PhD project: Host diversity and disease risk in a fragmented landscape: evaluating the effects of habitat fragmentation on bat and viral communities in Brazil
Anthropogenic land-use change is a clear threat to global biodiversity and ecosystem services. It is also considered a key driver of emerging infectious diseases because it can result in novel contact among vectors, hosts and pathogens. While the impact of habitat fragmentation on biodiversity has been addressed, providing basic information on changing distributions and abundances of wildlife species, very little is known about the intrinsic relationships between host diversity and unknown pathogen diversity in wildlife, and how this influences the risk of cross-species transmission. The relationships between habitat fragmentation, host diversity and emerging infectious disease risk are likely to be complex and other mechanisms that can influence disease risk, such as human ecology (eg human activity, behaviour and occupancy), must also be considered. This study is investigating the effects of habitat fragmentation on the risks of zoonotic diseases spilling over from wildlife into human populations in a fragmented landscape in Pontal do Paranapanema, Brazil. Partnering with EcoHealth Alliance, the research focuses on three main questions:
- Does viral prevalence differ between bat communities in continuous forest, large and small forest fragments, and human settlements bordering the forest?
- Are ecological traits associated with viral prevalence?
- Do human–animal contact rates differ among different-sized forest fragments along a fragmentation gradient?
Elizabeth hypothesises that, for viruses with multiple host species, viral species richness and abundance may be relatively unaffected by habitat loss and fragmentation. In this scenario, if a multi-host virus is able to infect a broad range of hosts, their abundance and diversity may remain stable, or potentially increase if those host species that increase in abundance are more competent hosts (eg lower host dilution).
Elizabeth Loh is a member of the Durrell Institute of Conservation and Ecology.
International Development Research Centre (IDRC)
United States Agency for International Development (USAID)
- Loh E.H., Bogich T, Olival K.J., Johnson C, Mazet J, Karesh W.B., Daszak P. (2014) Targeting emergence pathways for zoonotic disease surveillance and control. Vector-borne and Zoonotic Diseases (in review).
- Loh E.H., Murray K.A., Zambrana-Torrelio C, Hosseini P, Karesh W.B., Daszak P. (2013) Ecological approaches to studying wildlife diseases. Microbiology Spectrum 1(3):OH-2009-2012.
- Karesh W.B., Dobson A, Lloyd-Smith J, Lubroth J, Dixon M, Bennett M, Aldrich S, Harrington T, Loh E.H., Machalaba C, Thomas M, Heymann D. (2012). The Ecology of Zoonoses: Their Natural and Unnatural Histories. The Lancet. 380: 1936-45.