Would you pay $4,000 to be infected with hookworm? This is an experimental treatment advertised on the Internet for allergies, asthma, inflammatory bowel disease, multiple sclerosis, and Sjogren's syndrome. I don't know whether it works. However, I found two clinical trials in progress and some promising results from animal studies.
If you have relapsing remitting multiple sclerosis and you're age 18 to 45, you may want to check out the clinical trial in the references. This is an open label study with no placebo control, so all participants will receive the experimental helminth egg oral therapy for free. The researchers will evaluate safety and effectiveness of the treatment compared to each subject's condition at the start of the study.
Helminthic worms are common parasites, especially in tropical developing countries. The Centers for Disease Control warn travelers to wear shoes and wash their hands before eating to avoid infection. Most infections have no symptoms, especially when only a small number of worms are present. These worms do not multiply in the human body and are not directly contagious. The eggs are excreted in the feces and must develop into larva in the soil before infecting another person. They can enter the body through the skin or in contaminated food.
Reference 1 reports success in treating animal models of rheumatoid arthritis, multiple sclerosis, type 1 diabetes, inflammatory bowel disease, anaphylaxis, and asthma with helminthic worms. They caution that more research is needed, because there are reports that helminths can sometimes make these disorders worse in humans.
The motivation for helminthic therapy is the hygiene hypothesis, which suggests that our immune systems malfunction and cause allergy or autoimmune disease because we are not exposed to enough infectious agents. The Internet advertisement below describes the product as a probiotic. Most commercially available probiotics are bacteria normally found in the intestines of healthy people. Lactobacillus acidophilus is the most popular, but some brands of probiotic supplements contain a wide variety of bacteria species.