Lyme´s Disease with Erythma migrans. Erythema migrans is the telltale rash which occurs in about 70% to 80% of cases and starts as a small red spot that expands over a period of days or weeks, forming a circular, triangular, or oval-shaped rash. Sometimes the rash resembles a bull's-eye because it appears as a red ring surrounding a central clear area. The rash, which can range in size from that of a dime to the entire width of a person's back, appears between three days and a few weeks of a tick bite, usually occurring at the site of a bite. As infection spreads, several rashes can appear at different sites on the body. Erythema migrans is often accompanied by symptoms such as fever, headache, stiff neck, body aches, and fatigue. These flu-like symptoms may resemble those of common viral infections and usually resolve within days or a few weeks.