In a World Health Organization (WHO)–sponsored mass eradication campaign from 1952 to 1969, more than 160 million people in Africa, Asia, and South America were examined for treponemal infections, and more than 50 million cases, contacts, and persons with latent infections were treated. This campaign reduced the prevalence of active yaws from >20% to <1% in many areas. In recent decades, lack of focused surveillance and diversion of resources have resulted in documented resurgence of these infections in some regions. The most recent WHO global estimate (1995) suggested that there are 460,000 new cases per year (mostly yaws) and a prevalence of 2.5 million infected persons; during subsequent years, an increased incidence was documented in some countries. Recent areas of resurgent yaws morbidity include West Africa (Ivory Coast, Ghana, Togo, Benin), the Central African Republic, Nigeria, and rural Democratic Republic of the Congo. The prevalence of endemic syphilis is estimated to be >10% in some regions of northern Ghana, Mali, Niger, Burkina Faso, and Senegal. In Asia and the Pacific Islands, reports suggest active outbreaks of yaws in Indonesia, Papua New Guinea, the Solomon Islands, East Timor, Vanuatu, Laos, and Kampuchea. India actively renewed its focus on yaws control in 1996, achieved zero-case status in 2003, and declared elimination in 2006. In the Americas, foci of yaws are thought to persist in Haiti and other Caribbean islands, Peru, Colombia, Ecuador, Brazil, Guyana, and Surinam, although recent data are lacking. Pinta is limited to Central America and northern South America, where it is found rarely and only in very remote villages. Evidence of yaws-like and venereal diseases, with treponemal seroreactivity, in wild gorillas and baboons in Africa has led to speculation that there may be an animal reservoir for yaws.