Overview

Lyme disease, or borreliosis, is a bacterial infection transmitted by ticks to dogs, as well as other animals and people. It is caused by the spirochete Borrelia burgdorferi.

Most Lyme disease in the United States is spread by the deer tick, which is found primarily in the Northeast, Southeast, and upper Midwest. The western black-legged tick is the primary cause of Lyme disease transmission in the western states. No larger than the head of a pin, the ticks responsible for transmitting Lyme disease are smaller than most other ticks found on dogs.