Some viruses that invade the human body avoid destruction by the immune system by?

Answer 1

A lot of avoidance happens at the molecular level--you get viruses that imitate cells or different proteins/molecules, thereby avoiding detection.

Answer 2

The invading systems are any set of beliefs that cannot be questioned or tested - any religion or fixed ideology for instance. The immune system is also hydra-headed ---- the capacity to live with uncertainty, the curiosity to question, the awareness to observe, and the intelligence for critical skepticism. God had nothing to do with any of them. Perhaps if he had, we'd be better at it? But remember, he forbade Adam and Eve to eat the fruit of the Tree of Knowledge. Not a good start, and an even worse end.

Answer 3

Viruses can evade our immune system in several ways.

1. antigenic variation to avoid immune system recognition.
2. downreuglation of MHC I molecules so CTLs cannot recognize infected cells (though this may leave infected cells subject to NK cell killing)
3. downregulation of accessory molecules like adhesion molecules
4. infecting "immunoprivileged" sites
5. infecting cells of the immune system directly (HIV)