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Lyme disease - primary - Overview

Alternative Names

Early localized Lyme infection; Lyme borreliosis; Stage 1 Lyme disease; Lyme disease - primary

Definition of Lyme disease - primary:

Lyme disease is an infectious disease spread through a tick bite.

Primary Lyme disease is the first stage of the disease. For specific information on the other stages or general information about Lyme disease, see:

Causes, incidence, and risk factors:

Lyme disease is caused by the bacteria Borrelia burgdorferi (B. burgdorferi). Certain ticks may carry the bacteria. The ticks pick up the bacteria when they bite mice or deer that are infected with Lyme disease. You can get the disease if an infected tick bites you.

Risk factors for Lyme disease include:

Having a pet that may carry ticks home
Taking part in activities that increase tick exposure
Walking in high grasses

The parts of the United States where the chance of getting Lyme disease is higher include:

New England
The mid-Atlantic states
The north-central states

Note: Deer ticks can be so small that they are almost impossible to see. Therefore, many people with Lyme disease never knew they had a tick bite. Unlike a mosquito bite, a tick bite cannot be felt. In most cases, the tick must stay on the body for 48 hours in order to transmit the bacteria to humans.

Lyme disease, erythema chronicum migrans

Lyme disease organism, Borrelia burgdorferi

Deer ticks

Ticks

Lyme disease - Borrelia burgdorferi organism

Lyme disease

Tick imbedded in the skin

Reviewed last on: 5/20/2008
Jantin M. Vyas, PhD, MD, Instructor in Medicine, Harvard Medical School, Assistant in Medicine, Division of Infectious Disease, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

References

Feder HM Jr., Johnson BJ, O'Connell S, Shapiro ED, Steere AC, Wormser GP. Ad Hoc International Lyme Disease Group. A critical appraisal of "chronic Lyme disease." N Engl J Med. 2007; 357:1422-1430.

Halperin JJ, Shapiro ED, Logigan E, Belman AL, Dotevall L, Wormser GP, et al. Practice parameter: treatment of nervous system Lyme disease (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 2007;69:91-102.

Wormser GP, Dattwyler RJ, Shapiro ED, Halperin JJ, Steere AC, Klempner MS, et al. The clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America. Clin Infect Dis. 2006;43:1089-1134.

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