Helminthic therapy is the use of certain medically prepared species of helminths to treat allergic and autoimmune diseases (source: www.ncbi.nlm.nih.gov/mesh/68061147, accessed 8/30/12). Helminths are roundworms, many of which live at least part of their adult life in the intestines of vertebrate animals. Many helminths were (and in some countries still are) part of the normal intestinal flora of the human gut for tens of thousands of years.
Helminthic therapy is the use of certain medically prepared species of helminths to treat allergic and autoimmune diseases (source: www.ncbi.nlm.nih.gov/mesh/68061147, accessed 8/30/12). Helminths are roundworms, many of which live at least part of their adult life in the intestines of vertebrate animals. Many helminths were (and in some countries still are) part of the normal intestinal flora of the human gut for tens of thousands of years. Helminths have now found their way back to the human gut, intentionally, for the treatment of such immune-related disorders as type I diabetes, asthma, rheumatoid arthritis, Crohn’s disease, ulcerative colitis, multiple sclerosis, eczema, inflammatory bowel disease (IBD), dermatitis, hay fever, and food allergies. This page describes the following issues:
- History of Helminth Therapy
- Clinical Practice of Helminthic Therapy
- Producers and Distributors of Helminths and Helminthic Therapy Products
- How to Find a Helminthic Therapy Expert
- Related Topics, Links and References
History of Helminth Therapy
In the late 1980s, a popular theory arose entitled “The Hygiene Hypothesis” to explain why people living in developed countries have a high prevalence of atopic, or allergic, disorders. The theory was put forth by David P Strachan in the British Medical Journal after he studied hay fever in British children (Strachan, David. “Hay fever, hygiene, and household size.” British Medical Journal. 1989 Nov; 299 (6710):1259–60). Essentially, the Hygiene Hypothesis states that the human immune system is dependent upon exposure to a variety of organisms, in particular helminths, for proper development and functioning. The reason for this is believed to be that we co-evolved with these organisms, because they have almost always been present in our bodies. The recent and relatively rapid removal of these organisms from our bodies by modern medicine is believed by many scientists to be a major factor in the malfunction of many people’s immune systems. Under controlled conditions, at least some helminth species interact with humans in highly complex and apparently beneficial ways, modulating the immune system in preliminary studies and positively impacting allergic and autoimmune diseases. In small quantities, the right species may more accurately be described as having a symbiotic rather than parasitic relationship with the human body. This positive relationship has been referred to as the “Old Friends” theory by Dr. Graham Rook, MD, Emeritus Professor of Medical Microbiology at University College London (source: www.microbemagazine.org/index.php/04-2012-home/4700-a-darwinian-view-of-the-hygiene-or-old-friends-hypothesis, accessed 8/30/12). Note that helminthic therapy is just one step in restoring the natural environment in our bodies. The growing probiotic industry and the availability of natural yoghurts are other attempts to expose our bodies, once again, to the naturally occurring microflora that used to cohabit our gastrointestinal tract.
Clinical Practice of Helminthic Therapy
THE SCIENCE OF HELMINTHIC THERAPY According to Joel Weinstock, MD, Professor of Medicine at the Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, recent science has revealed what may be a “perfect correlation” between the rise in allergic and autoimmune states and the timing of helminth eradication programs in industrialized countries (source: www.youtube.com/watch?v=JpxMUwSOYQY, accessed 8/30/12). It’s thought that the elimination of an entire class of co-evolved organisms from the human body, as was done with helminths in the early 20th century, may be at least in part what’s driving the current epidemic of allergic and autoimmune diseases in developed nations (ibid). Supporting this assertion, encouraging experimental research has already been performed and more is either being planned or is currently underway to test the use of helminths in the treatment of Crohn’s disease, ulcerative colitis, asthma, allergies, multiple sclerosis, autism, celiac disease and rheumatoid arthritis (source: www.clinicaltrials.gov, accessed 8/30/12).
SPECIES CURRENTLY IN USE AS THERAPY Two main helminth species have been used in formal studies, Necator americanus, or human hookworm, and Trichuris suis, or pig whipworm (http://www.ncbi.nlm.nih.gov/pubmed/19050918). A third species, Trichuris trichiura (human whipworm) has been mentioned in the medical literature as a therapeutic agent but has not been formally studied. However, P’ng Loke, PhD, Assistant Professor, Department of Microbiology, New York University, reported a case of an individual who self-treated for ulcerative colitis with T. trichiura and experienced remission of symptoms (http://www.ncbi.nlm.nih.gov/pubmed?term=loke%20trichuris, accessed 8/30/12 ). T. trichiura has been referred to by David Elliott, MD, Professor and Division Director of Gastroenterology-Hepatology at the University of Iowa, as a commensal organism (Sleisenger and Fortran’s Gastrointestinal and Liver Disease 9th edition, via MDConsult at: www.mdconsult.com/books/page.do?eid=4-u1.0-B978-1-4160-6189-2..00110-4&isbn=978-1-4160-6189-2&type=bookPage&from=content&uniqId=357891209-2, accessed 9/4/12). One species has achieved Investigational New Drug (IND) status from the FDA, and is being studied clinically in the U.S.: Trichuris suis ova, or TSO®, produced by Ovamed GmbH and made available for clinical trials by the U.S.-based corporation Coronado Biosciences. Necator americanus appears to have similar investigational status in Australia and the UK, as evidenced by use in authorized clinical trials in those countries.
You can also find more current research at the Helminthic Therapy wiki page at http://helminthictherapywiki.org
Producers and Distributors of Helminths and Helminthic Therapy Products
All three species mentioned herein are commercially available as treatments, however in the U.S., the Food and Drug Administration appears to have classified therapeutic helminths as biological agents, i.e. drugs. Thus far, no helminth has been approved by the FDA for use in humans, and only one (the non-human species, Trichuris suis) has been approved for clinical testing. Producers and distributors of helminths for medical use or research include the following sources:
- Autoimmune Therapies – www.autoimmunetherapies.com
- Biome Restoration Ltd – http://www.biomerestoration.com
- Symmbio – http://symmbio.com
- Tanawisa – https://tanawisa.com
- Wormswell – http://wormswell.com
- WormTherapy – www.wormtherapy.com
How to Find a Helminthic Therapy Expert
We have compiled a database of helminthic therapy experts for your convenience. Anyone with interest, knowledge or experience with helminthic therapy is encouraged to add your resources or contact information to this list, by contacting the Foundation.
Related Topics, Links, and References
The Helminthic Therapy Wiki – http://helminthictherapywiki.org is an independent, volunteer-led helminthic therapy website mounted by the online HT community. This is now the definitive source of information about all aspects of this therapy.
Helminthic Therapy Support group (Facebook) – https://www.facebook.com/groups/htsupport/ (3,000+ members)
Helminthic Therapy Forum (Yahoo) – https://groups.yahoo.com/neo/groups/helminthictherapy/info (2,000 members)
Scientific Publications & Presentations
Hanauer SB: Evolving Biologic Therapies for IBD (Medscape Conference Coverage, based on selected sessions at the: Digestive Disease Week 2004; May 15 – 20, 2004, New Orleans, Louisiana)
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Links & News Stories
International Biotherapy Society Hanauer SB: Evolving Biologic Therapies for IBD (Medscape Conference Coverage, based on selected sessions at the: Digestive Disease Week 2004; May 15 – 20, 2004, New Orleans, Louisiana)