Lyme Disease The History of Lyme Disease and Its Distribution in United States

Lyme disease is an infectious disease caused by the bacteria Borrelia burgdorferi. B. burgdorferi is transmitted to humans by a bite from an infected black-legged or deer tick. The tick becomes infected after feeding on infected deer, birds, or mice.

A tick has to be present on the skin for at least 36 hours to transmit the infection. Many people with Lyme disease have no memory of a tick bite.

Lyme disease was first recognized in the town of Old Lyme, Connecticut, in 1975. It's the most common tick-borne illness in Europe and the United States.

People who live or spend time in wooded areas known for transmission of the disease are more likely to get this illness. People with domesticated animals that visit wooded areas also have a higher risk of getting Lyme disease.

Cases of Lyme disease have varied from year to year but have steadily increased for the past 20 years in the United States.

Lyme disease is not common to all of the United States and occurrence is primarily concentrated in the Northeast and upper Midwest regions.