Dear Mike,
Thank you very much for your explanation. Now I see.
Have a nice weekend.
Jiang
Quote:
Originally Posted by MikeNewYork  There are three main ways to acquire immunity to an infectious disease:
1. borrow immunity from one's mother (passive immunity of newborns)
2. develop immunity after having a disease
3. develp immunity after a vaccination (simulates having the disease)
Your dictionary means that once one is immune, one cannot be infected. One way to develop that immunity to have a disease and recover from it. Then you can't get it again (at least for a while). |