Currently, Bacille Calmette-Guerin(BCG) is still the only admitted vaccine to prevent tuberculosis around the world. The target population is infants and children, but its protective efficacy is limited. As more and more studies have shown that re-vaccination with BCG protects against tuberculosis in adults, BCG can also induce non-specific immunity against other respiratory diseases and some chronic diseases by training immunity, especially the immune effects against COVID-19. At present, the epidemic of COVID-19 has not been effectively contained, and it is worth considering whether BCG vaccine can be used as an intervention to prevent COVID-19. The WHO and China do not have a policy to support BCG revaccination, and as more and more BCG vaccines are discovered, whether selective revaccination can be carried out in some high-risk populations and whether the vaccine can be used more widely have led to intense discussions. This article reviewed the effects of specific immunity and non-specific immunity of BCG on tuberculosis and non-tuberculous diseases.
卡介苗是目前世界上唯一获准使用的用于预防结核病的疫苗，目标人群为婴幼儿，但是其保护时效是有限的。有研究证明，再次接种卡介苗可对成人结核病起保护作用；同时，通过训练免疫，卡介苗还可诱导产生非特异性免疫，对其他呼吸道疾病以及一些慢性病有积极的效果，尤其是针对新型冠状病毒感染（COVID-19）的免疫效果。目前，COVID-19的流行还未得到有效遏制，越来越多的研究证明卡介苗对预防COVID-19有积极效果，是否可以将卡介苗作为预防措施值得思考。世界卫生组织以及中国相关部门并没有提出支持卡介苗复种的相应政策，随着卡介苗的免疫作用越来越多的发现，对高危人群的选择性再次接种卡介苗以及是否可以将其更广泛的应用引起了激烈讨论。本文就卡介苗的特异性免疫和非特异性免疫作用对结核及非结核疾病的研究进展作一综述。.