1Pathology Unit, German Primate Center, Leipniz-Institute for Primate Research, 2Environmental Health Sciences, Columbia University Medical Center
Thursday 10:45-11:00, Ballroom A
Treponema pallidum is the bacterium that causes syphilis (subsp. pallidum), yaws (subsp. pertenue), and bejel (subsp. endemicum) in humans. Past serological surveys showed that infection is common in wild West African non-human primates (NHPs), but appeared rare or non-existent in East African and Asian/American NHPs. Clinical signs were described as mild lesions present on the muzzle, if they were present at all. Recently, using serological, histological, and molecular genetic techniques, we identified a strain of T. pallidum causing genital ulceration in olive baboons (Papio anubis) at Lake Manyara National Park in Tanzania. Using serology, we found that the infection was common at many other sites in Northern Tanzania but not in neighboring Kenya. In terms of genetic distance, the Tanzanian strains are most closely related to subsp. pertenue, although a phylogeny demonstrates that NHP strains are distinct from one another and, for the most part, fall outside of the clade of human T. pallidum strains. These data provide some evidence that baboon strains diverged prior to the divergence of the three human subspecies. In addition, the genetic variation among Tanzanian baboon strains suggests 1) sexual transmission evolved some time ago; 2) sexual transmission evolved multiple times; or 3) strain genetics are not the determining factor in mode of transmission. We will discuss the implications of our findings for understanding the evolution and pathogenicity of T. pallidum transmission in primates and conclude by outlining future research plans to characterize T. pallidum strains and the immunological response they provoke in NHP species.
The work was fundet by Robert Wood Johnson Foundation Health & Society Scholars program, NSF (Grant 0622399), the Wenner Gren Foundation, and the Howard Hughes Medical Institute Predoctoral Fellowship program, German Academic Exchange Program [grant no. D/06/43974]; the Christian Vogel Fond  and the World Association of Zoos and Aquariums [project no. 07002]. Molecular biological tests were partly fundet by Robert-Koch-Institute.