It was midsummer last year that I began to suspect I had Lyme disease. Listless, achy, loss of appetite. Eventually, a blood test confirmed the infection, and a three-week course of antibiotics supposedly cured it. But for several months, my blood stream swarmed with Lyme spirochetes, twisty bacteria squirming throughout my body.
Ponder for a moment the tiny bugs and microorganisms that live in us and on us.
They are everywhere: eyes, ears, teeth, gums, between the toes, in the groins. They harbor by the millions in the grasslands of the skin, the forests of the scalp, the damp Congos of the armpits.
Most densely of all, they thrive in the caverns of the digestive tract; in the lower part of the large intestine there are commonly 100 billion bacteria per gram of excrement.
They are the cause of body odor, bad breath and intestinal gas. They make our scalp and eyebrows itch. When their populations get wildly out of control they cause maladies such as yeast infections and thrush. But mostly they are harmless, and sometimes beneficial. Biologists call some of them commensal, which means in its Latin root, "eating at the same table."
Here's a neat imaginative exercise: Imagine that every one of your trillions of body cells, that is, the cells that are undeniably you, which bear your DNA, were to instantaneously vanish. There would remain (until it dispersed) a ghostly version of yourself, etched in space by your bugs -- your hair, eyebrows, ears and nostrils, fingers and toes, internal cavities -- and, maybe, if like me last summer, and maybe still, you were infected with Lyme pathogens, the entire web of your circulatory system would be outlined by a myriad of propellering bacteria, screwing through the air, wondering where their host had suddenly gone.