Yaws is a chronic infectious disease caused by the Treponema pallidum subspecies pertenue. It affects the skin, bone and cartilage; if left untreated, it can lead to deformities of the nose and bones of the leg. It has long been considered that yaws can be eradicated because humans are the only reservoir. The discovery in 2012 that a single, oral dose of the antibiotic azithromycin can completely cure yaws has reopened the prospects of yaws eradication.
In the Western Pacific Region, Papua New Guinea, Philippines, Solomon Islands and Vanuatu are currently known to be endemic.