Acute Lyme Disease
Recognize It Early. Treat It Fast.
What it is: Acute Lyme disease is the early stage of infection caused by the bacterium Borrelia burgdorferi, transmitted by the black-legged (deer) tick. This is the point when treatment is most effective. If addressed quickly, antibiotics usually cure the infection before it spreads to the heart, nervous system, or joints.
Delaying treatment can result in long-term health issues: arthritis, neurological damage, or life-threatening cardiac involvement. Early detection and antibiotics save lives.
Signs & Symptoms: Symptoms typically appear 3–30 days after a tick bite and may include:
Erythema migrans rash (EM): a red expanding rash, sometimes “bull’s-eye” shaped, though not always.
Flu-like illness: fever, chills, fatigue, headache, swollen lymph nodes, muscle and joint aches.
Eary complications: if untreated, the bacteria can move into the nervous system (causing meningitis or facial palsy) or the heart (causing Lyme carditis, with dangerous rhythm changes).
Seek emergency care if you develop fainting, palpitations, chest pain, severe headache, facial droop, or stiff neck.
Testing & Clinical diagnosis: If you have the EM rash, many doctors will treat you immediately without waiting for lab results.
Blood tests: Standard testing involves two steps — an antibody screening test (EIA) followed by a confirmatory test.
Limitations: Antibodies may not show up for the first 1–2 weeks after infection, so repeat testing may sometimes be needed.
Treatments:
Antibiotics (first line):
Doxycycline for 10–14 days (adults and older children).
Amoxicillin or cefuroxime axetil as alternatives.
Post-exposure prevention: A single dose of doxycycline within 72 hours of a high-risk bite can reduce the chance of infection.
Complications (like carditis): May require longer treatment (14–21 days) and sometimes hospitalization.
