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    Toxin From Tick Bite Paralyses Girl, Stumps Physicians


    Using the small black comb that is standard issue with other toiletries given to patients, Smith went section by section through the girl's hair. Stunning her colleagues, Smith discovered an engorged female tick stuck on the left side of the child's scalp.

    "I think I yelled, 'Hey, y'all!' when I found it," Smith tells WebMD. "Then I got all excited. We paged Dr. Felz and he came running up and helped us take it off." Michael W. Felz, MD -- who has researched tick-borne diseases for a decade and runs a national tick identification registry -- first photographed the tick, and then kept it in a warmed petri dish in his office.

    The tick found was not the kind that causes Lyme disease, but does carry Rocky Mountain Spotted Fever. If the tick is pregnant and feeding on a person, it produces an extremely potent toxin that can cause paralysis in humans and animals. Within 17 days, the tick produced 200 eggs. Both the tick and the eggs later died in Felz's office.

    For her part, the child recovered quite rapidly. "We took the tick off about 3:18 p.m., and I was on call that night so I was checking her," Smith says. "You could watch her improve. It was just amazing to watch. Her grandmother and her mother, they were just so thankful. Here she was almost on a ventilator. It was really dramatic."

    The child was hospitalized another 32 hours after the tick was removed, and subsequent neurological tests have been normal. Had the tick not been removed, it is likely that the paralysis that had first gripped her legs and then her arms would have continued ascending up her body, engulfing her lungs and making a ventilator necessary. The plasmapheresis, had it been performed, and any other aggressive interventions, would have been of no value.

    Ultimately, the tick would have finished feeding and fallen off on its own, Felz says, but in cases where the person is not placed on a ventilator, death may occur before that happens. There have been reports of ticks being found during autopsies of patients who died of unexplained paralysis.

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