Lyme disease
The most common early sign of lyme disease is the appearance of a rash on the skin that looks like a "bull's eye". The rash begins as a reddened area near the area of the tick bite. As the rash gets bigger, it clears in the center and develops a red ring around the outer perimeter. Other symptoms include muscle or joint aches, stiff neck, headache, weakness, fever, swollen lymph nodes and other flu-like symptoms.
Update Date: 5/20/2008 Updated by: Jatin M. Vyas, PhD, MD, Instructor in Medicine, Harvard Medical School, Assistant in Medicine, Division of Infectious Disease, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.