Lyme Disease

Lyme Disease is a bacterial infection resulting from the bite of an infected deer tick.

Causes

Lyme Disease infection is caused by the bacteria Borrelia burgdorferi, carried by deer ticks. An infected tick transmits the bacteria to humans by biting the skin. If untreated, the bacteria is capable of traveling through the bloodstream, settling in various body tissues, and causing a number of acute and persistent symptoms, ranging from mild to severe.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.
  • Exposure to deer ticks
  • Living in the northeastern, mid-Atlantic, and upper north-central regions of the United States, and northwestern California. Peak tick season in the northeast is April through September, and on the West coast is November through April.
  • Participating in outdoor activities such as hiking, camping, and gardening
  • Living near or frequenting wooded, grassy areas
  • Working outdoors such as surveying, landscaping, forestry, gardening, and utility company service work

Symptoms

The symptoms of Lyme Disease can range from mild to severe, with not all symptoms developing. The majority of infected individuals first notice a red rash known as erythema migrans (EM). The rash starts as a small red spot at the site of the tick bite and expands over a period of days or weeks, forming a circular or oval shaped rash. Sometimes the rash resembles a bull's eye, a red ring surrounding a clear area with a red center. The size of the rash can range from dime-sized to the entire width of a persons back. Early Infection
  • EM Rash
  • Muscle and joint aches
  • Headache
  • Fever
  • Fatigue
Early Disseminated Infection
  • Multiple EM lesions
  • Facial paralysis (Bell's palsy)
  • Persistent headache, stiff neck
  • Diffuse numbness, tingling, burning
  • Intermittent joint pain and swelling
  • Impaired motor coordination
Late Infection
  • Painful inflammation of the joints, intermittent or chronic (arthritis)
  • Mild to moderate confusion
Less Common Symptoms of Late Lyme Disease
  • Heart abnormalities
  • Eye problems such as conjunctivitis
  • Chronic skin disorders
  • Limb weakness
  • Persistent motor coordination problems

Diagnosis

The diagnosis of Lyme disease is usually based on the presence of symptoms and the history of a tick bite. Most individuals with typical symptoms do not have Lyme Disease even if they have spent time outdoors. If you think you have the symptoms and believe you may have been exposed to a tick, see your doctor immediately. After four weeks, people with Lyme Disease usually have antibodies against B. burgdorferi in their blood. A blood test, called an ELISA, can test for the antibodies. When an ELISA is positive, the results should be confirmed with a second blood test called a Western blot. However, a negative test does not completely exclude the disease and a positive test alone does not confirm the diagnosis. Blood tests are used to support a diagnosis that is primarily based on symptoms and risk factors.

Treatment

Lyme Disease responds well to antibiotics. The antibiotics doxycycline, amoxicillin, and azithromycin are usually effective. (Note: Children and pregnant women should not take doxycycline.) You will need to take antibiotics for 10 days to four weeks, and some symptoms may continue after treatment. For persistent or severe cases that do not respond to oral antibiotics, intravenous (IV) antibiotic treatments (usually ceftriaxone) may be given until symptoms begin to decrease. The doctor will then prescribe oral antibiotics to be taken until you are symptom-free for several weeks.

Prevention

To help prevent Lyme Disease try the following:
  • Avoid areas that are likely to be infested with deer ticks—moist, shaded, wooded, or grassy areas. (Especially in northeastern, mid-Atlantic, and upper north-central regions of the U.S. and northwestern California)
  • Do the following when going to wooded grassy areas, especially in spring and summer:
    • Wear light-colored clothing with a tight weave to spot ticks easily.
    • Wear enclosed shoes.
    • Wear a long sleeve shirt and tuck it into your pants.
    • Tuck pants into socks or boot tops.
    • Wear a hat.
  • Apply insect repellent containing DEET to clothes and exposed skin. And follow the U.S. Environmental Protection Agency's guidelines for applying products with DEET. Insect repellents containing permethrin can be applied to pants, socks, and shoes.
  • Stay on cleared, well-traveled paths and walk in the center of trails to avoid overgrown grass and brush. Avoid sitting on the ground or stone walls.
  • Remove leaf litter, brush, and woodpiles from around the home and the edges of the yard.
  • Put clothes worn outdoors in the dryer for 20 minutes to kill unseen ticks.
  • Deer ticks are unlikely to infect unless they remain in contact with the skin for at least 24 hours. This leaves ample time to do a full-body check for ticks at the end of a day spent outdoors. Check pets as well. Not all ticks carry Lyme disease. Deer ticks are very small, approximately the size of a poppy seed.
  • If you do find a tick, remove it by doing the following:
    • Use a pair of tweezers to grasp the tick by the head or mouthparts as close to the skin as possible.
    • Pull directly outward, gently but firmly, with steady even force. Do not twist the tick out. Try not to crush the tick's body or handle it with bare fingers because this can spread infection.
    • Do not put a hot match to the tick or cover it with petroleum jelly, nail polish, or any other substance.
    • After the tick is removed, swab the site thoroughly with an antiseptic to prevent infection.
  • People aged 15-70 years old who spend frequent or prolonged time in tick-infested areas should consider taking the Lyme disease vaccine. It helps reduce your risk of infection but does not provide complete protection. Vaccinated persons should continue to practice protective measures.