Table 1.

Case studies of mechanisms connecting anthropogenic disturbance with biodiversity change and the subsequent effects on infectious disease spillover.

			Infectious disease case studies
Anthropogenic disturbance	Biodiversity change (type and direction)	Mechanisms of biodiversity change	Spillover layers affected	Disease impacts	No. in Figure 1	References
Agricultural expansion and intensification	Functional diversity (decreased)	Loss of large consumers increases rodent richness and abundance	Wildlife host density and distribution, and pathogen prevalence	Increased prevalence of Bartonella in rodents in Kenya	1	33
	Landscape diversity (decreased)	Resources become limited, pushing animals into human-modified landscapes	Wildlife host density and distribution, and pathogen prevalence; human exposure to pathogen	Increased prevalence and spillover (zoonotic transmission) of P. knowlesi in Borneo	2	63
Urbanization	Ecosystem phenological diversity (decreased)	Resources become limited, pushing migrating animals to form resident populations in human-modified landscapes	Wildlife host density and distribution, pathogen prevalence, and pathogen shedding; human exposure to pathogen	Increased prevalence, shedding, and spillover of Hendra virus	3	21
Climate change	Functional diversity (increased)	Polar species replaced by migrating nonpolar species (via predation and resource competition)	Wildlife host density and distribution; pathogen survival and spread; human exposure to pathogen	Increased spillover risk of rabies in Alaska as a polar reservoir of rabies (Arctic fox) is being replaced by a more human-landscape adaptable reservoir species (red fox)	4	120,125
	Taxonomic and interaction diversity (increased)	Drought and reduction in water resources lead to increased density and diversity of hosts around shared water resources	Wildlife host density and distribution	Increased spillover risk of E. coli in Botswana	5	130,131
Invasive species	Taxonomic, functional, and interaction diversity (decreased)	Introduction of Burmese python reduces abundance of large- and medium-sized mammals	Human exposure to pathogen	Increased spillover risk of Everglade virus in Florida as mosquito disease vectors feed on rodent reservoirs more frequently	6	136,137
Wildlife trade	Taxonomic, genetic, functional, interaction, and landscape diversity (decreased)	Removal of wild, mostly large-bodied animals (via hunting, trapping, transfer, killing) or overfishing directly reduces abundance and diversity of terrestrial and marine wildlife species	Wildlife host susceptibility to infection, and pathogen shedding; pathogen survival and spread; human exposure to pathogen	Increased spillover risk of Ebola in the Congo Basin as demand for wild meat from small-bodied mammals such as bats (Ebola reservoirs) increases (hunters and preparers of the bushmeat are exposed to bat bites, scratches, or blood)	7	169,171,173,174
Wildlife trade and urbanization	Taxonomic and interaction diversity (increased)	Wildlife markets aggregate novel assemblages of hosts, increasing host richness that is unique to markets and the food supply chain	Wildlife host density and distribution, susceptibility to infection, and pathogen shedding	Increased wildlife susceptibility to infection, reservoir density, pathogen shedding and spread of SARS viruses	8	162,166,167

Figure 1 illustrates the overall framework for linking anthropogenic disturbance to biodiversity change to disease spillover via the spillover layers being affected in each case study.