Walsh & Hoyt: Lyme Disease

Lyme disease is a tick-borne spirochetal infection that is the most commonvector-born e disease inthe United States. It was first described in1977 after 39 children and 12 adults developed a unique, remittingrelapsing, oligoarticular arthritis that at first was thought to be a form of juvenile rheumatoid arthritis. The condition initially was called Lyme arthritis because the first cases were clustered inthree adjoining communities of Lyme, Old Lyme, and East Haddam, Connecticut, and because the main feature of the disease was the arthritis. It was renamed Lyme ""disease"" in recognition of its multi-system involvement, including the skin, heart, joints, and both the peripheral and central nervous systems. A tick vector from the Ixodes ricinus complex was identified shortly thereafter, and within a few years, a previously unidentified spirochete, Borrelia burgdorferi, was recognized as the causative agent. In retrospect, certain features of the disease, including the classic initial skin lesion erythema migrans and the peripheral nervous system findings had been described years earlier but the disease itself had not.