Question

It is concluded that virus can't be killed. If they enter our body how they die. For example common cold does not remain forever. How they get killed?

Answer 1

A virus traveling through plasma or blood can be tagged for death by an immune cell and subsequently eaten by a macrophage. A virus can be broken apart immediately after entering a cell by highly acidic lysosomes, organelles that degrade trash and foreign invaders in mammalian cells. However, the method by which every virus “hopes”- or is genetically programmed- to die, is by entering a host cell nucleus and delivering its genome. The virus capsid, or protective protein shell is degraded either during or subsequent to this process. Thus, the individual particle ceases to exist, but it's genome hijacks the host cell’s nuclear machinery to make many more viruses. Almost like a Phoenix, but instead of resurrecting itself it resurrects 10x over.