ParasitesRadiolab
http://www.wnyc.org/shows/radiolab/episodes/2009/09/25This 1 hour program discusses among other things the fascinating story of how the USA started getting oversanitized shortly before a big jump in autoimmune-related illnesses like asthma in the late 1800s and how Jasper Lawrence learned about the Hygiene Hypothesis and helminthic therapy and as a result put his asthma into remission by infecting himself with hookworm parasites, and he now sells hookworms.
Helminthic Therapy: How to put your Asthma, Colitis, IBD, Crohn's or Multiple Sclerosis into remission with hookworm.http://www.asthmahookworm.com/Summary
An important relationship exists between parasite infections and the development of atopic disorders. Long-lived parasite infections offer protection against atopic diseases like asthma, Crohn's disease, ulcerative colitis, multiple sclerosis and hayfever by immunosuppression. This knowledge is the basis for helminthic therapy, the deliberate inoculation or infection of an atopic individual with helminths to achieve remission for their disorder, such as those listed above. They induce modulatory molecules that ameliorate host responses to enhance their survival. The precise linking element's are not known but both eosinophils and IgE globulins that occur so prominently in both disorders may be crucial to this relationship. Understanding the immunology of the host-parasite interaction and identifying the distinct parasite molecules with the immunomodulating effects may help to combat allergy more successfully.
The hygiene hypothesis re-emphasized the inverse relationship between infection and allergy. Helminth research has once again provided key insights into the possible immunological explanation. The initial Th1-Th2 dichotomy provided the earliest immunological explanation for the hypothesis but there are major discrepancies. Several researchers have forwarded alternative immunological concepts in an attempt to better explain the original hygiene hypothesis. Modified Th-2 responses seen in parasite infections may provide protective 'blocking IgG4 globulins' that inhibit allergic responses. Protective programming of the fetal immune system by exposure to early infections or other environmental factors may be the critical factor against later atopic conditions. The identification of superantigens in the development of atopic skin lesions provides further insight into this interesting relationship. Research may well show that allergy is an unfortunate by-product of an evolutionary mechanism developed to combat bacteria, parasites and other organisms. We have come around in a full circle. Allergy started with the study of infections and today we still look at infections for answers to allergic conditions. The exact link between allergy and infection may provide a means of effective and successful treatment of these two important human problems. Alternative approaches such as the use of Mycobacterium vaccae, Th1 adjuvants such as IL-12 or the use of immunostimulatory nucleotides (CpG) are examples of potential new therapies
Parasite Rex by Carl Zimmer: Looks like a good book about parasites, including their beneficial effects
Hippity hop! Where to stop?, November 14, 2004
By Stephen A. Haines (Ottawa, Ontario Canada)
.... Zimmer cites Robin Dunbar's thesis that grooming for parasites ultimately allowed humans to develop speech and language. He explains how our immune systems and parasites enter a modus vivendi that allows the parasite and host alike to survive. Recognising how that process evolved could lead to better coexistence through "taming" the invaders.
Coexistence with these minute creatures turns out to have many implications. It's now clear that the development of agriculture made human society vulnerable to invaders unknown on the savannah. Human bodies became less robust and mortality rates rose. ....