This causes a chronic, slow-growing nodule or ulcer ("swimming pool granuloma"), lacking the acute evolution from papule to weeping nodule seen in Orf.
A deep fungal infection would typically have a slower, more indolent course, unlike the acute, self-resolving poxvirus infection of Orf.
A furuncle is a bacterial abscess, which is a tender, fluctuant, purulent nodule, whereas an Orf lesion is a firmer, weeping, non-purulent nodule.
A PG is a bright red, friable, vascular tumor that bleeds easily, while an Orf lesion is typically more violaceous and less friable.
A common wart has a dry, hyperkeratotic surface, unlike the exudative, "targetoid" nodule of Orf.
