Ecological approaches to informing public-health policy and risk assessments on emerging vector-borne zoonoses

Pathogens associated with vector-borne zoonoses occur in enzootic cycles within nature. They are driven by a combination of vertebrate host and invertebrate vector population dynamics, which in turn respond to changes in environmental stimuli. Human involvement in these cycles, and hence the occurrence of human disease, is often to act as incidental hosts. From a public health perspective our ability to better predict human outbreaks of these diseases and prepare intervention and mitigation strategies relies upon understanding the natural cycle of pathogen transmission. This requires consideration of for example, invertebrate and vertebrate ecology and biology, climatology, land use and habitat change. Collectively these can be referred to as medical entomology and medical ecology. This paper reviews the importance for inclusion of such disciplines when assessing the public health risk from vector-borne zoonoses and summarises the possible future challenges and driving forces for changes in vector status and vector-borne zoonoses emergence, with a particular focus on a UK and European context.