Viruses in real world are the most resilient creatures. A virus can survive under extreme conditions. if a living organism gets infected by a virus, it has to live rest of its life with the virus. The only thing one can do is to make the virus less active or more better make it freeze(in the same position).
Now, viruses that infect our PCs are also very robust,but here we can’t make them less active, we can ether freeze them(motionless) or destry them. The freezing thing can be called quarantine.
The problem with the other method, that of destruction is that, as viruses attach themselves to exes or important system files, virus destruction means, the destruction of the file which acts as its host. So in severe form of virus attack, one is left with no option, but to FORMAT, the drive which contains the Operating system.
