Erythema chronicum migrans is characterized by an expanding erythematous band about an arthropod bite. While rare, it is an important disease to recognize because of its rapid response to even modest doses of antibiotics. This response and the association with arthropod bites suggest a microbial vector. Richettsial titers have been demonstrated in several cases but we were unable to show them in our patient, who we believe is the second reported case of erythema chronicum migrans incurred by an American without traveling abroad.