Health Topics for Infectious Diseases

Department of Internal Medicine: Infectious Diseases

Department of Internal Medicine: Travel Medicine

Lyme disease

Lyme disease is an infection that develops after being bitten by an infected tick. Not all ticks carry the infection. Lyme disease is most common in the Northwest, the Mid-Atlantic states, the North Central states, and coastal California and Oregon, although it has been reported in all 50 states. It is important to know whether infected ticks are active in your area in order to determine your risk for Lyme disease.

Most people who get Lyme disease are bitten by the infected tick in late spring, summer or fall. The ticks live on wild animals, such as mice, raccoons, deer, and most of the time on birds. They may also live on domestic animals such as cats and dogs. Ticks may climb on humans from leaf litter and low-lying vegetation, in wooded, brushy or grassy areas. Ticks cannot jump or fly. A tick attaches to an animal or human by direct contact. An infected tick that is attached for less than 36 hours is unlikely to transmit infection. If the tick is attached 36 to 48 hours or longer, it is almost certain that infection is transmitted. The more time you spend in a wooded, grass or marsh area, the more chance you have of being bitten by a tick and being exposed to the illness.

The first symptoms of Lyme disease can begin anytime from days to months after the bite. If you notice any symptoms of the disease, contact your healthcare provider.

Early symptoms of Lyme disease include:

• flu-like symptoms, such as body aches, chills, fever, headache, and fatigue
• a red rash at the site of the bite, occurring 3 to 32 days after the bite (The rash is usually not painful or itchy and may spread. It appears as a flat, reddened circular area with central clearing and resembles a "bull's eye" or target. About 75 percent of all infected individuals will have the rash.)

More severe symptoms may occur weeks, months, or years after a tick bite. These may include:

• severe fatigue
• chronic, painful arthritis
• heart problems and
• central nervous system symptoms, such as confusion, memory loss, difficulty concentrating, or facial paralysis

Women who are pregnant and have Lyme disease may pass the disease on to the baby. If you are pregnant or breastfeeding and have symptoms of Lyme disease, contact your provider for advice.

Fortunately, Lyme disease can be treated with antibiotics. It is important to get treatment as soon as possible. This lowers the chance of complications.

The best way to avoid being bitten by a tick:

• Avoid areas with leaf litter and low-lying vegetation in wooded, bushy or overgrown grass areas.
• Wear light colored long pants and long-sleeved shirts. Tuck pant legs into socks or boot tops to keep ticks from coming in contact with your skin.
• There are also insect repellents you can get at the drugstore that will help repel the ticks. Use insect repellent containing DEET.

If you are going to be outside in a high-risk area, be sure to check your clothes, skin, and your pets for ticks daily. Ticks are very small (the largest being about the size of a sesame seed). Make sure that you check carefully because they can be hard to see.

If you find a tick on yourself, it is important to take it off as soon as possible. If the tick is removed within 36 hours, the risk of getting Lyme disease is much lower.

To remove the tick:

• Grasp the tick with fine-tipped tweezers as close to the skin as possible. With a steady motion, pull the tick up and away from your skin. Do not be alarmed if the tick's mouth parts are not removed from the skin. The bacteria that causes Lyme disease is found in the tick's mid-body.
• Do not try to smother it with petroleum jelly, nail polish, gasoline, rubbing alcohol, or any other irritant.
• Do not burn the tick with a hot match in an attempt to remove it from your skin. These methods can increase the chance of injury or infection.

After the tick is removed:

• Wash your hands with soap and water and apply an antiseptic to the area of the bite.
• Monitor the site of the bite for a rash and for other symptoms of Lyme disease.

If you are at risk for getting Lyme disease or think that you may have Lyme disease, contact your provider.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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