Lyme Disease

Etiology

Lyme disease is an illness that is caused by a spirochete bacterium, Borrelia burgdorferi, which is transmitted to humans through the bite of infected ticks. Ixodes dammini, which is the deer tick, is located in the northwest and Midwest region of the united states, are commonly known to infect humans. They are found in grassy areas (including lawns), and in brushy, shrubby and woodland sites, even on warm winter days. They prefer areas where some moisture is present. The tick has three life stages: larva, nymph and adult. The nymphal stage appears to be responsible for most of Lyme disease cases. In the larval stage and the nymphal stage the ticks attach to a variety of small mammals, but prefer the white-tailed mouse, the main reservoir of Lyme disease. The adult tick prefers to feed on the white-tailed deer (hins the name deer tick). Each stage takes a single blood meal. They feed on a variety of warm-blooded animals including humans, dogs, cats, cows and horses. The entire life cycle requires three separate hosts and takes about two years to complete. The bite is painless so most victims don’t know they have been bitten.

Symptoms

In about 50% of the cases a characteristic rash or lesion called Erythema margins is seen. It begins a few hours to a few weeks after the bite of an infected tick. The rash generally looks like an expanded red ring. It is often described as looking like a bull’s eye with alternating light and dark rings. However, it can vary from a reddish blotchy appearance to red throughout. And it also can be confused with poison ivy, spider or insect bite of ringworm. At the same time that the rash develops, flu-like symptoms may occur with headache, sore throat, stiff neck, fever, muscle aches, fatigue and generally malaise. Some people develop the flu-like illness without getting a rash.

If ignored, the early symptoms may disappear but more serious problems can develop months to years later. The later symptoms of Lyme disease can be quite severe and chronic. Muscle pain, and arthritis, usually in the large joints, neurological symptoms include meningitis, numbness, tingling, and