China News Service, December 19th. In response to the issue of the validity of the new crown vaccine, Zeng Yixin, the head of the vaccine research and development team of the Joint Prevention and Control Mechanism of the State Council and the deputy director of the National Health Commission, said on the 19th: "The protection period of the vaccine is based on the WHO For more than half a year as required by the regulations, there are basically not too many doubts.” After receiving the new crown vaccine, you should continue to maintain personal protective measures, including wearing masks, ensuring social distancing, and washing your hands frequently. The protective effect of the vaccine is not 100%.
Data map: Researchers are developing a new coronavirus mRNA vaccine.
Photo by Tang Yanjun
The State Council’s Joint Prevention and Control Mechanism held a press conference on the 19th to introduce the new crown virus vaccination work for key populations.
At the meeting, a reporter asked, what is the validity period of the three vaccines currently in use?
If the expiration date has passed, do I need to vaccinate again?
In addition, everyone may be concerned that if the new crown vaccine is given, should we continue to wear masks?
Zeng Yixin responded that the virus was discovered less than a year ago, so it is too early to say how long the vaccine can protect, and follow-up studies are needed.
However, there is some information that can help determine how long the vaccine will protect.
First, some animal experiments started in February.
At the Institute of Medical Laboratory Animals of the Chinese Academy of Medical Sciences, after vaccinating monkeys at that time, it proved that the vaccine can indeed protect the monkeys, and these monkeys are still there.
Recently, some experiments have been done to prove that it has a protective effect.
If it starts in February, it will be close to 9 months now.
The second is the Phase I and Phase II clinical trials launched in March. Many volunteers have conducted clinical trials and have been followed up to test their antibodies, and they are still there.
The third is that many medical institutions follow up recovered patients discharged from the hospital to see if the antibodies persist after discharge.
Zeng Yixin revealed that the first patient discharged from the Shenzhen Infectious Disease Hospital was on January 23. A total of more than 400 patients were followed up. They found that many patients still had antibodies for the longest 10 months.
"So these evidences suggest that the vaccine protection period is more than half a year as required by the WHO regulations. There are basically not too many doubts. Of course, can the protection period be like many viral vaccines that can be immune for life, or at least protect In five years and ten years, this conclusion cannot be drawn." Zeng Yixin said.
Is the new crown vaccine given once a year like the flu vaccine?
Zeng Yixin said, why is the flu vaccine given once a year?
It’s not because the influenza vaccine has a protection period of less than one year, but because the influenza virus mutates very quickly. This year may be this subtype is in the epidemic, and another subtype may be in the epidemic next year, so the vaccine must be adjusted at any time, not because of the vaccine. The protection period is one year, because the virus has mutated and different subtypes are circulating.
Therefore, it should be said that there is no need to re-vaccinate for half a year or a year. An optimistic estimate is unlikely.
Regarding the epidemic prevention measures after vaccination, Zeng Yixin pointed out that everyone should continue to maintain personal protective measures, including good habits such as wearing masks, ensuring social distancing, and washing hands frequently.
After all, the protective effect of vaccines is not 100%. So far, no vaccine has said that the protection rate is 100%.
Especially when the current herd immunity has not been established, even if the vaccine is given, the protective measures cannot be reduced.