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lyme disease

Image: Lyme Disease
Lyme disease is a bacterial infection caused by the bite of an infected blacklegged tick, also known as the deer tick. It is the most common vector-borne illness in the United States and prevalent in Wisconsin. For purposes of monitoring illness, persons living in Dane County diagnosed with Lyme disease are reported to Public Health of Madison and Dane County Health by physicians and laboratories.

signs and symptoms

Signs and symptoms of Lyme disease can vary among individuals and not everyone experiences all of the symptoms listed. It is important to remember that not all ticks are infected with Lyme disease and transmit disease. The tick usually needs to be attached for at least 24 to 48 hours and likely be engorged.

Common symptoms of Lyme disease to watch for after the bite of a blacklegged tick are:

Early Stage or approximately three to thirty days after exposure:

  • A distinctive expanding rash occurs in 70% to 80% of cases, usually solid red or bull's-eye appearance at The site of the bite and persists for many weeks. Usually the rash is not painful or itchy
  • Fever
  • Chills
  • Headache
  • Muscle and joint pain
  • Fatigue

Early Disseminated Stage or approximately days to weeks after exposure:

  • Multiple rashes, not just at the bite site
  • Facial paralysis on one side of the face
  • Fever
  • Stiff aching neck
  • Headache
  • Weakness and numbness or pain in arms or legs
  • Irregular heart beat
  • Dizziness, light headed or heart palpitations
  • Persistent weakness and fatigue
  • Abnormal pulse

Late Stage or weeks to months after exposure:

  • Swelling and pain in one or more joints, usually the knee
  • Problems with neurological or nervous system
  • Persistent weakness or fatigue

how people get lyme disease:

  • Lyme disease is transmitted through the bite of an infected deer tick, which is found in wooded bushy areas throughout Wisconsin.
  • To find out about the number of reported Lyme disease cases in Wisconsin, and how it compares to other states, see the CDC Lyme Disease Case Maps.

prevention tips:

  • Avoid tick habitat. May through July is peak season for tick bites, but ticks may be out earlier or later. Deer or blacklegged ticks are found in moist wooded, brushy and grassy areas. Stay on trails and paths if hiking.
  • Use a good standard tick repellant. Apply especially on shoes, clothing and exposed skin containing no more than 30% DEET for adults and children following manufacturer's recommendations. Do not use on infants under 2 months. See more information about insect repellants.
  • Wear light colored clothing to easily spot ticks. Wear pants and long sleeves, and tuck pants into your socks or boots.
  • Check self, children and pets for ticks. Ticks like to find areas on the body that are protected, such as back of knee, groin, navel, armpit, ears or neck.
  • If you find a tick attached, remove the tick. Use a pair of tweezers with forceps type shape to grasp the tick by the head part not the body and apply firm and steady pressure to remove. Vaseline and burning matches do not work and are not effective in removing ticks. Once removed place tick in alcohol to kill it and clean the wound area with an antiseptic.

What to do if bitten by a tick:

  • If you removed the tick soon after it is attached, chances are very small of getting Lyme disease. Also, not every tick is infected with Lyme disease bacteria.
  • At the tick bite site, watch for an expanding rash that occurs frequently in Lyme disease for up to 30 days. Call your doctor if this occurs.
  • However, it is common to develop an area of inflammation and itching up to the size of a quarter immediately after the tick bite due to the irritation from tick saliva and is not a symptom of Lyme disease. If the tick is infected, the expanding rash will appear later. Not everyone develops a rash, or it may go unnoticed. It is important to be aware of other possible symptoms of Lyme disease if you spent time in tick habitat.

diagnosis and treatment:

  • Contact your health care provider if you suspect Lyme disease. Your health care provider may perform blood tests, a physical exam and check on your history of exposure. A blood test is not necessary for diagnosis of Lyme disease if the characteristic erythema migrans rash is present at the time of your visit. The blood tests are important if you have been ill for more than one month. The blood tests may be negative for two to three weeks after exposure.
  • Treatment: Certain antibiotics are very effective in treating Lyme disease. If treated later in the illness, antibiotics are very effective, but symptoms tend to take longer to disappear even though the bacteria have been killed. A small percentage of people continue to have complaints after routine treatment, please discuss this with your medical professional. Long term use of antibiotics could be detrimental to your health due to adverse side effects.

additional resources:

General Information:


Resources for Health Professionals: