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The Unlovable Desert-dwelling Kissing Bug Delivers a Powerful, Dangerous Smooch

For the second night in a row, a horrible itch pulls me from my sleep. Every hair follicle on my head burns and there's a numb ringing in my ears. Last night, an angry swelling the size of a walnut marked a bite on the inside of my arm. Tonight I feel a thick-ness in my lower lip. A kissing bug has fed on me again.

The kissing bug gets its name from its fondness for biting the lips of sleeping people, although the creature may choose to take its blood meal from other tender locations: necks, arms, backs, even eye-lids. Its other common name, the conenose bug, comes from its cone-shaped head and snout. This is the business end. The snout houses folding mouth-parts superbly designed for sucking large quantities of fluid through small holes. Some species can drink three times their body weight in only a few minutes of feeding.

The kissing bug belongs to an order of insects called Hemiptera, the true bugs, animals that include the familiar water striders and squash bugs. Hemiptera means "half-wings" and describes the triangular shield pattern on the bug's back. Another distinguishing feature, its balloonlike abdomen, tapers forward to bulging eyes and a tubular beak. Southwestern species may grow from a half-inch to an inch long.

Kissing bugs in the genus Triatoma range throughout North American deserts. Arizona counts several species three just in the Tucson area. Although the bugs will feed on other mammals (rock squirrels, skunks), wood rats, also called pack rats, remain their primary prey. A single wood-rat nest, looking like a mound of dead sticks and cactus joints, may support dozens of bugs.

Apparently the rodents can tolerate a conenose feeding frenzy. In a New Mexico study, researchers found 42 bugs in one wood-rat nest.

Kissing bugs, however, don't object to human blood when the opportunity presents itself. They've made their nocturnal withdrawals from me so many times that I'm convinced they prefer the taste of my precious B positive to anyone else's. I've sat around evening campfires with a dozen people only to have a kissing bug single me out, crawl into my shirt and work its piercing stylet across my back. I often wake to discover presents from a hungry conenose fat lips, knuckles disappearing into a swollen hand-while my wife sleeps comfortably only inch-es away, untouched. She tells me now that this ranks among the reasons she married me: I attract all the biting things that crawl around at night, and she's left alone.

Fortunately, a kissing bug bite has never sent me to the hospital. About a quarter of its victims experience serious problems, including vomiting, cramps, paralysis and some-times unconsciousness due to allergic reactions to foreign pro-teins in the bug's saliva.

And, as if allergic reactions weren't enough, some kiss-ing bugs carry Trypanosoma cruzi, the parasite that causes Chagas' disease. Named for Carlos Chagas, who first found the organism in human blood at the turn of the 20th century, the disease remains rare in the United States but affects 7 mil-lion people annually in tropical America.

The kissing bug transmits the disease inadvertently by infect-ing the bite site with its own droppings. Symptoms like fa-cial swelling, fever and anemia appear in one to two weeks. Un-treated, the disease may linger for years, finally resulting in heart failure. Some experts be-lieve that Charles Darwin be-gan suffering the wasting effects of Chagas' disease after visiting Peru in 1835.In Arizona, people can ex-pect nocturnal visits from kiss-ing bugs beginning around May when the winged adults search for new wood-rat nests to infest. Hunger primarily mo-tivates their flights, but high temperatures contribute. Porch lights also attract them. The bugs eggs, nymphs (small wingless replicas of their par-ents) and adults - become dormant with cooler weather (below 60°). Nymphs also feed on blood.

Now, at home, when I wake up at night with that familiar itch and ringing in my ears, I search diligently until I locate the culprit. And when I find a kissing bug gorged on my blood, I feed it to a large oscar, a fish I keep in my aquarium for that purpose. Even in my discomfort, I get some satis-faction from watching the fish dispose of the bug. It reminds me that, despite their feeding preferences, kissing bugs live nowhere near the top of the food chain.