Lyme disease

Causative Agent

Borrelia burgdorferi, Borrelia mayonii

Type of Organism

Spirochete Bacterial Species

Length of Attachment for Transmission

18-24 hours

Initial Symptoms

• Some infected individuals will be asymptomatic.
• Symptoms can begin 3-30 days after exposure
• A rash resembling a bullseye may be present around the bite site. 20-30% of infected individuals will not experience this symptom.
• Flu-like symptoms are most common and include: Fever, chills, fatigue, headache, and muscle and joint aches.
• Vision changes, numbness and tingling may also occur.
• If infection is caused by Borrelia mayonii, nausea and vomiting are also common symptoms.

Diagnosis and Testing

Most often, clinical signs and a history of exposure will be the key to diagnosis. If Lyme is suspected, a 2-part test can be performed for confirmation.

1. EIA - Enzyme Immunoassay
2. Immunoblot/Western Blot

A positive result from the 1st test is required to run the second test and both must be positive to confirm disease.

CDC Treatment Recommendation

• Adults: Doxycycline 100mg- 2x daily, Cefuroxime axetil 500mg- 2x daily, or Amoxicillin 500mg- 3x daily for 10-21 days
• Children: Doxycycline 4mg/kg divided into 2 doses daily, Cefuroxime axetil 30mg/kg divided into 2 doses daily, or Amoxicillin 50mg/kg divided into 2 doses daily for 10-21 days

Disease Pathogenesis

• Early Lyme (Localized): Once inside the host, the disease will affect the skin near the site of attachment causing a bullseye rash in some patients.
• Early Lyme (Disseminated): Several weeks after exposure, the infection will spread throughout the body to the joints, eyes, heart and the nervous system. Other areas of the skin not associated with the site of attachment may also be infected resulting in a rash.
• Late Lyme (Disseminated): If bacteria become dormant in the infected areas from stage 2, they may reemerge weeks, months or possibly years after exposure. Disease progression can lead to arthritis of the joints, Lyme encephalopathy, or nervous system complications.