natural immunization

• 自然免疫(作用)

natural immunization的用法和样例：

例句

1. The body has a hard time eliminating the bacteria completely, and natural immunity after a bout with the microbes lasts only about six months.
   一来人体不易将它们给驱逐殆尽，再者染上一回披衣菌所产生的自然免疫，也只能维持六个月左右。