Lyme disease is an infectious disease caused by Borrelia burgdorferi bacteria. The bacteria are transferred to humans by tick bite, specifically by blacklegged ticks (commonly known as deer ticks). The condition is named for the location in which it was first described, the town of Lyme, Connecticut.

Lyme disease is caused by infection with bacteria rather than by genetic changes. The risk of developing Lyme disease is influenced by a variety of lifestyle and environmental factors that reflect how likely a person is to get bitten by an infected tick, such as where a person lives, how much time is spent outdoors, and the time of year. While there is no evidence that genetic factors play a role in susceptibility to Lyme disease, such factors may affect the severity of the disease, particularly whether antibiotic-refractory Lyme arthritis develops.

Lyme disease is the most common tick-borne illness in the United States. An estimated 300,000 new cases occur every year. Lyme disease occurs in areas in which blacklegged ticks are found, primarily the northeastern states (from Virginia to Maine), the upper Midwest (Wisconsin, Minnesota, and Michigan), and parts of California and Oregon. In these regions of the United States, the incidence of Lyme disease is 10 to 100 cases per 100,000 people each year.

Lyme disease cannot be inherited. The risk of certain complications of the condition may be influenced by inherited genetic factors, but the inheritance pattern is unknown.

Published Date: June 01, 2018Published By: National Institutes of Health