What is Lyme Disease?
Lyme disease is a tick-transmitted bacterial disease caused by four main kinds of bacteria: Borrelia burgdorferi, Borrelia mayonii, Borrelia afzelii and Borrelia garinii. The first two types cause Lyme disease in the United States, while the second two are the leading causes in Europe and Asia. Lyme disease was first recognized in 1976 because of a large number of cases in Lyme, Connecticut. In the four decades since, it has become the most commonly reported tick-borne disease in the United States. More than 90% of cases occur in Maine, Virginia, Michigan, Minnesota, Wisconsin, Oregon and northern California, through no state is fully immune.
How is Lyme Disease Contracted?
Infected black-egged ticks, also called deer ticks, spread Lyme disease to humans through bites. Adult deer ticks are about the size of a sesame seed while younger ticks (nymphs) are about the size of a poppy seed. Because the nymphs are so tiny, they are difficult to see; adults are more easily discovered because of their larger size. After biting, deer ticks attach themselves to the skin and feed off the victim’s blood. Bites can occur on any part of the body but are most often found in moist or hairy areas, such as the scalp, armpits and groin. Ticks need to feed on their victims for 24 to 48 hours in order for Lyme disease to be transmitted.
Both nymphs and adult deer ticks can bite and attach themselves to people and transmit Lyme disease. Most bites are reported in summer when ticks are most active and more people are spending increased time outdoors. But they also can occur in early autumn, when the weather is still warm, as well as in late winter if the weather is unusually warm. A mild winter helps ticks to thrive and emerge in early spring to find their victims. Most people acquire Lyme disease through the bites of nymphs during the spring and summer months.
Spending time in wooded or grassy areas increase the risk of exposure to ticks. Even the edge area between lawns and woods can contain ticks. Ticks also can travel to lawns and gardens by hitching a ride on your pets who can then bring them into your house. People who spend a great deal of time outdoors—whether for leisure or for work—have a higher risk of exposure to ticks infected with the Lyme disease bacteria.
How Can You Minimize Chances of Contracting Lyme Disease?
It’s best to be proactive and take several precautions to limit your chance of being bitten by an infected tick. Avoid known tick-infested areas, especially in May, June and July. Some local health departments and park or extension services can provide information on the local tick distribution. Walk in the center of trails to limit contact with overgrown grass, brush and leaf litter. And don’t let your pets wander into tall grasses and weeds. Ticks perch on the tips of grasses, leaves and shrubs and crawl onto people and animals as they brush against them. Wearing a hat, long sleeves and pants and tucking your pants into your socks and your shirt into your pants can limit the exposure of your skin to ticks. Light-colored clothing can make the dark-colored ticks easier to spot if they do land on your clothes. Spray Environmental Protection Agency (EPA)-registered insect repellents containing DEET (diethyltoluamide) on exposed skin and clothing. Remove clothing after your time in the outdoors and wash and dry them at a high temperature. Shower or bathe as soon as possible after coming in from the outdoors. Perform daily tick checks even if you’ve only been outdoors for a short time.
Early removal of ticks can reduce the risk of Lyme disease as ticks must be attached to the skin for at least a day for the disease to take hold. If you do find a tick, remove it with fine-tipped tweezers. Grasp the tick as close to the skin’s surface as possible and then steadily pull upward with even pressure to remove the entire tick. Clean the bite area and your hands with soap and water, rubbing alcohol or an iodine scrub.
If you think or know you were bitten by a tick but are unsure if it was infected with Lyme disease, it’s best to contact your doctor so that you can be tested. Lab tests can identify the presence of antibodies that your body has produced in reaction to the Lyme bacteria. A two-stage testing process is used to assess possible Lyme disease infection. These blood tests are most reliable when they are done a few weeks after the tick bite because it takes that long for your body to produce measurable levels of Lyme disease antibodies. About 95% of people who have been infected for over a month develop antibodies to the Lyme disease bacteria. However, if antibiotics were taken, the antibodies may not be present.
The first test is the enzyme-linked immunosorbent assay (ELISA), which detects antibodies to Borrelia burgdorferi. However, it sometimes provides false-negative results during the early stages of Lyme disease. And it can also provide false-positive results. If the ELISA test is positive, a Western blot test, which detect antibodies to several proteins of Borrelia burgdorferi is performed to confirm the diagnosis. Sometimes, a sample of joint fluid or cerebrospinal fluid (the fluid that surrounds the brain and spinal cord) is obtained in order to detect genetic fragments of the Lyme disease bacteria. Both early and late-stage Lyme disease are treated with prescription antibiotics and both respond to these therapies. However, early treatment is best and more likely to prevent complications.
Symptoms That May Signal Lyme Disease
Lyme disease can be difficult to diagnose because some of its symptoms mimic those of other illnesses. For example, muscle aches, fatigue and fever can be mistaken for viral infections such as flu and infectious mononucleosis. Joint pain can be misdiagnosed as osteoarthritis, rheumatoid arthritis or juvenile rheumatoid arthritis. In addition, sometimes people don’t even realize that they’ve been bitten by a tick, particularly if the tick was in the tiny-sized nymph stage.
Despite these diagnosing difficulties, early diagnosis and treatment are essential to avoid the complications of untreated late stage Lyme disease. Left untreated, Lyme disease can lead to chronic joint inflammation (Lyme arthritis) particularly of the knees, cardiac irregularities (such as abnormal heart rhythm) and neurological problems (such as partial facial paralysis).
Below is a list of common Lyme disease symptoms. Keep in mind, not everyone will develop all of these symptoms, even if they are infected.
Early Stage Lyme Disease (about 3 to 30 days post-tick bite)
- Erythema Migrans Rash:
- About 70% to 80% of infected people will develop the EM (erythema migrans) rash, which is characteristic of Lyme disease. The EM rash is a red circle that usually appears at the tick bite site, about 3 to 14 days after the bite. Most of the time it slowly increases in size, often with a clear site in the middle that makes the rash look like a bull’s eye. It usually disappears in about 3 to 4 weeks.
- Enlarged spleen
- Swollen lymph nodes
- Painful, swollen joints
- Stiff neck
- Muscle aches
- Sore throat
Late Stage Lyme Disease (days to months post-tick bite)
As the disease progresses, the symptoms experienced often change, causing impacted individuals to experience a combination of the conditions below:
- Heart palpitations or irregular heart beat (Lyme carditis)
- Facial palsy (loss of muscle tone on one or both sides of the face)
- Impaired short-term memory
- Nerve pain
- Shortness of breath
- Bouts of muscular, tendon or bone pain
- Shooting pains, tingling or numbness in hands or feet
- Arthritis (brief bouts of pain and swelling, particularly in the knee)
- Additional EM rashes