Isolation of Treponema DNA from Necrophagous Flies in a Natural Ecosystem

• Published in: EBioMedicine Vol. 11; no. C; pp. 85 - 90
• Main Authors: Knauf, Sascha, Raphael, Jane, Mitjà, Oriol, Lejora, Inyasi A.V., Chuma, Idrissa S., Batamuzi, Emmanuel K., Keyyu, Julius D., Fyumagwa, Robert, Lüert, Simone, Godornes, Charmie, Liu, Hsi, Schwarz, Christiane, Šmajs, David, Grange, Philippe, Zinner, Dietmar, Roos, Christian, Lukehart, Sheila A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2016; Elsevier
• Subjects: Advanced Basic Science; Africa; Animals; Diptera - classification; Diptera - microbiology; Dipteria; DNA, Bacterial; Ecosystem; Environmental Microbiology; Genes, Bacterial; Insect Vectors - microbiology; Internal Medicine; Nonhuman primates; Papio - microbiology; Phylogeny; Research Paper; Sequence Analysis, DNA; Tanzania; Transmission; Treponema - genetics; Treponema pallidum; Yaws; Dipteria; Yaws; Nonhuman primates; Transmission; Treponema pallidum
• ISSN: 2352-3964; 2352-3964
• DOI: 10.1016/j.ebiom.2016.07.033

Recently, the World Health Organization launched a campaign to eradicate the tropical disease yaws, caused by the bacterium Treponema pallidum subsp. pertenue; however, for decades researchers have questioned whether flies act as a vector for the pathogen that could facilitate transmission. A total of 207 fly specimens were trapped in areas of Africa in which T. pallidum-induced skin ulcerations are common in wild baboons; 88 flies from Tarangire National Park and 119 from Lake Manyara National Park in Tanzania were analyzed by PCR for the presence of T. pallidum DNA. We report that in the two study areas, T. pallidum DNA was found in 17–24% of wild-caught flies of the order Diptera. Treponemal DNA sequences obtained from many of the flies match sequences derived from nearby baboon T. pallidum strains, and one of the fly species with an especially high prevalence of T. pallidum DNA, Musca sorbens, has previously been shown to transmit yaws in an experimental setting. Our results raise the possibility that flies play a role in yaws transmission; further research is warranted, given how important understanding transmission is for the eradication of this disfiguring disease. •Treponema pallidum DNA was found in 17–24% of wild-caught flies in the Manyara region of Tanzania.•Results further support the possibility that flies play a role in yaws transmission.•New theoretic route of inter-species transmission for Treponema The discovery of Treponema pallidum DNA on necrophagous flies in Africa supports historical reports on possible transmission of the bacterium by flies as a mechanical vector. The bacterium (subsp. pertenue) causes human yaws, which is currently subject to eradication efforts. It has been shown that African nonhuman primates are also found to be infected with T. pallidum strains that are closely related to human yaws causing strains. The ecology of T. pallidum infection in primates is not yet fully understood and intra- and interspecies transmission pathways, apart from skin-to-skin contact in humans, are largely unknown.