A hiker has a bull's-eye rash and then facial palsy. Which organism is the cause?

Answer and explanation

Correct answer: D. Borrelia burgdorferi

  1. Step 1: Erythema migrans and facial palsy occur in Lyme disease. Answer: Borrelia burgdorferi. Why not the others: Rocky Mountain spotted fever has a rash on wrists and ankles.

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