Lyme Disease | Overview


What is Lyme disease?

Lyme disease is an infection caused by a kind of bacterium (germ) called a spirochete (say: spy-ro-keet). The disease is carried by deer ticks (found in the northeastern and north-central United States) and western black-legged ticks (found mostly on the Pacific Coast). These ticks can spread the disease to animals and humans through tick bites. These ticks are typically about the size of a sesame seed.

 Lyme disease is most common in rural and suburban areas in the northeastern and midwestern states. Lyme disease is also found in other parts of the United States, as well as in Europe, Asia and Australia.

Written by editorial staff

Reviewed/Updated: 03/14
Created: 09/00