Home | List of Topics | General Medical Information | Infectious Diseases
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:
Early localized Lyme infection; Lyme borreliosis; Stage 1 Lyme disease; Lyme disease - primary
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:
The parts of the United States where the chance of getting Lyme disease is higher include:
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.
The first stage of Lyme disease is considered the "primary" or early stage.
Not everyone infected with the Lyme disease bacteria gets ill. Among those who do become ill, the first symptoms resemble the flu and include:
There may be a "bulls-eye" rash -- a flat or slightly raised red spot at the site of the tick bite often with a clear area in the center. This spot can be larger than 1 - 3 inches wide.
A blood test can be done to check for antibodies to the bacteria that causes Lyme disease. The most common one used is the ELISA for Lyme disease test. A western blot test is done to confirm ELISA results.
The tests are usually not positive in the first few weeks after the tick bite, so they are often not accurate early in the disease.
A skin biopsy can sometimes identify the Lyme disease bacteria.
Antibiotics are used to treat Lyme disease. The type of antibiotic used depends on the stage of the disease and your symptoms. The most common choices are doxycycline for older children and non-pregnant adults. Amoxicillin or cefuoxime (Ceftin) is typically prescribed for younger children.
Antibiotics are given for 10 - 21 days.
If diagnosed in the early stages, Lyme disease can be cured with antibiotics. The disease will usually get better in 3 - 4 weeks.
Without treatment, complications involving the joints, heart, and nervous system can occur.
If untreated, Lyme disease can progress to the advanced stages. Complications related to advanced Lyme disease include long-term joint inflammation (Lyme arthritis) and heart rhythm problems.
Nervous system (neurological) problems are also possible, and may include:
Another complication is infection with bacteria that cause other tick-borne infections, such as ehrlichiosis or babesiosis.
Call for an appointment with your health care provider if you have:
When walking or hiking in wooded or grassy areas:
Check yourself and your pets frequently during and after your walk or hike.
Ticks that carry Lyme disease are so small that they are very hard to see. After returning home, remove your clothes and thoroughly inspect all skin surface areas, including your scalp.
If possible, ask someone to help you examine your body for ticks. Adults should carefully examine children.
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.
Review Date:5/20/2008
Reviewed By: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.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.
Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.