratory tract (including trachea, bronchial, alveoli) mucosa contain cells that express virus receptors (ACE2), the virus and receptor can enter a large number of cells to copy a large amount of replication On the one hand, the human body can exhale (release) with the breathing process, and on the other hand, the virus can enter the blood and lymphatic circulation to other parts of the human body. In this case, there is a big difference in whether the human body has been vaccinated. The vaccine produced protective antibodies and immune cells. However, these antibodies and immune cells are difficult to gather on the surface of the mucosa surface of the respiratory tract such as oral cavity, nasal throat, bronchial, so they are still infected by viruses.

Although the vaccine will have a virus breakthrough, the vaccine has a significant protective effect. It can prevent diseases, prevent severe illnesses, and prevent death. Vaccination is still the most effective and economic means to prevent infectious diseases. It is not necessary to "vaccine can't prevent infection" because of breaking through infection. This view is incorrect and unscientific.

Activated vaccine technology is backward?

△ Zheng Zhongwei, director of the Science and Technology Development Center of the National Health and Health Commission, and the leader of the research and development of the research and development of the scientific research group, is not backward technology, but a mature classic technology. At present, spinal ashgone vaccines, hepatitis A vaccine, influenza vaccine, rabies vaccine, hand, foot and mouth vaccine, which are widely used worldwide, are all vaccines. This time, the research and development and production of the new crown virus vaccine has many technological innovation and process improvement.

MRNA vaccine technology rose in the 1990s. The earliest was used to develop tumor treatment vaccines. No products were approved to be listed before the new crown epidemic. The MRNA vaccine of the new coronal virus is the first time in history. Therefore, we can call the MRNA vaccine technology as new technologies. Activating vaccines and MRNA vaccines have their own characteristics. We must not be simply distinguished by advanced or backward.

Why not test the antibody detection?

△ Director of the Science and Technology Development Center of the National Health and Health Commission, research and development Zheng Zhongwei, the team leader of the class working group, is everyone The antibody detection is neither necessary nor feasible.

First, during the phase of animal experiments and human clinical trials, it has proven that my country's new crown virus vaccine has good immunogenicity, and the yang rotation rate of neutralizing antibodies after vaccination is close to 100 %.

Second, the lower level of antibodies to a lower level does not indicate that the vaccine has lost its protection. The neutralized antibody level after vaccine will gradually decrease over time, and it will drop to a lower level after a certain period of time, and it will not even be detected. However, the protection of vaccines, in addition to neutralizing antibodies, also depends on cellular immunity and immune memory. The level of antibody does not fully represent vaccine protection.

Third, the detection of protective antibodies needs to be performed in the P3 biosafound laboratory. The cost is high, the time is long, and it is difficult to popularize. To accurately detect neutralized antibodies, you need to take the blood and get the P3 biological safety laboratory to neutralize the experiment with the real virus. Such experiments can prove your neutralization of the antibody level. And now ordinary commercial detection testing boxes are difficult to accurately determine the neutralization of antibodies on the actual reality of new coronal viruses.

Fourth, large -scale antibody testing for vaccines has never been conducted at home and abroad in history. Other vaccines in history in history have proven the effectiveness of the vaccine during the clinical trial stage, and will not conduct large -scale antibody testing of the vaccination population.

In addition, judging whether a certain vaccine is effective, mainly through the early clinical trial data and the later real world research based on large -scale epidemic conditions. The large -scale vaccination in my country has passed the strict review of the state drug supervision institution. Three of them have been included in the emergency use of the World Health Organization. The safety and effectiveness of the vaccine are beyond doubt.

What is the safety of the new crown vaccination in my country?

△ Executive Vice President and Secretary-General of the Chinese Association Cumulative reports have been vaccinated with more than 3.38 billion doses of new crown vaccines The cumulative report was reported to 238,215 cases after vaccination, and the overall report rate was 7045/1 million.

In bad events in the report, 81.29%are generally reactions, 5.47%of abnormal reactions, 9.89%of paroxylogenes, 2.42%of the heart response of the heart, and suspected in vaccination errors account for 0.002%, and the remaining 0.93%cases are to be determined.

In general, my country's new crown vaccine general response, abnormal reactions, and severe abnormal reactions are lower than the level of reporting of other conventional vaccination vaccines nationwide in 2020. So far, countries that use my country's new crown vaccine in the world have not found vaccine safety issues. These data fully show that my country's new crown vaccine is very safe.

Source: Healthy China

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