http://www.kuro5hin.org/story/2006/4/30/91945/8971
I have had severe allergies all of my life. As a child I had hay fever so bad that my eyes would swell shut and mucus would stream from my nose. I would lie in a darkened room with a cold damp flannel over my face to quell the itching, almost inebriate from antihistamines. Spring was pure misery.
Obviously for the drug company that brings a new asthma therapy to market based on this research there is the potential for billions in revenue. Unfortunately even if they are successful in identifying the mystery compound the hookworm secrete it will take around ten years to bring it to market, assuming they are successful in proving efficacy and safety
So, hookworm and these other parasites are down-modulating some aspect of our immune system, the result is no asthma, hayfever and Inflammatory Bowel Disease in individuals with sufficient numbers of hookworm. In effect, hookworm infestation suppress hay fever, asthma, colitis, Crohn's disease and Inflammatory Bowel Disease (IBD).
I became infested almost immediately, it must have been either the first or second day I spent walking barefoot through the latrines. When one thinks of it this was an enormous piece of luck.
To ensure that my infestation level is not too high and that I do not become anemic I simply get tested for anemia after each additional quarterly infestation and watch closely for the symptoms. I take iron supplements and make sure I eat well. No problems so far.