First, the validity period is limited. At present, most vaccines in China have a certain period of validity. In other words, after the vaccination, he can't guarantee your lifelong immunity. He can only maintain you for about half a year and achieve the effect of high-intensity immunity. After this time, its immune effect will decline.
Secondly, its function is not absolute. Although vaccination can achieve immunity to a certain extent, and the clinical research results are indeed true, it is not absolute and not applicable to everyone. There may be some people, because of their own physical conditions, the effect after vaccination is not obvious.
Of course, vaccination should be carried out anyway. Because we don't know whether it will work, but we should be prepared to work together. So I hope everyone can treat it positively and cooperate with the vaccination work. Only by quickly achieving universal vaccination can the impact of the epidemic be minimized.