Security is mostly a superstition. It does not exist in nature,
nor do the children of men
as a whole experience it.
Avoiding danger is no safer
in the long run than outright exposure.
Life is either a daring adventure, or nothing.
–Helen Keller

Once upon a time, I was a wholesome, healthy, teenage girl. There was nothing I would rather do than backpack with my family in the forest, and nothing I would rather drink than pure, rushing river water.
Little did I know that nothing in nature is pure.
I discovered early on in our family’s backpacking adventures that the appearance of water is deceptive. I had only to fill my canteen to learn that water, while as clear as air, is nowhere near as light as air.
I should have figured right then that there is more to water than meets the eye. But I didn’t. I didn’t understand that water, essential water, delicious water, could kill me. The water from the streams tasted so much better than the water from the tap. How could it not be better? Purer? Safer?
Instead of following that old backpacking mantra, Take nothing but photographs, leave nothing but footprints, I took home a bellyful of worms I’d sucked down with that pure, rushing river water I’d found so delicious. Once those worms found their way into my digestive track, they began to wreck havoc.
Those little squatters would devour over three month’s worth of progressively blander breakfasts, lunches and dinners. Every one of “my” meals would be followed by violent, punishing diarrhea.
Life with these new parasites was ugly. Really ugly. In the course of three months, I was reduced to a (barely) living skeleton. I had to drop out of school, and rely on visiting tutors. As I became progressively weaker, I would have to send my tutors home early; sitting up for more than fifteen minutes at a time became too strenuous a challenge.
At one point during the parasitic occupation, I had a nasty reaction to an antibiotic. My esophagus contracted. I did not like that sensation. I thought I was having a heart attack. I remember my dad driving me to the hospital, reaching 50 miles an hour in a 35 mph zone. I was touched by his efforts, but I found them unnecessary. I’d had a nice life, if a short one; a loving family, gorgeous scenery, delicious water. I was ready to die.
In a less developed part of the world, I probably would have died, if not that day, then soon after. I certainly would not have reached adulthood. But as it happened, my dad was speeding me toward the teaching hospital at Yale University. The hospital would eventually connect me to an IV to boost my nutrition. They would treat me with an all-purpose parasite-killer. I would survive. The worms would die.
It was a real Ivy-league outcome. A victory.
The odd thing was, even after the parasites were killed, I never felt fully recovered.
I would live to adulthood, but it would be an adulthood with multiple sclerosis, a degenerative, debilitating autoimmune disease. Was that better than the alternative?
You bet.
Back when I was ready to die, I’d had no idea of all I would have missed. Instead of feeling serene, I would have felt really sorry for myself. Life is good. Even life with MS.
If you’ve been paying attention, by now you’ve probably reached the following conclusion: worms are bad. That was my assumption, too.
Imagine my surprise, then, when my friend Martin, a neuroscientist, sent me an article from The Annuals of Neurology, Association Between Parasite Infection and Immune Responses in Multiple Sclerosis (1), which observes that in the battle against multiple sclerosis, worms are…good.
The study compared multiple sclerosis patients who had naturally occurring parasitic infections to multiple sclerosis patients without parasites. The patients with parasites showed significantly less neurological damage over the course of four and a half years than the patients without parasites. Apparently worms are good for something. They keep autoimmune malfunctions in check.
At first, I resisted this data. I’d hosted more than my fair share of parasites. Those nasty little worms hadn’t kept me from contracting multiple sclerosis. But on second thought, I realized I hadn’t been a very nice hostess; I’d served up some heavy-duty all-purpose parasite killer. All the creatures living in my gut, good worms or bad worms, had been effectively wiped out.
Until I read the article, I never thought that was a problem. But now I do. This is why. Human beings have been co-evolving with parasites for millennia. It’s only recently that we’ve acquired the ability to produce heavy-duty all-purpose parasite killers like the one that saved my life. And it’s only very recently that we are beginning to realize there could be a trade-off. Tiny studies of disparate autoimmune diseases are all reaching the same conclusion; the immune system is regulated by the worms in our gut. (2)
Epidemiological data supports these findings. There is almost no incidence of autoimmune diseases like multiple sclerosis in the developing world, where modern standards of hygiene have not yet impeded on the dark, fragile ecosystem we prefer not to discuss in polite company. (3)
Biodiversity may be endangered in an ecosystem we rarely stop to think about. (4) This may have far reaching consequences for our health.
As I learn more about the immune protective function of microscopic intestinal life forms, I have come to regard that heavy-duty all-purpose parasite killer I took so many years ago as a blunt weapon; a weapon of mass destruction. It may have spared my life, but by wiping out the diverse life forms in my gut, it may also have incidentally left me vulnerable to developing multiple sclerosis.
I am grateful that I didn’t die that long ago day when my father rushed me to the hospital. Dying very young and very thin is still the only option for far too many children in undeveloped nations. This remains unacceptable. But can we offer a better alternative than a longer lifetime with a debilitating disease?
I think those of us in developed nations should pause to investigate whether we have been trading one set of diseases for another. I expect we can find a third way; a way to preserve and/or reintroduce those worms that have co-evolved to boost our immunity.
A few bold researchers are investigating this option. The National Multiple Sclerosis Society is funding a study in Wisconsin to measure the safety and effectiveness of helminth (worm) therapy. http://clinicaltrials.gov/ct2/show/NCT00645749

This research gives me a lot of hope. We still know so little about Multiple Sclerosis; it’s encouraging to see work being done that has potential to address a cause. I have a gut feeling that they are on the right track.

Sources:

1. http://www.direct-ms.org/pdf/HygieneMS/Parasite%20infection%20MS%20Annals%20Neur%2007.pdf
2. http://www.the-scientist.com/article/display/57941/#ixzz1EWTokRoL
3. http://en.wikipedia.org/wiki/Hygiene_hypothesis
4.http://www.msrc.co.uk/index.cfm/fuseaction/show/pageid/2474
Further reading:
http://evmedreview.com/?p=92
Do worms protect us against autoimmune diseases? The epidemiological evidence is strongly suggestive.

http://en.wikipedia.org/wiki/Helminthic_therapy
Helminthic therapy, a type of immunotherapy, is the treatment of autoimmune diseases and immune disorders by means of deliberate infestation with a helminth or with the ova of a helminth. Helminths are parasitic worms such as hookworms and whipworms.