Recently i have read a post on the probability of transmition of hiv from one person to another while doing oral sex or intercourse and i was surpised by the small risk.
And even if you get infected by the hiv, you don't necessarily develop aids...
But it is highly probable that most humans are infected by one or several kinds of parasitic worms and parasitic worms are known to be able to alter the efficiency of the immune system.
So is this a great masquerade to keep people sick ? Or is it because the money dictates the progress ?