While everyone is susceptible to tick bites, campers, hikers, and people who work on gardens and in other leafy outdoor venues are at the greatest risk of being bitten by them.
This is important because Lyme disease, an infection caused by the bacterium Borrelia burgdorferi, or B. burgdorferi, is transmitted via the bite of infected ticks.
Lyme disease is named after a town in Connecticut where, in 1975, it was first recognized. It is transmitted by a group of closely related species of ticks known as Ixodes.
Ticks in this group - deer ticks, western black-legged ticks, and black-legged ticks - are much smaller than the common dog or cattle ticks, and attach to any part of the body, often to moist or hairy areas such as the groin, armpits, and scalp.
The Centers for Disease Control and Prevention (CDC) reported 23,305 cases of Lyme disease in the United States in 2005. Most occurred in the coastal northeast, the Mid-Atlantic States, Wisconsin and Minnesota, and northern California.
The overwhelming majority of cases are reported in the summer months when ticks are most active and people spend more time outdoors.
The Food and Drug Administration regulates products that are used to help diagnose and treat this complex disease in humans. There are no licensed vaccines in the United States to aid in the prevention of Lyme disease in people.
Here's a look at what you need to know to protect yourself.
What are the Symptoms?
Lyme disease can cause fever, headaches, fatigue, and a characteristic skin rash called erythema migrans. Left untreated, infection can spread to joints, the heart, and the nervous system. Permanent damage to the joints or the nervous system can develop in patients with late Lyme disease. It is rarely, if ever, fatal.
Lyme disease has different stages.
Erythema migrans is a key early-stage symptom. This circular red patch usually appears at the bite site 3 to 30 days after the bite. It expands to 5 to 6 inches in diameter, and persists for 3 to 5 weeks. As the rash enlarges, it may take on a "bull's-eye" appearance. In some people this rash never forms, or it is not noticed.
Other symptoms of early Lyme disease
- muscle and joint aches
- chills and fever
- swollen lymph nodes
Symptoms that may not appear until weeks or months after a tick bite occurs
- arthritis (usually as pain and swelling in large joints, especially the knee)
- nervous system abnormalities
- heart-rhythm irregularities
What Precautions Can I take?
Educate yourself about Lyme disease, and try not to get bitten by ticks. More specifically:
- Avoid wooded, brushy, and grassy areas, especially in May, June, and July. (Contact the local health department or park/extension service for information on the prevalence of ticks in specific areas).
- Wear light-colored clothing so that you can see ticks that get
- Wear long pants and long-sleeved shirts.
- Wear shoes that cover the entire foot.
- Tuck pant legs into socks or shoes, and tuck shirts into pants.
- Wear a hat for extra protection.
- Spray insect repellent containing DEET on clothes and exposed skin other than the face, or treat clothes with permethrin, which kills ticks on contact.
- Walk in the center of trails to avoid brush and grass.
- Remove your clothing, and wash and dry them at high temperatures after being outdoors.
- Do a careful body check for ticks after outdoor activities.
There's a tick attached to me. What do I do?
Remove it! Using tweezers, grasp the tick close to the skin, pull straight back, and avoid crushing the tick's body. Save the tick for possible identification by a doctor or the local health department.