传染病所引起的残疾和死亡可通过疫苗预防 ,疫苗预防被认为是在各种公共卫生投入中最经济有效的方法。然而 ,人们也注意到还没有一种疫苗完全安全或对所有接种者均能产生保护作用。不同个体的免疫系统有时对疫苗的反应出现差异 ,免疫接种后不能产生保护作用或出现常见的副作用? Disability and death from infectious diseases can be prevented through vaccination, and vaccine prophylaxis is considered as the most cost-effective way to invest in all kinds of public health. However, it is also noticed that none of the vaccines are completely safe or have a protective effect on all those who are vaccinated. Different individuals’ immune systems sometimes react differently to vaccines and do not have protective effects or common side effects after immunization?