Stage 1 begins with a characteristic expanding skin rash, which develops at the site of a tick bite as a small blister and expands in a circular manner over a number of days. As the rash expands, central clearing often occurs. Weeks to months after exposure, some patients develop heart or nervous system abnormalities associated with Stage 2 of the disease. The arthritis that represents Stage 3 of Lyme disease appears within several weeks to two years after Stage 1. Lyme disease morbidity is largely related to this arthritis which usually involves the knee.
Most cases occur during the summer and early fall.
The initial manifestation of Lyme disease may mimic many other disease entities. Lyme disease patients treated in early stages of the disease, when they only have a rash and flu-like symptoms, usually respond very well to therapy and recover rapidly. Permanent damage to joints occurs in a small number of patients whose disease is not successfully treated. Tuck pant legs into socks. Tuck shirttails in at the waist.