It is early summer. A 40 year old Caucasian male in North Carolina presents with the rash seen above. He said for the past two days, he's had fever, severe headache, malaise, myalgias, arthralgias, and nausea. The rash started on his ankles and wrists and has proceeded to affect his other limbs and move centrally. He went fishing at a wooded lake a couple days ago. This is a life-threatening condition.
Challenge: What is the most likely diagnosis? What is the causative agent?
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