Please note: This information was current at the time of publication. But medical information is always changing, and some information given here may be out of date. For regularly updated information on a variety of health topics, please visit familydoctor.org, the AAFP patient education Web site.
Information from Your Family Doctor
FREE PREVIEW. AAFP members and paid subscribers: Log in to get free access. All others: Purchase online access.
FREE PREVIEW. Purchase online access to read the full version of this article.
Am Fam Physician. 2012 Jun 1;85(11):online.
See related article on Lyme disease.
What is Lyme disease?
Lyme disease is an infection that people get when they are bitten by deer ticks that carry a certain type of bacteria. The tick is about the size of a poppy seed or sesame seed. It typically must be attached to your skin for at least 36 hours to pass the bacteria to you. Ticks that are attached for less than 24 hours, and those that are not engorged are unlikely to pass the bacteria to you.
Who gets it?
It is most common in people who live in the northeastern or north-central United States, and in people who work or live in areas that have a large deer population. You can get Lyme disease any time of the year, but it most often happens in late spring and early summer.
What are the symptoms?
Lyme disease usually begins as a rash called erythema migrans (er-uh-THEE-muh my-grenz). It typically appears three to 30 days after a tick bite and can be found anywhere on the skin. The rash most often starts as a red spot that grows larger than 5 cm. Sometimes the rash looks like a bull's-eye (i.e., clear in the center).
You may have chills, fatigue, headache, muscle aches, neck stiffness, and joint pain. Some people may also have pain and swelling of the knee, drooping of part of the face, or chest pain. It is important for you to see your doctor if you have any of these symptoms, because they can also be related to other illnesses.
How is it diagnosed?
Your doctor will take a medical history and perform a physical exam. You may also need a blood test. If you have had symptoms longer than six weeks, and your blood test is negative, your symptoms are probably not caused by Lyme disease.
How is it treated?
Most of the time, taking antibiotics for one to three weeks will treat the Lyme disease. Some people with certain heart or nervous system problems caused by Lyme disease may need to be hospitalized.
How can I prevent it?
Be careful when walking in wooded or grassy areas. Wear bug spray, but be sure to read the instructions before using it. Check your skin for ticks, paying close attention to your head, armpits, and groin. If you find a tick, use tweezers to carefully remove it. It also helps to keep your lawn mowed, remove piles of leaves or wood from your yard, install a fence to keep deer out, and spray certain areas with pesticides.
Where can I get more information?
AAFP's Patient Education Resource
American Lyme Disease Foundation
Web site: http://www.aldf.com
Centers for Disease Control and Prevention
Web site: http://www.cdc.gov/lyme/
Infectious Diseases Society of America
Web site: http://www.idsociety.org/Lyme_Facts/
This handout is provided to you by your family doctor and the American Academy of Family Physicians. Other health-related information is available from the AAFP online at http://familydoctor.org.
This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.
Copyright © 2012 by the American Academy of Family Physicians.
This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact firstname.lastname@example.org for copyright questions and/or permission requests.
Want to use this article elsewhere? Get Permissions