Lyme Disease

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Lyme disease facts

  • Lyme disease is a bacterial illness that is spread by tick bites.
  • Lyme disease can affect the skin, joints, heart, and the nervous system.
  • Lyme disease occurs in phases, with the early phase beginning at the site of the tick bite with an expanding ring of redness.
  • Lyme disease is diagnosed based on the patient's clinical signs of illness and the detection of antibodies to the causative bacteria in the blood.
  • Lyme disease is treated with antibiotics.

What is Lyme disease? What causes Lyme disease?

Lyme disease is a bacterial illness caused by a bacterium called a "spirochete." In the United States, the actual name of the bacterium is Borrelia burgdorferi. In Europe, the bacteria Borrelia afzelii and Borrelia garinii also cause Lyme disease. Certain ticks frequently found on deer from various locations harbor the bacterium in their stomachs. Lyme disease is spread by these ticks when they bite the skin, which permits the bacterium to infect the body. So Lyme disease is a tick-borne disease. Lyme disease is not contagious from an affected person to someone else. Lyme disease can cause abnormalities in the skin, joints, heart, and nervous system.

What is the history of Lyme disease?

Interestingly, the disease only became apparent in 1975 when mothers of a group of children who lived near each other in Lyme, Conn., made researchers aware that their children had all been diagnosed with rheumatoid arthritis. This unusual grouping of illness that appeared "rheumatoid" eventually led researchers to the identification of the bacterial cause of the children's condition, what was then named "Lyme disease" in 1982.

The only vector for Lyme disease in the U.S. is the deer tick known as Ixodes scapularis. These ticks are carriers of the Lyme disease bacterium in their stomachs. The ticks then are vectors that can transmit the bacterium to humans with a tick bite. The number of cases of the disease in an area depends on the number of ticks present and how often the ticks are infected with the bacteria. In certain areas of New York, where Lyme disease is common, over half of the ticks are infected. Lyme disease has been reported most often in the northeastern United States, but it has been reported in all 50 states, as well as China, Europe, Japan, Australia, and parts of the former Soviet Union. In the United States, it is primarily contracted in the Northeast in the states from Maine to Maryland, in the Midwest in Minnesota and Wisconsin, and in the West in Oregon and Northern California.

Picture of a deer tick
Picture of a deer tick
Medically Reviewed by a Doctor on 5/15/2014

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Lyme Disease Symptoms

Other signs and symptoms that may be associated with Lyme disease include the following:

  • Chills
  • Dizziness
  • Fever
  • Joint Swelling
  • Loss of Facial Muscle Tone
  • Swollen Lymph Nodes
  • Memory Problems
  • Muscle Pains
  • Numbness
  • Palpitations
  • Shooting Pains
  • Stiff Neck
  • Tingling

Some people may experience the following related Lyme disease symptoms and signs:

  • Rash
  • Joint Pain
  • Headache
Picture of characteristic bull's eye rash of Lyme disease