U.S. Centers for Disease Control and Prevention – Emerging Infectious Diseases Journal Survey of Treponemal Infections in Free-Ranging and Captive Macaques, 1999–2012 Klegarth AR, Ezeonwu CA, Rompis A, Lee B, Aggimarangsee N, Chalise M, et al. Survey of Treponemal Infections in Free-Ranging and Captive Macaques, 1999–2012. Emerg Infect Dis. 2017;23(5):816-819. Abstract Survey results showed treponemal infection among pet macaques in Southeast Asia, a region with a high prevalence of human yaws. This finding, along with studies showing treponemal infection in nonhuman primates in Africa, should encourage a One Health approach to yaws eradication and surveillance activities, possibly including monitoring of nonhuman primates in yaws-endemic regions. Yaws, an endemic tropical disease distinguished by bone and skin lesions, is caused by infection with Treponema pallidum subsp. pertenue treponemes. Successful yaws treatment campaigns during 1950–1965 were followed by a resurgence of disease, and the World Health Organization (WHO) consequently mounted a yaws eradication campaign (1). Although the agent of yaws is spread among humans via direct contact, research has shown that nonhuman primates (NHPs) may serve as mammalian host reservoirs with the potential for zoonotic transmission (2). Successful eradication campaigns depend on there being no reservoir shielding the agent from eradication efforts; thus, the role that NHPs play in yaws among humans must be determined (3). African Old World primates (OWPs) can be infected by T. pallidum and exhibit symptoms of yaws (2). Of note, the Treponema Fribourg-Blanc strain (isolated from a baboon in western Africa in 1966) exhibits remarkable genetic similarity to strains that cause yaws in humans (4) and in experiments, was shown capable of infecting humans (5). More recently, studies focusing on treponemal infections among NHPs in eastern Africa and the Republic of Congo showed that the NHP geographic range overlaps considerably with areas having a formerly high prevalence of yaws in humans (2). Macaques (Macaca spp.), OWPs native to Asia and northern Africa, are susceptible to and have been experimentally infected with T. pallidum (6). After the initial WHO eradication efforts, yaws was believed to be largely eliminated from countries of mainland Asia, although reporting and active case detection have not been uniform throughout the region (7). Several island nations in Asia, however, continue to report active human yaws cases (8,9). Macaques, the most widely distributed and numerous NHPs in the world, are sympatric with humans throughout Asia, thriving in human-altered environments and commonly kept as pets. To further characterize the role NHPs might play in the maintenance of T. pallidum subspecies, we screened an extensive archive of serum samples collected from free-ranging and captive macaques