What is Lyme disease?
Lyme disease is a bacterial infection you get from the bite of an infected tick. At first, Lyme disease usually causes symptoms such as a rash, fever, headache, and fatigue. But if it is not treated early, the infection can spread to your joints, heart, and nervous system. Prompt treatment can help you recover quickly.
What causes Lyme disease?
Lyme disease is caused by bacteria. In the United States, this is usually a bacterium called Borrelia burgdorferi. It spreads to humans through the bite of an infected tick. The ticks that spread it are blacklegged ticks (or deer ticks). They are usually found in the:
- Upper Midwest
- Pacific coast, especially northern California
These ticks can attach to any part your body. But they are often found in hard-to-see areas such as your groin, armpits, and scalp. Usually the tick must be attached to you for 36 to 48 hours or more to spread the bacterium to you.
Who is at risk for Lyme disease?
Anyone can get a tick bite. But people who spend lots of time outdoors in wooded, grassy areas are at a higher risk. This includes campers, hikers, and people who work in gardens and parks.
Most tick bites happen in the summer months when ticks are most active and people spend more time outdoors. But you can get bitten in the warmer months of early fall, or even late winter if temperatures are unusually high. And if there is a mild winter, ticks may come out earlier than usual.
What are the symptoms of Lyme disease?
Early symptoms of Lyme disease start between 3 to 30 days after an infected tick bites you. The symptoms can include:
- A red rash called erythema migrans (EM). Most people with Lyme disease get this rash. It gets bigger over several days and may feel warm. It is usually not painful or itchy. As it starts to get better, parts of it may fade. Sometimes this makes the rash look like a "bull's-eye."
- Muscle and joint aches
- Swollen lymph nodes
If the infection is not treated, it can spread to your joints, heart, and nervous system. The symptoms may include:
- Severe headaches and neck stiffness
- Additional EM rashes on other areas of your body
- Facial palsy, which is a weakness in your facial muscles. It can cause drooping on one or both sides of your face.
- Arthritis with severe joint pain and swelling, especially in your knees and other large joints
- Pain that comes and goes in your tendons, muscles, joints, and bones
- Heart palpitations, which are feelings that your heart is skipping a beat, fluttering, pounding, or beating too hard or too fast
- An irregular heart beat (Lyme carditis)
- Episodes of dizziness or shortness of breath
- Inflammation of the brain and spinal cord
- Nerve pain
- Shooting pains, numbness, or tingling in the hands or feet
How is Lyme disease diagnosed?
To make a diagnosis, your health care provider will consider:
- Your symptoms
- How likely it is that you were exposed to infected blacklegged ticks
- The possibility that other illnesses may cause similar symptoms
- Results of any lab tests
Most Lyme disease tests check for antibodies made by the body in response to infection. These antibodies can take several weeks to develop. If you are tested right away, it may not show that you have Lyme disease, even if you have it. So you may need to have another test later.
What are the treatments for Lyme disease?
Lyme disease is treated with antibiotics. The earlier you are treated, the better; it gives you the best chance of fully recovering quickly.
After treatment, some patients may still have pain, fatigue, or difficulty thinking that lasts more than 6 months. This is called post-treatment Lyme disease syndrome (PTLDS). Researchers don't know why some people have PTLDS. There is no proven treatment for PTLDS; long-term antibiotics have not been shown to help. However, there are ways to help with the symptoms of PTLDS. If you have been treated for Lyme disease and still feel unwell, contact your health care provider about how to manage your symptoms. Most people do get better with time. But it can take several months before you feel all better.
Can Lyme disease be prevented?
To prevent Lyme disease, you should lower your risk of getting a tick bite:
- Avoid areas where ticks live, such as grassy, brushy, or wooded areas. If you are hiking, walk in the center of the trail to avoid brush and grass.
- Use an insect repellent with DEET
- Treat your clothing and gear with a repellant containing 0.5% permethrin
- Wear light-colored protective clothing, so you can easily see any ticks that get on you
- Wear a long-sleeve shirt and long pants. Also tuck your shirt into your pants and your pant legs into your socks.
- Check yourself, your children, and your pets daily for ticks. Carefully remove any ticks you find.
- Take a shower and wash and dry your clothes at high temperatures after being outdoors
Centers for Disease Control and Prevention
- Lyme Disease (American Academy of Family Physicians) Also in Spanish
- Lyme Disease (National Institute of Allergy and Infectious Diseases)
- Lyme Disease Frequently Asked Questions (FAQ) (Centers for Disease Control and Prevention) Also in Spanish
- Ticks and Lyme Disease: Symptoms, Treatment, and Prevention (Food and Drug Administration) - PDF Also in Spanish
Prevention and Risk Factors
- Stop Ticks to Avoid Lyme and Other Tickborne Diseases (Centers for Disease Control and Prevention) Also in Spanish
- Tick Removal: A Step-by-Step Guide (For Parents) (Nemours Foundation) Also in Spanish
- Travelers' Health: Mosquitoes, Ticks, and Other Arthropods (Centers for Disease Control and Prevention)
- Lyme disease: MedlinePlus Genetics (National Library of Medicine)
- Lyme Disease (VisualDX)
Health Check Tools
- Lyme Disease: Fact or Fiction? (Centers for Disease Control and Prevention)
Statistics and Research
- Lyme Disease Data (Centers for Disease Control and Prevention)
- Scientists Work Toward a Rapid Point-of-Care Diagnostic Test for Lyme Disease (National Institute of Allergy and Infectious Diseases)
- Tickborne Diseases Are Likely to Increase, Say NIAID Officials (National Institute of Allergy and Infectious Diseases)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Antibiotic prophylaxis for prevention against Lyme disease following tick bite: an...
- Article: Associating Land Cover Changes with Patterns of Incidences of Climate-Sensitive Infections:...
- Article: Lyme Disease Training and Knowledge Translation Resources Available to Canadian Healthcare...
- Lyme Disease -- see more articles