Lyme disease is an infection you can develop after a blacklegged tick carrying the Borrelia burgdorferi bacterium bites you.
Within days or weeks of the bite, you can experience symptoms like a rash, fever, chills, and other flu-like symptoms. When left untreated, Lyme disease can lead to facial paralysis, arthritis, irregular heartbeat, and nerve pain.
The early signs of Lyme disease can start to develop from three to 30 days after an infected tick bites you. If you have been bitten, look out for these symptoms.
About 70-80% of people with Lyme disease develop an erythema migrans rash, usually about a week after the bite.
An erythema migrans rash often resembles a bull’s eye—a small circle with a larger ring around it—but it may also appear as a discolored area of the skin. This discolored area can be darker or lighter than your natural skin tone.
The rash usually begins in the bitten area of the skin and expands over the following days. It can reach up to 12 inches in diameter. Erythema migrans rashes aren’t usually painful, swollen, or itchy, but they might feel warm.
Many people with Lyme disease also experience flu-like symptoms shortly after infection. These early symptoms, which can appear with or without an erythema migrans rash, may include:
- Muscle pain
- Joint pain
- Swollen lymph nodes
Lyme disease can usually be effectively treated with antibiotics. If left untreated, the infection can spread to other parts of your body, such as your nervous system, joints, and cardiovascular system.
Symptoms of untreated Lyme disease include:
- Shortness of breath
- New erythema migrans rashes
- Body aches
- Brain fog
Untreated Lyme disease can sometimes lead to severe or chronic health complications.
Neurologic Lyme Disease
If the infection spreads to your peripheral or central nervous systems, you may experience complications of neurologic Lyme disease.
Neurologic Lyme disease can cause meningitis, an inflammation of the brain and spinal cord. Meningitis can lead to symptoms like:
- Stiff neck
- Severe headache
- Vision problems
- Light sensitivity
Neurologic Lyme disease can also cause facial palsy, which is when the facial muscles become paralyzed, causing drooping on one or both sides of the face.
An inflammation of the nerves, or radiculoneuritis, is another complication of neurologic Lyme disease. This can lead to numbness, pain, or weakness in the arms or legs.
If the infection spreads to your joint tissues, it can cause Lyme arthritis, or inflammation in one or more joints. The affected joints will typically show obvious swelling, such as one knee appearing larger than the other. The joint may also feel warm and painful to move.
Lyme arthritis can develop about one to three months after the initial infection.
If the infection spreads to your heart, it can lead to Lyme carditis, which causes an interruption in the electrical signals involved in controlling the heartbeat. Symptoms include:
- Difficulty breathing
- Heart palpitations
- Chest pain
About 1% of people with Lyme disease develop this heart condition, usually about one to two months after they were bitten.
When to See a Healthcare Provider
Talk to a healthcare provider if you see the formation of what you think may be an erythema migrans rash or start feeling sick a few days or weeks after you suspect you may have been or know you were bitten by a tick.
Your healthcare provider can make a diagnosis of Lyme disease based on the results of a blood test, your potential for exposure to blacklegged ticks, and an assessment of your symptoms. If you test negative at first, your healthcare provider may recommend that you take another test in a few weeks. Most infections clear up with antibiotics over the course of two to four weeks.
A Quick Review
Lyme disease is a bacterial infection that you can contract after a bite from an infected blacklegged tick. Within a few days to a month of being bitten, most people with Lyme disease develop an erythema migrans rash that expands from the area around the bite. Other early symptoms of Lyme disease include muscle pain, fever, chills, and headache, which may appear even if you don’t develop a rash.
When left untreated, Lyme disease can lead to complications like arthritis, carditis (a heart condition), meningitis, nerve pain, and facial palsy. Some people also experience symptoms like cognitive issues, additional rashes, fatigue, and dizziness.
See a healthcare provider if you feel sick after being bitten by a tick.
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Centers for Disease Control and Prevention. Lyme carditis.
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Centers for Disease Control and Prevention. Lyme disease frequently asked questions (FAQs).