Viruses constantly reach our immune system, parasitizing our cage, aspiring to kill our organism.
That's where the problems start, viruses do not "aspire" to kill you, they're parasites for a reason....
Good parasites would want the hosts to live long , b/c if hosts die, they die. The viruses that kill an org quickly, like the ebola virus, doesn't get its progeny spread wide and easily either. they perish w/ hosts before hosts have chance to infect more
to be effective, these parasites would at least have to keep hosts alive long enough to achieve their "goals" like reproduction, expansion etc
i used to watch some episodes of the Stargate sci-fi show, many of you trekkies may be familiar w/ it, there's a "snake-like" parasitic worm called G'ould that infects the characters in Stargate, but the G'ould boosts hosts' immune systems and can increase humans lifespan from 70-80 yrs to like 200-300 years, but if they're removed, host dies soon too.
Edited by HYP86, 07 December 2008 - 04:30 AM.