CDC Lyme disease home page.
Risk: In the United States, Lyme disease is mostly localized to states in the northeastern, mid-Atlantic, and upper north-central regions, and to several counties in northwestern California. In 1999, 16,273 cases of Lyme disease were reported to the Centers for Disease Control and Prevention (CDC). Ninety-two percent of these were from the states of Connecticut, Rhode Island, New York, Pennsylvania, Delaware, New Jersey, Maryland, Massachusetts, and Wisconsin.
Individuals who live or work in residential areas surrounded by tick-infested woods or overgrown brush are at risk of getting Lyme disease. Persons who work or play in their yard, participate in recreational activities away from home such as hiking, camping, fishing and hunting, or engage in outdoor occupations, such as landscaping, brush clearing, forestry, and wildlife and parks management in endemic areas may also be at risk of getting Lyme disease.
Black-legged ticks (Ixodes scapularis) are responsible for transmitting Lyme disease bacteria to humans in the northeastern and north-central United States. On the Pacific Coast, the bacteria are transmitted to humans by the western black-legged tick (Ixodes pacificus). Ixodes ticks are much smaller than common dog and cattle ticks. In their larval and nymphal stages, they are no bigger than a pinhead. Ticks feed by inserting their mouths into the skin of a host and slowly take in blood. Ixodes ticks are most likely to transmit infection after feeding for two or more days.
Prevention and Treatment: It is important to remember that prevention measures can be effective in reducing your exposure to infected ticks, and most patients can be successfully treated with antibiotic therapy when diagnosed in the early stages of Lyme disease. Visit the links below for more information on the following topics:
* Prevention and Control
* Questions and Answers
Other Tick-Borne Diseases: Information about other tick transmitted illnesses like Southern tick-associated rash illness (STARI), Babesia infection, and ehrlichiosis can be found at CDC Health Topics A-Z.
More on the History of Lyme Disease: Early in the 20th century, European physicians observed patients with a red, slowly expanding rash (called erythema migrans or EM), associated this rash with the bite of ticks, and postulated that it was caused by a tick-borne bacterium. Then in the 1940s, similar tick-borne illness was described that often began with EM and developed into multi-system illness. Later that decade, spirochete-like structures were observed in skin specimens leading to the use of penicillin for treatment.
Aware of these findings, a physician in Wisconsin diagnosed a patient with EM and successfully treated it with penicillin in 1969. In the mid-1970s, physicians observed clusters of children with arthritis in and around Lyme, Connecticut. Other clinical symptoms and environmental conditions suggested that this was a distinct illness probably transmitted by an arthropod. Researchers linked the presence of EM rash lesions to preceding tick bites and determined that early treatment with penicillin not only shortened the duration of EM but also reduced the risk of subsequent arthritis.
In 1982, spirochetes were identified in the midgut of the adult deer tick, Ixodes dammini (referred herein by its original name, the black-legged tick, Ixodes scapularis) and given the name Borrelia burgdorferi. Finally, conclusive evidence that B. burgdorferi caused Lyme disease came in 1984 when spirochetes were cultured from the blood of patients with EM, from the rash lesion itself, and from the cerebrospinal fluid of a patient with meningoencephalitis and history of prior EM. CDC began surveillance for Lyme disease in 1982 and the Council of State and Territorial Epidemiologists (CSTE) designated Lyme disease as a nationally notifiable disease in January 1991.
Barbour AG. Lyme Disease: The Cause, the Cure, the Controversy. 1996. The Johns Hopkins University Press, Baltimore, MD.
Benach JL, Bosler EM, Hanrahan JP, et al. Spirochetes isolated from the blood of two patients with Lyme disease. N Engl J Med. 1983;308:740-742.
Burgdorfer W. How the discovery of Borrelia burgdorferi came about. Clin Dermatol. 1993 Jul-Sep;11(3):335-338.
Burgdorfer WA, Barbour AG, Hayes SF, et al. Lyme disease--a tick-borne spirochetosis? Science. 1982;216:1317-1319.
Centers for Disease Control and Prevention. Appendix Methods Used for Creating a National Lyme Disease Risk Map. MMWR. 4 Jun 1999; 48(RR07);21-24. (Also available in PDF format [??] [742 KB, 39 pages].)
Centers for Disease Control and Prevention. Lyme Disease--United States. 1999. MMWR. 16 Mar 2001;50(10):181-185. (Also available in PDF format [??] [1.47 MB, 20 pages].)
Hellerstrom S. Erythema chronicum migrans Afzelius with meningitis. Southern Med J. 1950;43:330-335.
Nadelman RB and Wormser GP. Lyme borreliosis. Lancet. 1998;352:557-565.
Orloski KA, Hayes EB, Campbell GL, Dennis DT. Surveillance for Lyme disease--United States, 1992-1998. Mor Mortal Wkly Rep CDC Surveill Summ. 2000 Apr 28;49(3):1-11.
Rahn DW, Evans J eds. Lyme Disease. 1998. American College of Physicians, Philadelphia, PA.
Scrimenti RJ. Erythema chronicum migrans. Arch Dermatol. 1970;102:104-105.
Sood SK, Salzman MB, Johnson BJ, Happ CM, Feig K, Carmody L, Rubin LG, Hilton E, Piesman J. Duration of tick attachment as a predictor of the risk of Lyme disease in an area in which Lyme disease is endemic. J Infect Dis. 1997 Apr;175(4):996-999.
Steere AC. Lyme disease. N Engl J Med. 1989 Aug 31;321(9):586-596.
Steere AC. Lyme disease. N Engl J Med. 2001 Jul 12;345(2):115-125.
Steere AC, Grodzicki RL, Kornblatt AN, et al. The spirochetal etiology of Lyme disease. N Engl J Med. 1983;308:733-740.
Steere AC, Malawista SE, Hardin JA, et al. Erythema chronicum migrans and Lyme arthritis: the enlarging clinical spectrum. Ann Intern Med. 1977;86:685-698.
Steere AC, Malawista SE, Newman JH, et al. Antibiotic therapy in Lyme disease. Ann Intern Med. 1980;93:1-8.
Steere AC, Malawista SE, Snydman DR, et al. Lyme arthritis: an epidemic of oligoarticular arthritis in children and adults in three Connecticut communities. Arthritis Rheum. 1977;20:7-17.
Wang G, van Dam AP, Schwartz I, Dankert J. Molecular typing of Borrelia burgdorferi sensu lato: taxonomic, epidemiological, and clinical implications. Clin Microbiol Rev. 1999 Oct;12(4):633-653.
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This page last reviewed September 21, 2001
| Division of Vector-Borne Infectious Diseases | | National Center for Infectious Diseases | | Centers for Disease Control and Prevention| P.O. Box 2087 Fort Collins, Colorado 80522
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|Publication:||Pamphlet by: Centers for Disease Control|
|Date:||Sep 21, 2001|
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