According to AFP Washington, the American people will be vaccinated against the COVID-19 epidemic developed by Pfizer and Biotech from the 14th local time.
It is reported that the first batch of vaccines will be issued on the 13th local time, and people will receive the vaccine on the 14th. 145 supply points will be established throughout the United States on the 14th, an additional 425 on the 15th and 66 on the 16th. The number of people who were vaccinated in the first batch of vaccines would reach 3 million.
The Russian Satellite News Agency reported on December 13 that Alexander Ginzburg, director of the Russian Camalya Institute of Epidemiology and Microbiology, said that the immune protection period of the coronavirus vaccine “Satellite-V” may be about two years, and the vaccine protection period of Pfizer Pharmaceutical Company is four to five months, but these need to be It has been confirmed by experiments.
Zhou Song, China’s general legal adviser of biology, said at the China International Trade in Services Fair in September that a total of two doses of inactivated vaccine for Chinese biology need to be vaccinated at intervals of 2-4 weeks, and the possibility of vaccine protection is relatively high for one to three years.
They are all coronavirus vaccines. Why does the immune protection period range from a few months to three years?
Zhang Hongtao, an associate professor at the University of Pennsylvania School of Medicine, said in an interview with the Health Times that there are two factors affecting the immune protection period of vaccines, one is antibodies, the other is antigens.
After a person is infected with the virus, the activation of the human immune system will produce targeted antibodies, thus killing the virus. If the antibody degrades quickly and has a fast half-life, the immune protection time is short.
For example, the coronavirus vaccine previously developed by Pfizer, according to the disclosed data, three months after vaccination, it can be inferred that the level of antibodies in the body should have a protection period of at least half a year to one year, but this is only a speculative data. How long the specific vaccine protection period can last or needs to be verified through clinical trials.
On the other hand, the immune protection period is also related to the virus itself.
Some viruses can obtain very strong immune protection after infection once to achieve lifelong immunity. For example, the multiple vaccines we vaccinated in infancy can benefit us for life. But like flu vaccine, because its antigen changes every year, the flu vaccine needs to be administered every year.
Dr. Anthony Fauci, an infectious disease expert in the United States, has said that if the novel coronavirus is similar to other coronaviruses, its vaccine may not provide long-term immunity.
The expected validity period is about 3-6 months, and the maximum period is not more than 1 year.
The reporter inquired that the World Health Organization has set a “qualification threshold” for the protection period of the novel coronavirus vaccine in its “target product characteristics” document.
Under the conservation persistence column, the World Health Organization clearly states that “the key feature or minimum requirement is to provide at least six months of protection, and the ideal feature is to provide at least one year of protection.”
In addition, determining the immune protection period of the novel coronavirus vaccine requires observing a large number of people who have been vaccinated with effective vaccines to determine whether and when the infection rate of COVID-19 will rise with the vaccination time.
Zhang Yujiao, a tenured professor at Anderson Cancer Center, said in an article official account on the 12th, “Since most of the third phase of the vaccine research began in July this year, and the longest observation time is less than half a year, we can only determine that the validity period is more than half a year at present. As for how long it will it will take, we have to wait for the data to talk.
At the current state, it may be about a year, and hopefully longer.
