With the continuous advancement of the new crown vaccination work, many people have successively received vaccination notices and made appointments for the new crown vaccination. However, some people think what will happen if there is no vaccine?
"People who have not been vaccinated will suffer!"
On March 23, Zhang Wenhong, director of the Department of Infectious Diseases, Huashan Hospital affiliated to Fudan University, said at the seminar site of the China Multidrug-Resistant Tuberculosis Ultra-Short Course Program Research Initiation Meeting: It will reopen. When the world’s major economies such as the United States, European Union countries, Japan, etc., are reopened, if our country continues to close, the impact on the economy and public psychology will be far greater than the new crown virus. Loss. When the door is opened, people who have not been vaccinated will suffer, and they will be very worried wherever they go."
Vaccination is the most effective way to prevent the new crown
Although everyone has their own special circumstances, the new crown vaccine is recommended. Moreover, according to the forecast issued by the Center for Infectious Disease Research and Policy (CIDRAP) of the University of Minnesota, the new crown epidemic may continue for several years or appear periodically and repeatedly. The WHO proposed that the vaccine will bring great hopes for reversing the epidemic, and my country The white paper "China Action to Fight the New Coronary Pneumonia Epidemic" issued as early as last year clearly pointed out the importance of striving to promote clinical trials and market use of vaccines as soon as possible. Experts on the front line of my country's national defense epidemic also expressed the hope that by the beginning of 2022 or even the end of this year, China will reach 70%-80% of the new crown vaccination rate and basically achieve herd immunity.
Undoubtedly, the new crown vaccine is currently the most effective means to prevent the new crown epidemic in the world. In particular, the vast majority of people in my country are susceptible to the new crown virus. Through the orderly vaccination of the new crown virus vaccine, an immune barrier can be gradually established in the population to block the new crown virus. The epidemic of pneumonia.
Why the new crown vaccine can be quickly developed and marketed
The research and development of vaccines needs to go through many tests such as research and development, animal experiments, multi-phase clinical trials, and marketing applications. Why does some vaccine development take 10 years?
This is because in the vaccine development process, scientific procedures must be strictly followed to complete each specific step. The R&D process before the application for registration of a light vaccine can not be finished at one breath, including: laboratory development (vaccine design/exploration), preclinical research (animal experiment), clinical trials (including phase I, phase II, and phase III). period). After the above-mentioned set of procedures is completed, usually several years or even decades have passed.
More importantly, after the vaccine is on the market, it will still be subject to strict supervision and evaluation. Once the clinical research results are not satisfactory, the previous efforts will be almost in vain and everything must be restarted from scratch. Therefore, vaccine research and development is an arduous task with extremely high investment, extremely long time-consuming, and extremely high risk.
But why can the development of the new crown vaccine be so fast?
On March 21, a review article published in the medical journal "American Journal of Translational Medicine" (AJTM) clearly pointed out the key reasons for the rapid advent of the new crown vaccine and introduced its true performance in the real world.
Researcher Dr. Hui Aimin, Chief Medical Officer of Fosun Pharma, explained this issue in detail in this review study. In short, his point of view has three main points:
- The power of technology has greatly accelerated vaccine research and development
The leapfrog development of science and technology has made the "lightning" of the new crown vaccine technically possible. For example, next-generation gene sequencing technology (NGS) can help researchers identify pathogens in a very short period of time and obtain the genome sequence of the new coronavirus; in addition, thanks to gene sequencing technology, Chinese research teams are receiving unidentified information from Wuhan. Cause After taking samples from patients with fever, it took only 10 days to obtain the entire genome sequence of the virus through high-throughput sequencing.
At the same time, the diversification of vaccine technology platforms has given us the ability to simultaneously develop traditional vaccines (inactivated vaccines, live attenuated vaccines), recombinant protein vaccines, viral vector vaccines, and nucleic acid (RNA and DNA) vaccines.
- We already have the research experience of coronavirus
The new coronavirus has brought misfortune to the world; but fortunately, due to the similarity between the new coronavirus and other coronaviruses (such as SARS virus, etc.), we have the experience of studying coronaviruses to learn from when developing vaccines, thus saving a certain amount of money. Development time.
In addition, the high transmissibility of the new coronavirus makes the infected population more common, and also enables the phase III clinical trial of the vaccine (which requires the participation of enough infected people) to start more quickly.
- All countries and enterprises all over the world cooperate with each other
Initially, Chinese researchers took the lead in obtaining the genome information of the new coronavirus. For the common interests of mankind around the world, they choose to selflessly share this resource with researchers from all over the world, thus greatly shortening the time required for the vaccine design phase of countries around the world.
Later, my country contained the development of the new crown epidemic in a short period of time. Facing the problem of insufficient number of subjects (new crown pneumonia patients) in the phase III clinical trials of domestic vaccines, at this time, through cooperation with other countries, enough recruits were recruited overseas. The number of new coronary pneumonia patients.
It is worth mentioning that many major companies in the vaccine industry are also working together. For example, BNT162b2 developed by BioNTech is the world's first mRNA vaccine. In March 2020, BioNTech and Fosun Pharma realized global cooperation, which promoted the domestic clinical trials and registration of the mRNA new crown vaccine, and also introduced BioNTech's proprietary mRNA vaccine technology into China.
What are the advantages of different types of new crown vaccines?
For the new coronavirus vaccine, it can be divided into inactivated vaccines, adenovirus vector vaccines and mRNA vaccines. In addition, there are recombinant subunits, synthetic peptides, DNA and other new coronavirus vaccines that are under development. Each vaccine method is different and its advantages are also different.
- Inactivated vaccine
Inactivated vaccines are the most traditional vaccine preparation method. Inactivated vaccine simply means that by injecting artificially inactivated pathogenic microorganisms or their metabolites (antigens) into the body, the human body generates antibodies against the antigen through recognition. Once it is invaded by a specific virus from outside, it stimulates the body’s immune system to produce Immune substances (antibodies) thereby resist the role of virus invasion.
Inactivated vaccine is a relatively mature technology with good safety, but its production cycle is longer (over 60 days), and its immunogenicity becomes weaker, requiring multiple immunizations and booster immunizations.
- Adenovirus vector vaccine
Adenovirus vector vaccines and mRNA are newer vaccines than inactivated vaccines. The adenovirus vector new coronavirus vaccine allows harmless adenoviruses to carry the new coronavirus to invade human cells with the S protein to make the body produce immune memory and stimulate the body to produce antibodies. However, as a new type of vaccine, adenovirus vector vaccines are currently less clinically used.
3.mRNA vaccine
The full name of mRNA is messenger ribonucleic acid, which can instruct human cells to produce antigens, thereby activating the human immune response and resisting the corresponding virus. It does not contain viral components and adjuvants, and there is no risk of infection or disease.
Our body's immune system mainly recognizes viruses through proteins on the surface of the virus. These proteins are called "antigens". Therefore, letting our immune system recognize and remember these antigens is the key. The advantage of mRNA lies in its ability to accurately express antigens, allowing our immune system to remember accurately.
After the human body is vaccinated with the mRNA COVID-19 vaccine, this blueprint will be safely delivered to the cells. These antigens produced by human cells can accurately activate the human body's immune system, and then immune cells can quickly recognize and eliminate the virus in a variety of ways. And the immune cells that remember these antigens will also rectify their equipment, increase their vigilance, and continue to quickly and accurately defend against the new coronavirus with the same antigen that may invade from the outside. In layman's terms, the mRNA COVID-19 vaccine is equivalent to handing over a detailed virus file to the body's immune system to accurately combat and eliminate the virus.
Where is the "magic" of the mRNA vaccine that quickly became popular?
As the third generation vaccine technology, mRNA vaccine is currently a technical route vaccine used by many western developed countries. The mRNA vaccine can accurately express antigens and activate the dual immune mechanism of "body fluid + T cells". It is highly immunogenic and does not require adjuvants.
At the same time, according to research, the overall protection rate of COVID-19 for people over 16 years old is as high as 95%. It can also produce effective antibodies against 20+ new coronavirus variants. And due to the short development cycle, new candidate vaccines can be quickly developed. Virus mutation, flexible change of antigen, timely response to virus mutation.
The mRNA vaccine is not only verified by phase III clinical trials of more than 40,000 samples from multiple centers around the world, but also certified by international authorities such as the World Health Organization. It can be widely used by people all over the world, including chronic diseases, pregnant women, etc. Special groups can be safely vaccinated. The latest WHO statement stated that there is no safety hazard in vaccinating the elderly and infirm with the BNT162b2 mRNA vaccine.
Because there is no need to synthesize proteins or viruses during development, the process is simple, and it is easy to mass produce. It supports the goal of global supply and is conducive to the advancement of global vaccination work.
Based on the advantages of mRNA vaccines, the World Health Organization (WHO) has approved the emergency use of mRNA vaccines. At present, 68 countries and regions including the United States, the United Kingdom, and Hong Kong have introduced mRNA vaccines. It is foreseeable that this new crown vaccine represents the world's leading nucleic acid vaccine route, and together with traditional technical route vaccines, it forms a joint array of vaccine research and development, which will bring dawn to the decisive victory of the global epidemic.