Lyme Disease
A bacterial infection transmitted by infected blacklegged ticks that can affect the skin, joints, nervous system, and heart.
What causes Lyme Disease?
In the United States, Lyme disease is caused mainly by Borrelia burgdorferi and rarely Borrelia mayonii. It spreads through bites from infected Ixodes blacklegged ticks.
Symptoms and what to notice
Early illness may cause an expanding erythema migrans rash, fever, chills, headache, fatigue, muscle or joint aches, and swollen lymph nodes. Later disease can cause facial palsy, meningitis, nerve pain, arthritis, or abnormal heart rhythm.
How long can it last?
Early symptoms can begin 3 to 30 days after a tick bite. Appropriate antibiotic treatment commonly lasts 10 days to 4 weeks depending on the manifestation. Some people have prolonged fatigue, pain, or cognitive symptoms after treatment.
How serious is Lyme Disease?
Untreated infection can spread to the nervous system, heart, or joints. Lyme carditis can cause dangerous conduction block; neurological disease can cause meningitis or facial palsy; recurrent or persistent arthritis can occur.
Treatment and management
Most cases are treated successfully with doxycycline, amoxicillin, or cefuroxime axetil. Drug and duration depend on symptoms, age, pregnancy, allergies, and disease stage. Selected severe neurological or cardiac cases require intravenous ceftriaxone and hospital monitoring.
Vaccine: who and when?
No human Lyme disease vaccine is licensed or available in the United States as of September 2026. Vaccine candidates are in clinical development. Tick-bite prevention, prompt tick removal, and selected single-dose doxycycline prophylaxis after a high-risk bite are the current preventive tools.
Cost note: No vaccine price applies. Testing, treatment, and tick-removal or preventive-care costs vary by provider, insurance, and clinical circumstances.
Trusted source
Patient cost varies by insurance, provider, location, and eligibility. Coverage and public-health access differ, so listed prices are examples rather than guaranteed patient prices. This page is for general education and does not replace individualized medical advice, diagnosis, vaccination assessment, or treatment.
Lyme Disease: Symptoms, Causes, Treatment, Prevention, and Vaccine Information
Lyme disease is the most commonly reported vector-borne disease in the United States. Risk is highest in parts of the Northeast, mid-Atlantic, upper Midwest, and Pacific Coast where infected Ixodes ticks occur. Nymphal ticks are tiny and active during warmer months, so a person may never notice the bite. Early recognition and correct antibiotics usually produce rapid, complete recovery.
Important: This page is for general education. It does not replace diagnosis, treatment, vaccination advice, or emergency care from a qualified healthcare professional.
Quick Facts
| Topic | Current information |
|---|---|
| Cause | In the United States, Lyme disease is caused mainly by Borrelia burgdorferi and rarely Borrelia mayonii. It spreads through bites from infected Ixodes blacklegged ticks. |
| Main symptoms | Early illness may cause an expanding erythema migrans rash, fever, chills, headache, fatigue, muscle or joint aches, and swollen lymph nodes. Later disease can cause facial palsy, meningitis, nerve pain, arthritis, or abnormal heart rhythm. |
| Typical course | Early symptoms can begin 3 to 30 days after a tick bite. Appropriate antibiotic treatment commonly lasts 10 days to 4 weeks depending on the manifestation. Some people have prolonged fatigue, pain, or cognitive symptoms after treatment. |
| Treatment | Most cases are treated successfully with doxycycline, amoxicillin, or cefuroxime axetil. Drug and duration depend on symptoms, age, pregnancy, allergies, and disease stage. Selected severe neurological or cardiac cases require intravenous ceftriaxone and hospital monitoring. |
| Vaccine status | No human Lyme disease vaccine is licensed or available in the United States as of September 2026. Vaccine candidates are in clinical development. Tick-bite prevention, prompt tick removal, and selected single-dose doxycycline prophylaxis after a high-risk bite are the current preventive tools. |
History and Public-Health Importance
A cluster of children with arthritis near Lyme, Connecticut, in the 1970s led investigators to recognize the syndrome. Willy Burgdorfer later identified the spirochete carried by blacklegged ticks. Surveillance, two-tier antibody testing, and treatment guidelines followed. A previous human vaccine was withdrawn from the U.S. market in 2002; new candidates are being studied but none is licensed as of September 2026.
What Causes Lyme Disease?
In the United States, Lyme disease is caused mainly by Borrelia burgdorferi and rarely Borrelia mayonii. It spreads through bites from infected Ixodes blacklegged ticks.
Ticks acquire Borrelia from infected wildlife and transmit it while feeding. In most cases, an infected tick must be attached for more than 24 hours and often 36 to 48 hours before transmission becomes likely, so prompt removal is protective. Lyme disease does not spread through casual contact, kissing, sex, food, water, air, or mosquito bites. Pets can bring ticks indoors but do not directly transmit Lyme disease to people.
Symptoms and Typical Course
Early illness may cause an expanding erythema migrans rash, fever, chills, headache, fatigue, muscle or joint aches, and swollen lymph nodes. Later disease can cause facial palsy, meningitis, nerve pain, arthritis, or abnormal heart rhythm.
Erythema migrans expands gradually and may be uniformly red, target-like, warm, or painless; it is not always a textbook bull’s-eye. Early disseminated infection may cause multiple rashes, facial palsy, meningitis, shooting pain, or carditis. Months later, untreated disease may cause episodes of swelling in large joints, especially the knee. Symptoms after treatment require careful evaluation rather than automatically assuming active infection.
Complications and Who Is at Higher Risk
Untreated infection can spread to the nervous system, heart, or joints. Lyme carditis can cause dangerous conduction block; neurological disease can cause meningitis or facial palsy; recurrent or persistent arthritis can occur.
Lyme carditis can cause dizziness, fainting, shortness of breath, chest pain, or dangerous atrioventricular block. Neurological disease can cause facial weakness, severe headache, stiff neck, radicular pain, numbness, or weakness. Arthritis can produce marked swelling. A minority of treated patients experience prolonged fatigue, pain, or cognitive difficulty known as post-treatment Lyme disease syndrome; prolonged antibiotics have not been shown to improve this syndrome and can cause serious harm.
How It Is Diagnosed
An erythema migrans rash in a person with plausible exposure can be diagnosed clinically without waiting for blood tests. Otherwise, CDC recommends FDA-cleared two-step antibody testing. Tests may be negative during the first weeks before antibodies develop and can remain positive for years after infection, so they do not prove ongoing disease or cure. Testing ticks is not recommended to guide treatment.
Treatment and Recovery
Most cases are treated successfully with doxycycline, amoxicillin, or cefuroxime axetil. Drug and duration depend on symptoms, age, pregnancy, allergies, and disease stage. Selected severe neurological or cardiac cases require intravenous ceftriaxone and hospital monitoring.
Early skin disease is treated with an oral antibiotic, commonly doxycycline, amoxicillin, or cefuroxime. Courses vary by manifestation, usually from 10 days to four weeks. Facial palsy, meningitis, carditis, or arthritis requires syndrome-specific care; severe heart block or neurological disease may need intravenous ceftriaxone and hospitalization. Most people improve completely when treated early.
Vaccine Information
No human Lyme disease vaccine is licensed or available in the United States as of September 2026. Vaccine candidates are in clinical development. Tick-bite prevention, prompt tick removal, and selected single-dose doxycycline prophylaxis after a high-risk bite are the current preventive tools.
No licensed human vaccine is available. A canine Lyme vaccine does not protect people and must never be used in humans. After a clearly high-risk Ixodes bite, a clinician may prescribe one doxycycline dose when the tick is identified, likely attached at least 36 hours, removed within 72 hours, exposure occurred in a high-incidence area, and the medicine is safe for the patient.
Prevention
Use EPA-registered repellent, wear long clothing, treat gear with permethrin, walk in the center of trails, and check the body after outdoor activity. Shower soon after coming indoors and tumble-dry clothing on high heat. Remove an attached tick with fine-tipped tweezers by pulling steadily upward, then clean the site. Record the date and monitor for symptoms.
When to Seek Medical Care
Seek prompt care for an expanding rash, facial weakness, severe headache, a swollen joint, fever after a tick bite, or new neurological symptoms. Emergency evaluation is needed for fainting, chest pain, breathing difficulty, or palpitations that could represent Lyme carditis.
Frequently Asked Questions
Does every Lyme rash look like a bull’s-eye?
No. Many erythema migrans rashes are uniformly red or differently shaped. The key feature is gradual expansion.
Can Lyme disease spread between people?
No evidence supports ordinary person-to-person, sexual, food, water, or airborne spread.
Should a removed tick be tested?
CDC does not recommend using tick test results to decide treatment because they do not reliably predict human infection.
Is a human Lyme vaccine available?
No licensed human vaccine is available in the United States as of September 2026, though candidates remain in development.
Key Takeaway
Preventing tick attachment, removing ticks promptly, recognizing an expanding rash, and using the correct short antibiotic course are the most effective ways to avoid Lyme complications.
Medical, treatment, and vaccine information was reviewed against official U.S. public-health guidance available through September 2026.