Embedded ticks can cause paralysis.
The letter quoted above began circulating on the Internet in June 2006. While we do not know the particulars of the incident it recounts and so can't confirm that it chronicles an actual event, what it describes is consonant with similar cases mentioned in medical literature:[CDC, 1996] On April 10, 1995, a 2-year-old girl who resided in Asotin County, Washington, was taken to the emergency department of a regional hospital because of a 2-day history of unsteady gait, difficulty standing, and reluctance to walk. Other than a recent history of cough, she had been healthy and had not been injured. On physical examination, she was afebrile, alert, and active but could stand only briefly before requiring assistance. Cranial nerve function was intact. However, she exhibited marked extremity and mild truncal ataxia, and deep tendon reflexes were absent. She was admitted with a tentative diagnosis of either Guillain-Barre syndrome or postinfectious polyradiculopathy. Within several hours of hospitalization, she had onset of drooling and tachypnea. A nurse incidentally detected an engorged tick on the girl's hairline by an ear and removed the tick. Within 7 hours after tick removal, tachypnea subsided and reflexes were present but diminished. The patient recovered fully and was discharged on April 11. The tick species was not identified. [Kocan, 1988] A 7-year-old girl was taken to her physician for evaluation of acute, ascending motor paralysis and speech difficulties. The girl's parents indicated that she had no history of motor difficulties and that the current symptoms developed quite rapidly. The family lived in a rural area, and the child often played in the woods accompanied by her pet dog. Results of laboratory investigations were not remarkable. A single engorged female tick was found attached to the girl's neck, and it was determined that the child had tick paralysis. Speech and motor function improved rapidly after the tick was removed, and the child recovered within hours and without complications.Tick paralysis is caused by a neurotoxin produced in the tick's salivary gland. As the University of Pennsylvania Health System's web site describes it:Hard- and soft-bodied female ticks are thought to produce a neurotoxin capable of causing paralysis in children. Ticks attach to the skin to feed on blood. It is during this feeding process that the toxin enters the bloodstream. The resulting paralysis is ascending (starting in the lower body and moving up) and is similar to that seen in Guillain-Barre syndrome and opposite that seen in botulism and paralytic shellfish poisoning (descending). Affected children develop an unsteady gait (ataxia) followed several days later by lower extremity weakness that gradually moves up to involve the upper limbs. Paralysis may cause loss of respiratory ability and the patient may require a ventilator. Symptoms: history of exposure to ticks such as camping, a tick-infested area, dogs or other animals finding a tick attached at the back of the neck at the hairline unsteady jerky body movements and gait (ataxia) muscle weakness beginning in the lower extremities and progressing upwards breathing difficultiesThe word ataxia, by the way, serves both as the name of a specific disease (actually, a group of diseases known as hereditary and sporadic ataxias) and as a general term meaning 'the loss of ability to coordinate muscular movement' (also known as dyssynergia or incoordination). The nurse in the story quoted above appears to have intended her use of the word as a description of some of the stricken child's symptoms, but the mother understood it as the name of her daughter's illness, hence her mention of ' ... disease with no cure, she would be wheel-chair bound the rest of her life and would never see her 20's.' More simply put, we note that:Tick paralysis is not ataxia. Ataxia (incoordination) is one of the effects of tick paralysis (in the same way that vomiting is one of the effects of food poisoning). Ataxia (disease: hereditary or sporadic) is unrelated to tick paralysis.Barbara 'dual-use words are a pistol' Mikkelson National Ataxia Foundation
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