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By Root 786 0

in chiggers. After tilting their body (somewhere between a forty-five-and sixty-degree angle), ticks use larger versions of the chelicerae found in mites and chiggers to scissor their way into a host’s skin, where they embed themselves. Ticks also attach themselves to a feeding site with a rodlike structure called a hypostome. Unlike the chigger’s feeding tube (stylostome), the hypostome of the tick is an actual body part through which blood is drawn from the host. Backward-pointing, hooklike projections on the hypostome prevent the tick from being easily removed. Additionally, in many tick species, the salivary glands produce a substance that literally cements the parasite to its host until it finishes feeding. Larval and nymphal ticks (which are often confused with chiggers) have smaller mouthparts and their bites are not as deep as those of the adult (which can penetrate past the epidermal and dermal regions of the skin into the underlying hypodermis).

Deeply embedded into their hosts, ticks breathe through an insectlike tracheal system, with the openings (also called spiracles) located on a section of the abdomen that remains above the surface of the host’s skin.*134

As Dr. Yeh explained, there are a few unexpected positives related to the transition from black-legged to Lone Star ticks in the northeastern United States.

“First of all, the bite of the Lone Star tick is more painful,” she said.

“That’s always a big plus,” I remarked, my mind wrestling with that one as I scribbled down notes.

“It makes them easier to detect,” Dr. Yeh continued, unfazed and exhibiting the patience that sometimes comes from working with the public.

“Right,” I said, trying to figure out a selective advantage for a tick to have a more painful bite—there didn’t seem to be any.

“Plus, STARI is milder than Lyme disease—although we don’t know a whole lot about it yet.”

“Starry?” I asked, trying not to sound like a bat biologist investigating tick-borne diseases.

“Southern tick associated rash illness. It’s caused by Borrelia lonestari, the bacterium transmitted by the Lone Star tick. STARI has similar symptoms to Lyme disease—fatigue, flulike stuff, and a rash.”

“What makes it milder?”

“It doesn’t appear to go chronic—no long-term effects like Lyme disease can have on the joints, nervous system, and heart.”

“Is there a test to distinguish between Lyme and STARI yet?”

The entomologist shook her head. “We haven’t got Lyme disease figured out yet—and now we’ve got STARI to deal with.”

“Why do the symptoms of Lyme vary so much?” I asked.

“If it isn’t treated early—and sometimes even if it is—many researchers believe that the flulike symptoms can give way to a menu of far more serious stuff later on.”*135

“Is it tough to diagnose?”

“That’s definitely one of the problems,” Dr. Yeh continued. “The blood test for Lyme disease is notoriously unreliable, and the disease mimics other maladies—arthritis and multiple sclerosis. And apparently there’s a latent form in which the bacteria that causes Lyme can hide in places like synovial fluid—where the host’s immune system can’t find it.”*136

As I interviewed Dr. Yeh, a debate was raging in the media and elsewhere among physicians, infectious disease researchers, bloggers, and various mothers-against-ticks groups over the existence (or nonexistence) of a chronic form of Lyme disease. Contrary to what Dr. Yeh believed, a growing contingent of physicians and infectious disease researchers find no evidence of a relationship between Lyme disease and long-term health effects. These professionals base their stance on recent studies that showed no trace of Borrelia in the spinal fluid, blood, and urine of well-documented Lyme disease patients who were acutely treated with antibiotics but complained of lingering symptoms months later.†137 Similarly, Dr. Lauren Krupp and her colleagues at Stony Brook University found that treatment of patients with long-term antibiotics produced results no better than with the placebo.

Those who opposed the concept of chronic Lyme disease offered several explanations