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Lyme Disease - Topic Overview
What is Lyme disease?
Lyme disease is an infection that is spread by ticks. You can get Lyme disease if you are bitten by an infected tick. But most people who have had a tick bite do not get Lyme disease. It’s still important to see your doctor if you have a tick attached to you that you can't remove.
Lyme Disease - Cause
Lyme disease is caused by infection with Borrelia burgdorferi (B. burgdorferi) bacteria.
How the disease is spread
Lyme disease is spread when you are bitten by a tick that is infected with B. burgdorferi bacteria. When an infected tick bites you, bacteria travel to the tick's salivary glands and then into your body through your skin. It takes about 24 hours for a tick to attach itself to the skin and begin to feed. The tick generally must be attached to you for 36 to 48 hours in order for it to transmit the Lyme disease bacteria.
In the United States, the two types of ticks that carry Lyme disease bacteria are:
- Deer ticks , which spread Lyme disease in the northeastern and upper Midwest.
- Western black-legged ticks , which spread Lyme disease along the Pacific coast-mostly northern California and Oregon.
Dogs, cats, and horses can become infected with Lyme disease bacteria, but they cannot pass the illness to humans. However, infected ticks may fall off the animals and then bite and infect humans. Animals may develop symptoms similar to those seen in people, including fever and swollen joints. A vaccine for dogs is available in some states.
There is no convincing evidence that Lyme disease can be spread to humans by insects such as mosquitoes, flies, or fleas.
Find
out whether Lyme disease is contagious, and learn how
Lyme disease is common in the United States. It can also be found in Canada, Europe, and Asia.
What causes Lyme disease?
Lyme disease is caused by bacteria. Infected ticks spread the bacteria by biting people or animals.
Two types of ticks carry the Lyme disease bacteria in the U.S. They are:
-
Deer ticks
. They spread the disease in the
Northeast and Midwest. -
Western black-legged ticks.
They spread the disease along the Pacific coast, mostly in northern California
and Oregon.
Remove ticks as
soon as you notice them. Infected ticks usually don't spread Lyme disease until
they have been attached for at least 36 hours.
What are the symptoms?
One sure sign of Lyme disease is a round, red rash that
spreads at the site of a tick bite. This rash can get very large.
Flu-like symptoms are also very common. People in the early stages of Lyme disease may feel very tired and have headaches, sore muscles and joints, and a fever.
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