This is an array of disease caused by parasites spread by the bite of small sandflies. In the West, "New World Leishmaniasis" is also called "chiclero ulcer" and "espundia", and in the Middle East the "Old World Leishmaniasis"it is called "Kala-azar" and "oriental sore".
Generally it starts with a slowly-expanding ulcer at the site of a bite - any such sore in someone who has spent time in an at-risk area needs to be examined by a knowledgeable physician. Below is a victim with several well-developed ulcerated lesions.
The ulcers will eventually heal, but further nodular skin lesions may develop, often causing severe disfiguring disease - in the Middle East these were called "Jericho Buttons":
This poor soul in South America developed severe disease: