According to the data released by National Health Commission, as of April 3rd, 136.677 million doses of Covid-19 vaccine were reported in all localities.
At present, five Covid-19 vaccines have been approved for use in China. What’s the difference between these five vaccines? Which variety is better? The expert responded.
According to the technical route, the five vaccines are divided into three categories:
One is inactivated vaccine, includeSinopharm Zhongsheng Beijing Company, Sinopharm Zhongsheng Wuhan Company and Beijing Kexing Zhongwei Company. Three inactivated vaccines produced;
The second is adenovirus vector vaccine, forTianjin kangxinuo company Production of adenovirus type 5 vector vaccine;
The third is recombinant protein vaccine, forRecombinant novel coronavirus vaccine (CHO cells).
What is the difference between the three technical routes?
"Inactivated vaccine is a vaccine prepared by a series of purification techniques after the live virus is killed by physical and chemical methods." Wang Junzhi, deputy head of the expert group of the vaccine research and development special class of the State Council Joint Prevention and Control Mechanism and academician of China Academy of Engineering, said that its main feature is that the composition of the vaccine is similar to that of the natural virus, and its immune response is strong, so it has good safety.The vaccine is relatively stable, can be stored at 2-8 degrees Celsius for two to three years, and is convenient to transport; Take two injections of immunization.
"Adenovirus vector vaccine is a live vector vaccine made by taking adenovirus type 5 as a vector, introducing Covid-19 antigen gene and making it through bioreactor." Wang Junzhi said that the vaccine preparation process is relatively simple, and the research and development costs and production costs are relatively low, because it was successfully developed on the basis of the original platform of Ebola vaccine for adenovirus type 5 in our country.Vaccine can induce antibody production and enhance cellular immunity; You can take a single needle immunization.
"Recombinant protein vaccine is to express the most effective antigen components in vitro by genetic engineering. In vitro cells are cells commonly used by engineering cell lines in biological products, similar to industrial fermentation, and finally made into vaccines. " Yan Jinghua, a researcher at the Institute of Microbiology, Chinese Academy of Sciences, said that the whole production process is a process of protein expression and purification, and there is no live virus involved, so the production process is safe and easy for mass production. From the past use process of recombinant protein vaccine and the previous experimental results, the safety of recombinant protein vaccine can be guaranteed, and the adverse reaction rate is relatively low.The vaccine is refrigerated at 2-8 degrees Celsius, which has low requirements for transportation and storage conditions; Take two or three injections of immunization.
Which vaccine is more effective?
Wang Junzhi said that the three routes of Covid-19 vaccine have their own characteristics. No matter what technical route is adopted, the most important thing is to develop a safe, effective and quality-controlled vaccine by combining the characteristics of antigen and pathogen, which is the key criterion for vaccine success.
He Qinghua, a first-class inspector of National Health Commission CDC, said that at present, all Covid-19 vaccines listed in China have been examined and approved by the drug regulatory authorities.Its safety and effectiveness are supported by certain data, so you can safely inoculate.
How to choose single needle and double needle?
Shao Yiming, a researcher at China CDC, introduced,For people who need to go to epidemic areas for temporary or urgent tasks, but don’t have enough time to wait, it is more suitable to inject single-needle adenovirus vector vaccine. In addition, single-needle inoculation can avoid the poor immune effect caused by failure to get the second needle for various reasons.
Single-needle vaccine also has shortcomings. Shao Yiming suggested that the immune response intensity induced by single-needle adenovirus vector vaccine is generally weaker than that induced by two-needle vaccine, and it is no problem in preventing early epidemic virus. When it is replaced by late mutant virus, the protection efficiency will mostly decrease. Therefore, when choosing a vaccine, we should make a comprehensive judgment and scientific decision according to the specific situation of the people to be protected and the latest monitoring data of local epidemic viruses.
Why is vaccination first for young people and then for the elderly?
According to an interview with Dr. Zhang Wenhong from CCTV News: ① The elderly are less socially active than young people and may not be easily infected; ② The main task of epidemic prevention and control in China is to prevent external import and internal rebound, and most people who are exposed to viruses, such as doctors, are young people; ③ The incidence of other diseases in the elderly population is high, which needs more clinical research data to support.
I don’t have to fight when everyone else has?
Wen Yumei, an academician of China Academy of Engineering and a professor at Shanghai Medical College of Fudan University, said that vaccine is the only weapon that can completely control an infectious disease. Vaccination not only protects individuals from the pathogens of infectious diseases, but also limits the spread of pathogenic microorganisms in groups.
She pointed out that it is a good time to get COVID-19 vaccine. Because there is no epidemic in China, and most people are in good health, vaccination can protect everyone well. "We should take precautions and protect ourselves first."
In view of the mentality of some people that "I don’t need to get vaccinated when everyone else has finished", Wen Yumei said that this is a misunderstanding. The immune barrier formed by the population (generally about 70% to 80% people need to be vaccinated according to the Covid-19 transmission coefficient) can effectively control the spread of the epidemic, but it does not mean that individuals will not be infected. "Others are vaccinated because others are protected. If you are not vaccinated, you still have the risk of being infected."
Reminder: Don’t believe this message.
Recently, people across the country received a short message signed "Center for Disease Control", saying that "COVID-19 vaccine can be vaccinated by appointment" and attached an appointment link.
At first glance, it looks realistic, but you can see the flaw if you look closely. Yes, this is a scam message. If you receive a similar message, don’t believe it! Please delete it at the first time, don’t click on the link inside, and don’t fill in personal information.
Source: Comprehensive from People’s Daily client, CCTV news, Workers’ Daily and Chutian Metropolis Daily.