From the January 2001 Idaho Observer:

Do parasites run the world?

By the dawn of the 21st century people are being ravaged by a full spectrum of degenerative disorders and find it increasingly more difficult to recover from colds and influenza. We have found that many people realize a full recovery from their degenerative conditions and can radically boost their immunity to common maladies after ridding their bodies of parasites. And now we understand why.

By Don Harkins

The cover story for the August, 2000 edition of “Discover” magazine, “Do Parasites Rule the World?” by Paul Zimmer gives us some insight into how the presence of such tiny creatures in our bodies can determine whether or not we will have good or ill health.

The following excerpt from the Discover article places the parasite factor into proper perspective: “Every living thing has at least one parasite that lives inside or on it, and many, including humans, have far more. Leopard frogs may harbor a dozen species of parasites, including nematodes in their ears, filarial worms in their veins, and flukes in their kidneys, bladders, and intestines. One species of Mexican parrot carries 30 different species of mites on its feathers alone. Often the parasites themselves have parasites, and some of those parasites have parasites of their own. Scientists have no idea of the exact number of species of parasites, but they do know one fact: Parasites make up the majority of species on Earth. Parasites can take the form of animals, including insects, flatworms, and crustaceans, as well as protozoa, fungi, plants, and viruses and bacteria. By one estimate, parasites may outnumber free-living species four to one. Indeed, the study of life is, for the most part, parasitology.”

Parasites are the most numerous types of creature on Earth. New studies indicate that parasites are also the most influential creatures on Earth. The Discover article traces the reseach of a sceintist named Kevin Lafferty who set out to detemine how much influence a certain parasite has over an entire ecosystem.

Lafferty traced the path of a species of the fluke Euhaplorchis californiensis. He found that the fluke journeys through three hosts and plays a critical role in orchestrating the marsh's balance of nature: Flukes infest birds, the eggs of which are released in their droppings that are eaten by horn snails. The eggs hatch and grow in the snails and render them infertile. New fluke eggs hatch and leave the snail to find a new host -- the California killifish -- where they latch onto the fish's gills, crawl along a blood vessel to a nerve and up the nerve to the brain. There they wait until the fish is eaten by a bird where the cycle starts all over again.

Interestingly, Lafferty found that fish infested with the fluke are more likely to wriggle, flash and surface and are 30 times more liklely to become lunch for a bird.

Lafferty continued his experiments to find out how deep the parasitic influence ran in the marshy ecosystem he was studying. “Parasites don't just modify individual behavior, they're really powerful -- they may be running a large part of the waterbird ecology,” he said.

Most ordinary people as well as the scientific community have tried to dismiss parasites as biological freeloaders that are little more than an annoyance to their plant and animal hosts. However, when one considers that the quality of life can be restored to people who purge themselves of parasites and that parasites can determine which snails can reproduce and which ones cannot, we can no longer regard them as petty annoyances.

Recent research and experience shows that parasites are sophisticated, tenacious, resilient, prolific and can adapt to their environment with amazing ease. Once a parasite has taken up residence in a host, it can shut down its immune system, render it infertile and take control of its mind. “Some scientists now think parasites have been a dominant force, perhaps the dominant force, in the evolution of life,” wrote Zimmer.

Zimmer's Discover article concludes the subject of parasites brilliantly: “The notion that tiny creatures we've largely taken for granted are such a dominant force is immensely disturbing. Even after Copernicus took Earth out of the center of the universe and Darwin took humans out of the center of the living world, we still go through life pretending that we are exalted above other animals. Yet we know that we, too, are collections of cells that work together, kept harmonized by chemical signals. If an organism can control those signals -- an organism like a parasite -- then it can control us. And therein lies the peculiar and precise horror of parasites.”

If you happen to find your self suddenly fascinated with parasites, you can look at more photos of them online at: http://www.life.sci.qut.edu.au/LIFESCI/darben/figs/