Two skin lesions this week. Here's the first:
A farmer who works with sheep and goats presents with the lesion above. He notes fever, and exam shows regional lymphadenopathy. The lesion began as a red, solid, elevated papule then enlarged to the current state. Soon, it will form a red weeping surface, then develop a thin, dry crust with black dots covering the surface. After that, small papillomas will form. Finally, a thick crust grows over the lesion, the papillomas decrease in size, and the lesion flattens out.
Challenge: What's the cause of this disease?
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