Lyme disease(redirected from borreliosis)
Also found in: Dictionary, Thesaurus, Medical.
Lyme disease or Lyme borreliosis, a nonfatal bacterial infection that causes symptoms ranging from fever and headache to a painful swelling of the joints. The first American case of Lyme's characteristic rash was documented in 1970 and the disease was first identified in a cluster at the submarine base in Groton, Conn., by Navy doctors who reported their findings in 1976. It became more widely known and received its common name when it struck a group of families in nearby Lyme, Conn. In the United States the disease occurs mainly in the Northeast and parts of the Midwest among people who frequent grassy or wooded areas, but black-legged ticks are found in roughly half the counties in the United States. The disease is also prevalent in N and central Europe and temperate Asia. It is caused by the spirochetes of the genus Borrelia and is transmitted by black-legged, or deer, ticks of the genus Ixodes, which live on deer, mice, dogs, and other animals.
The bite of the tick injects the bacteria into the blood. A red rash develops, often circular with a bull's-eye appearance, followed by flulike symptoms (fever, headache, and painful joints). Most people are successfully treated with antibiotics. A small number develop chronic disease with neurological problems, memory loss, arthritis, and eye inflammation. Lyme disease is sometimes accompanied by babesiosis or human granulocytic ehrlichiosis, which also infect Ixodes ticks.
See also Rocky Mountain spotted fever.
See P. Murray, The Widening Circle (1996); A. Karlen, Biography of a Germ (2000); J. A. Edlow, Bull's-Eye (2003).
A multisystem illness caused by the tick-borne spirochete Borrelia burgdorferi. The disease, also known as Lyme borreliosis, generally begins with a unique expanding skin lesion, erythema migrans, which is often accompanied by symptoms resembling those of influenza or meningitis. During the weeks or months following the tick bite, some individuals may develop cardiac and neurological abnormalities, particularly meningitis or inflammation of the cranial or peripheral nerves. If the disease is untreated, intermittent or chronic arthritis and progressive encephalomyelitis may develop months or years after primary infection. See Nervous system disorders
The causative agent, B. burgdorferi, is a helically shaped bacterium with dimensions of 0.18–0.25 by 4–30 micrometers. Once thought to be limited to the European continent, Lyme borreliosis and related disorders are now known to occur also in North America, Russia, Japan, China, Australia, and Africa, where B. burgdorferi is maintained and transmitted by ticks of the genus Ixodes, namely I. dammini, I. pacificus, and possibly I. scapularis in the United States, I. ricinus in Europe, and I. persulcatus in Asia. Reports of Lyme disease in areas where neither I. dammini nor I. pacificus is present suggest that other species of ticks or possibly other bloodsucking arthropods such as biting flies or fleas may be involved in maintaining and transmitting the spirochetes. See Ixodides
All stages of Lyme borreliosis may respond to antibiotic therapy. Early treatment with oral tetracycline, doxycycline, penicillin, amoxicillin, or erythromycin can shorten the duration of symptoms and prevent later disease. See Antibiotic
Prevention and control of Lyme borreliosis must be directed toward reduction of the tick population. This can be accomplished through reducing the population of animals that serve as hosts for the adult ticks, elimination of rodents that are not only the preferred hosts but also the source for infecting immature ticks with B. burgdorferi, and application of tick-killing agents to vegetation in infested areas. Personal use of effective tick repellents and toxins is also recommended. See Infectious disease, Insecticide
Lyme disease affects not only humans but also domestic animals such as dogs, horses, and cattle that serve as hosts for the tick vectors. Animals affected show migratory, intermittent arthritis in some joints similar to that observed in humans.