Who Would Have Thought: Parasites as a Treatment for Autoimmune Disease

Human whipworm eggs. Photo Kimberly Evanson, UCSF.

My first reaction to reading about this was a bit squeamish--they are going to treat people with autoimmune disease using the eggs of pig whipworms, but it is actually pretty interesting stuff.

The research is based upon the hygiene hypothesis which says that an increasing number of people in the Western world like the USA, Canada, and Britain are developing autoimmune disease, asthma, and allergies because we have become too clean.  These kinds of diseases are rarely seen in poorer or developing countries whose populations are still exposed to multiple parasites.  The theory goes that humans adapted to living with these parasites called helminthes over millions of years and that our immune systems came to depend on them.  Now that we no longer are exposed to parasites and other infectious agents with the development of indoor plumbing and modern medicine, our immune system can go haywire and into overdrive attacking things like cat dander in the case of allergies and our own tissue in the case of autoimmune disease.  According to Duke immunologist William Parker Ph.D., estimates are that about “4 in 10 Americans suffer from allergies and nearly 1 in 10 will develop an autoimmune disorder.”  Those are big numbers.

Small studies so far have shown promise with Crohn’s disease, ulcerative colitis, and multiple sclerosis. Participants take a tablespoon of saline with 2500 eggs once every two weeks.  While it doesn’t sound particularly appealing, the solution is tasteless and the pig whipworm eggs (Trichuris ova) cause the necessary immune response without any lasting infection.  The parasites die over a couple of weeks and are naturally discarded from the body.   In the case of multiple sclerosis for example, 4 out of the 5 patients participating in a small trial had a reduction in brain lesions when taking the egg solution and when they stopped taking it the number of brain lesions increased.  And in a larger trial with 29 people with Crohn’s disease, 70 percent of them went into remission after 6 months of treatment and 80 percent of them had a positive response.   Larger studies are in the works and some scientists have been working with hookworm as another parasite that might have similar outcomes.

For those of us with autoimmune disease, it sounds like the parasites might give the immune system something else to attack besides the body’s own cells and tissues.  One benefit to this kind of treatment might be that it is not a classic immunosuppressant that weakens the immune system and can also make people more prone to infections.   Who knows maybe there’s a chance in the not so distant future, some of us will be taking a cocktail of parasite eggs every couple of weeks to keep our immune systems in check.  If so, I would have to try not to think about what I am drinking. 

For more reading check out these links to my sources:

Scientific American Guest Blog, The Worms Within

Scientific American Guest Blog, Eating off the Floor: How Clean Living is Bad for You

Seeking Alpha, Should Biotech Investors Start Paying Attention To Parasitic Pig Worms And Autoimmune Diseases?

The Wall Street Journal, Parasitic Worms May Offer Hope on MS
Effect of Hookworm Infection on Wheat Challenge in Celiac Disease - A Randomized Double-Blinded Placebo Controlled Trial