A Lyme disease bacterium is carried in the deer tick (in the northeastern, mid-Atlantic, and north-central U.S.) and the western blacklegged tick on the Pacific Coast. In most cases, the tick must be attached 36-48 hours to spread Lyme disease. A circular, red, expanding rash (erythema migrans, or a “bullseye” rash) is one of the first symptoms of Lyme disease. Other symptoms include fatigue, chills, fever, headache, muscle and joint aches, and swollen lymph nodes. Treatment in the early stages with antibiotics is generally effective.