Lyme disease is a tick-borne, bacterial disease which causes emotional and physical debilitation, leads to chronic arthritis -- even in children and young people -- and, in many cases, to heart problems. The disease has 3 phases in most patients: first, for several weeks, a skin rash with a red border around the tick bite; second, several days of fever accompanied by digestive problems and meningitis; and third, visual loss, arthritis or carditis.
Lyme disease is caused by the spirochete [Borrelia burgdorferi], named after its discoverer, Willy Burgdorfer. A spirochete is a spiral shaped bacterium. Other diseases caused by spirochetes include relapsing fever and syphilis. The ailment is named after the town of Old Lyme in Connecticut where it was first found in 1975. It commenced on the east coast of the USA and has spread to almost all states. Lyme disease is most commonly transmitted by a tick bite (usually painless). The tick vectors include the deer ticks [Ixodes scapularis] and [I. dammini], the Pacific tick [Ixodes pacificus] and the larger Lone Star tick [Amblyomme americanum]. In the UK the vector is the sheep tick.
In 1988, more than 5,000 cases were officially recorded in the USA, but this was officially declared a "dangerous underestimate". More than 16,000 cases of Lyme disease were reported in 1999, making it the most common illness transmitted by insects, ticks or spiders in the USA. Most cases are concentrated in about 115 counties in the eastern and north-central United States where animals (chiefly mice and deer) have high infection rates with the disease-causing bacteria, increasing the likelihood that a tick bite will transmit the infection to humans.