"Yaws, also known as framboesia, is a tropical disease produced by the Treponema pallidum subspecies pertenue."
"The first clinical sign of yaws is often a papilloma which can progress to an ulcer. The disease progresses through stages and can become latent 2. Untreated the disease affects skin, soft tissue and bone. In rare cases yaws can produce a disease called goundou, which disfigures the face due to tumour formation often with involvement of the facial bones 3."