Lyme Disease Basics

Lyme disease is a potentially serious bacterial infection caused by the bite of an infected blacklegged tick (also known as the deer tick or bear tick). The disease affects both humans and animals. The Minnesota Department of Health is monitoring the spread of the disease across the state and working with residents to limit exposure to the ticks causing the disease.

On this page:
Fact Sheets
Transmission
Prevention
Signs and symptoms
Diagnosis
Treatment
Treatment following a tick bite
History
More from other web sites

Fact Sheets

• Lyme Disease Frequently Asked Questions
  Answers to frequently asked questions about Lyme Disease.
  
  
• Lyme Disease Brochure
  Three-fold printable brochure about Lyme disease and other tick-borne diseases.

Transmission

• Lyme Disease is one of several tick-borne diseases in Minnesota.
  
• In order to get Lyme disease, a person must be bitten by a blacklegged tick (also known as deer tick or bear tick) that is infected with the Lyme disease bacteria.
  • Remember– not all blacklegged ticks are infected with the bacteria, so not all blacklegged ticks transmit disease.
  • The tick must be attached for at least 24-48 hours to transmit the bacteria.
  • The chance of getting Lyme disease increases the longer the tick is attached.

Prevention

• Preventing Tick-borne Diseases
  Learn how to minimize your risk to Lyme disease and other tick-borne diseases.
  
  
  
• Lyme Disease Vaccine
  Sales of the Lyme disease vaccine Lymerix (the only Lyme disease vaccine for humans) have been discontinued.

Signs and symptoms

The signs and symptoms of Lyme disease vary among individuals.  A person may not have all of these symptoms. People often feel like they have "the flu."

• Three to 30 days after a blacklegged tick bite, look for:
  • A distinctive rash                     
  • Fever
  • Chills
  • Headache
  • Muscle and joint pain
  • Fatigue
    
    
• Days to weeks after onset of illness, one or more of these signs and symptoms may occur:
  • Multiple rashes
  • Facial paralysis on one side of the face
  • Fever
  • Stiff neck
  • Headache
  • Weakness, numbness or pain in arms or legs
  • Irregular heart beat
  • Dizziness, feeling lightheaded, or heart palpitations
  • Persistent weakness and fatigue
    
    
• Weeks to months after onset of illness, some of these signs or symptoms may appear:
  • Joint swelling from arthritis in one or more joints, usually the knees
  • Problems with the nervous system
  • Persistent weakness and fatigue

Diagnosis

• If a person suspects Lyme disease, he or she should contact a doctor immediately.
  • Diagnosis includes:
    • Physical examination (signs and symptoms, presence of a rash)
    • History of possible exposure to blacklegged ticks
    • Blood tests may be performed
  • A thorough physical examination and history of exposure are required for proper diagnosis and treatment. 
  • Blood tests may be negative within the first 2-3 weeks of illness. A blood test if not required for diagnosis of early Lyme disease when the characteristic rash is present. The blood test is an important part of diagnosis for patients who have been ill for more than one month.
    
    
• Early recognition of signs and symptoms of Lyme disease is very important for prompt diagnosis and treatment.
  
  
• Early diagnosis and treatment can reduce the time a person is ill and the severity of the disease.

Treatment

• Here are a few general statements about the treatment of Lyme disease:
  • The disease is treated with antibiotics. Antibiotics are very effective in killing the bacteria.
  • Treatment is most effective early in the course of Lyme disease. Lyme disease detected later is also treatable with antibiotics, but can cause symptoms that may take longer to go away, even after the antibiotics have killed the Lyme disease bacteria.
    
    
• Most people have a complete resolution of their symptoms after treatment. A small percentage of patients (especially those diagnosed in the later stages of the disease) have persistent complaints after treatment.
  
  
• Specific questions about treatment should be discussed with your health care provider.

Treatment following a tick bite

• In some circumstances, a short (1-day) antibiotic treatment soon after a tick bite might prevent the development of Lyme disease. Several criteria must be met:
  • The tick must be identified as the blacklegged tick (deer tick).
  • The tick must have been attached for at least 36 hours (if it is engorged -- puffed up with blood -- then it was probably on this long).
  • The local infection rate in the blacklegged ticks must be at least 20%. This is likely the case for much of Minnesota, but call MDH (651-201-5414) if you have any questions.
  • The treatment must be started within 72 hours (3 days) of finding the attached tick on yourself.
  • The treatment is only for adults and children 8 years of older.
• Talk to your doctor about the single dose antibiotic treatment if you meet these criteria. You can also take a "wait and see" approach and watch for signs and symptoms of Lyme disease. Prompt treatment of the disease is very effective and will prevent more severe signs and symptoms.

History

• Lyme disease is the most common tick-borne disease in the United States.
  
  
• The disease was named in 1975, when a group of children in Connecticut were reported to have juvenile arthritis.
  
  
• The Minnesota Department of Health began collecting information on people diagnosed with Lyme disease in 1982. In 1985, Lyme disease became a reportable disease in the state.
  
  
• During the 1980s, the Minnesota Department of Natural Resources, Metropolitan Mosquito Control District, and other organizations were also participating in Lyme disease activities.
  
  
• During the 10-year period of 1999-2008, 7,692 confirmed cases of Lyme disease were reported in Minnesota.

More from other web sites:

• CDC Lyme Disease
  Centers for Disease Control and Prevention general information about Lyme disease. Attention: Non-MDH link
• Mayo Clinic Lyme Disease
  Fact sheet on Lyme disease. Attention: Non-MDH link
• American Lyme Disease Foundation
  Attention: Non-MDH link
• Occupational Safety and Health Administration (OSHA)
  • Potential for Occupational Exposure to Lyme Disease
    Attention: Non-MDH link

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