Habitat disturbance and anthropogenic change are globally associated with extinctions and invasive species introductions. Less understood is the impact of environmental change on the parasites harbored by endangered, extinct, and introduced species. To improve our understanding of the impacts of anthropogenic disturbance on such host–parasite interactions, we investigated an invasive trypanosome (Trypanosoma lewisi). We screened 348 individual small mammals, representing 26 species, from both forested and non-forested habitats in rural Uganda. Using microscopy and PCR, we identified 18% of individuals (order Rodentia) as positive for trypanosomes. Further phylogenetic analyses revealed two trypanosomes circulating—T. lewisi and T. varani. T. lewisi was found in seven species both native and invasive, while T. varani was identified in only three native forest species. The lack of T. varani in non-forested habitats suggests that it is a natural parasite of forest-dwelling rodents. Our findings suggest that anthropogenic disturbance may lead to spillover of an invasive parasite (T. lewisi) from non-native to native species, and lead to local co-extinction of a native parasite (T. varani) and native forest-dwelling hosts.
Bibliographical noteFunding Information:
This research was supported in part by the Emory Global Health Institute, Emory University Environmental Science Department, and the appointment of J.S.S. to the Research Participation Program administered by Oak Ridge Institute for Science and Education (ORISE) through an Interagency Agreement with CDC. The authors thank the Uganda Wildlife Authority, Uganda National Council for Science and Technology, Makerere University Biological Field Station and local authorities for permission to conduct this study. The authors are thankful to J. de Roode for his encouragement and interests in investigating blood-borne pathogens. The authors thank S. Ockers, C. Akora, and I. Mwesige who provided valuable assistance in the field and K. Cross for assistance in the laboratory. The authors also thank S. L. Perkins, J. N. Mills, I. K. Damon, W. Stanley, U. Kitron, R. R. Lash, and S. P. Montgomery for helpful comments, logistical, and/or analytical assistance.
© 2016, International Association for Ecology and Health.
- Kibale National Park
- Trypanosoma lewisi
- Trypanosoma varani
- forest fragment
- small mammals