Lyme Disease Overview

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Lyme disease is an inflammatory disease characterized by a skin rash, joint inflammation, and flu-like symptoms. The disease is caused by the bacterium Borrelia burgdorferi, which is harbored and spread by deer ticks when feeding on a host. Deer ticks prefer the blood of mice, small birds and deer, but will also feed on humans, cats, dogs, and horses. Not all deer ticks are infected with the bacteria that cause Lyme disease, and only a small percentage of people or pets bitten by deer ticks actually become sick, but it is still important to take preventative measures against contracting the disease.

Lyme disease received its name from the town in which it was first reported, Old Lyme, Connecticut. The disease was first reported in 1975, but has now been reported in most parts of the United States. Most cases occur in the Northeast, upper Midwest, and along the Pacific coast. Ticks live in low bushes and tall grasses of wooded areas, waiting for warm-blooded animals to pass by, and are most active in the summer; though infections occur in the late spring and early fall as well.

If left untreated, Lyme disease can spread to joints, the heart, and the nervous system, so it's important to contact a health care professional as soon as symptoms develop, or as soon as you realize you've been bitten by a tick.

There are more than 16,000 cases of Lyme disease per year in the United States.

The risk factors for Lyme disease depend on your location, profession, and type of activities you participate in, such as walking in high grasses or walking a pet that may carry ticks home.

The most common risk factors for Lyme disease include:

• Spending time in wooded or grassy areas. In the United States, deer ticks are most prevalent in the Northeast, North Central and Northwest. All have heavily wooded areas where deer ticks thrive. In these regions, children who spend a lot of time outdoors, people with outdoor occupations, and those who live where mice are common are especially at risk.
• Having exposed skin. Ticks attach easily to bare flesh. In areas where ticks are common, protect the skin by wearing long sleeves and long pants. Don't allow pets to wander in tall weeds and grasses.
• Not removing ticks promptly or properly. Bacteria from a tick bite can enter the bloodstream only if the tick stays attached to the skin between 36 and 48 hours or longer. If a tick is removed within two days, the risk of acquiring Lyme disease is very low.