The web-site of New Scientist magazine has an interesting article on parasites and children with auto-immune diseases, but you can understand this blog-entry without reading that article. Investigations of third-world children with auto-immune diseases, such as multiple sclerosis, have indicated that they sometimes do better against their diseases if they are infected with parasites.
As I understand the best efforts so far to explain this:
1. We evolved as parasite-ridden creatures.
2. Parasites have ways of suppressing our immune systems so that they can survive longer.
3. Our immune systems have adjusted to this by being set at higher levels than if we were some sort of organism which was created in a pure environment.
4. Consequently, when we are too free of parasites and other infections, our immune systems will be too active and too sensitive. Auto-immune diseases such as MS or rheumatoid arthritis will become more common.
There is a social message in this and also a theological/anthropological message. The social message, stated simply, is that we should beware of any efforts to isolate human beings from the dirt and reality of the natural world. I’m not advocating we abolish all sanitary efforts — not by a long-shot, but we should be wiser in choosing our means and also our goals. There is a lot to be said about this complex issue, but I’ll leave that task to others for now.
The theological/anthropological message can also be stated simply, though I’ve tried to develop it in detail in my various writings, especially my only published book to-date: To See a World in a Grain of Sand. We are not fallen creatures so much as we are creatures integrated into a world which is a struggle between forces of order and disorder.
The paragraph above still leads too easily to a misinterpretation that portrays us as being at war with our own world. Speaking as a Christian, I feel my task is not to war against God’s Creation, nor do I see Creation as being filled with evil spirits who war against us. Our task as God-centered human beings is to figure out our role in Creation, having faith that finding this role and fulfilling it as well as possible will put us in the proper relationship to our Creator and prepare us for life in the world of the Resurrected.