Causes

Hard- and soft-bodied female ticks are believed to make a poison that can cause 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 paralysis is ascending -- that means it starts in the lower body and moves up. It is similar to that seen in Guillain-Barre syndrome and opposite that seen in botulism and paralytic shellfish poisoning.

Symptoms

Children with tick paralysis develop an unsteady gait (ataxia) followed several days later by weakness in the lower legs that gradually moves up to involve the upper limbs.

Paralysis may cause breathing difficulties, which may require the use of a breathing machine.

The child may also have mild, flu-like symptoms (muscle aches, tiredness).

Exams and Tests

The person will have been exposed to ticks in some way. For example, he or she may have been on a recent camping trip, live in a tick-infested area, or have dogs or other animals that can pick up ticks. Often the tick is found only after thoroughly searching the person's hair.

Finding a tick embedded in the skin and noting above symptoms confirms the diagnosis. No other testing is required.

Treatment

Removing the tick removes the source of the neurotoxin. Recovery is rapid following the removal of the tick.

Outlook (Prognosis)

Full recovery is expected following the removal of the tick.

Possible Complications

• Respiratory failure

When to Contact a Medical Professional

If your child suddenly becomes unsteady or weak, have the child examined promptly. Breathing difficulties require emergency care.

Prevention

Use insect repellents and protective clothing when out in tick-infested areas. Carefully check the skin after being outside and remove any ticks.

As a rule, if children are discovered to have ticks, it is a good idea to write the information down and keep it for several months. Many tick-borne diseases do not show symptoms immediately, and the incident may be forgotten by the time a child becomes sick with a tick-borne disease.

References

Diaz JH. Ticks, including tick paralysis. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 297.

Bolgiano EB, Sexton J. Tick-borne illnesses. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 132.

Update Date: 5/1/2012

Reviewed by: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.