Lyme disease
a multisystemic illness caused by spirochete bacteria transmitted through the bite of an infected deer tick. Initial effects are a red rash around the site of the bite as well as flulike symptoms of fever, fatigue, headache, and body aches. If left untreated, the disease can result in arthritis; neurological symptoms (e.g., severe headache, temporary paralysis); mood changes; and problems with memory loss, concentration, and sleep. Its manifestation of physical, cognitive, and psychiatric symptoms makes it difficult to diagnose. The disease was first recognized in 1975 after a large number of children in Lyme, Connecticut, were initially diagnosed with rheumatoid arthritis.