Yaws is chronic contagious non-venereal disease caused by T. pertenue, usually beginning in early childhood. It resembles syphilis in its clinical course and is characterised by a primary skin lesion (mother yaw) followed by a generalised eruption and a late stage of destructive lesions of the skin and bone. Yaws is also known as pian, bubas or framboesia.

Yaws is crippling disease, lesions on palms and soles may disable a person for long periods making him dependent on others.
Persistent low levels of yaws is reported in Sri Lanka and India. Prior to the mass campaign of 1950`s , yaws was endemic in Andhra Pradesh, Madya Pradesh, Maharashtra, Orissa and Tamilnadu.

Last confirmed case detected in Gadchiroli district in the year 2000.