Tick paralysis

Hard-bodied 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. The poison enters the bloodstream during this feeding process.

The paralysis is ascending. That means it starts in the lower body and moves up.

Children with tick paralysis develop an unsteady gait followed several days later by weakness in the lower legs. This weakness 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).

People can be exposed to ticks in many ways. For example, they may have gone on a 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 a person's hair.

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

Removing the tick removes the source of the poison. Recovery is rapid after the tick is removed.

Full recovery is expected following the removal of the tick.

Breathing difficulties can cause respiratory failure. When this happens, the body's organs do not have enough oxygen to work well.

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

Use insect repellents and protective clothing when in tick-infested areas. Tuck pant legs into socks. Carefully check the skin and hair after being outside and remove any ticks you find.

If you find a tick on your child, write the information down and keep it for several months. Many tick-borne diseases do not show symptoms right away, and you may forget the incident by the time your child becomes sick with a tick-borne disease.

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Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.