The Lyme Disease Rash

In most cases, the first sign of infection with the bacterium that causes Lyme disease is the Lyme disease rash. This is usually a circular rash called erythema migrans, or EM. This rash occurs in approximately 70-80 percent of people infected with Lyme disease, and begins at the site of a tick bite after a delay of 3-30 days. A distinctive feature of the Lyme disease rash is that it gradually expands over a period of several days, reaching up to 12 inches (30 cm) across. The center of the rash may clear as it enlarges, resulting in a bull's-eye appearance. It may be warm, but is not usually painful. Some patients develop additional Lyme disease rashes in other areas of the body after several days.

 

Patients can also experience other early symptoms of Lyme disease, including:

 

In some cases, these may be the only symptoms of infection.