NERC E4 The dynamics of infection, coinfection and transmission in a complex multi-host – multi-vector – multi-pathogen community

Interested individuals must follow the "how to apply" link on the Geosciences E4 Doctoral Training Partnership web page: http://www.ed.ac.uk/e4-dtp/how-to-apply

Summary
Zoonotic pathogens typically circulate in diverse wildlife communities comprising multiple host and vector species. This project will investigate how vector and pathogen specificity impact infection, coinfection, and transmission.

Project background
Understanding the dynamics of pathogen transmission within wildlife communities is vital for improving surveillance, and managing the risk, of potential pathogen spillover into humans or livestock. However, given their complexity, we have little understanding of pathogen transmission dynamics within multi-species ecological communities. These issues are particularly true for vector-borne pathogens (VBPs), which are responsible for many important infectious diseases in humans and livestock (e.g., malaria, dengue fever, sleeping sickness, Lyme disease), causing significant morbidity, mortality and economic loss. The epidemiology of VBPs is inevitably complex, involving interactions between at least three species: the pathogen, the vector and the definitive host. However, the communities in which VBPs circulate typically comprise many potential vector and host species, introducing substantial additional complexities. In particular, different vector species can vary considerably in their propensity to bite different hosts, and different host and vector species can vary considerably in their compatibility with different VBPs. Hence, the composition of the host and vector community, in terms of the abundance, compatibilities, and contact among the different host and vector species, plays a vital role in driving VBP transmission within the host community. Over the past 12 years, we have established a wild small mammal system that is commonly infected with a range of vectors (i.e. ticks, fleas) and a diverse community of vector-borne pathogens (i.e. Bartonella, Babesia, Borrelia, Anaplasma, Trypanosoma, etc.) and we have developed the appropriate tools to investigate the dynamics of infection and coinfection under natural conditions. The aim of this studentship is to use this complex natural system to investigate how specificity in both vectors and pathogens can impact the dynamics of infection, coinfection and transmission.

Research questions
How diverse is the vector-borne pathogen community in the multiple vector species found in the small mammal study system?
Does the diversity of the vector-borne pathogen community found in the vectors reflect the patterns of infection found in the multiple small mammal host species?
Does vector-borne pathogen coinfection within both vectors and hosts impact onward transmission and infection dynamics?
Can we use field experiments to test how pathogen and vector specificity impact infection and coinfection dynamics in this multi-host system?

Methodology
The programme of research will comprise an initial period (Year 1) of training in the necessary parasitological and molecular skills, as well as extensive fieldwork at a local study site (beginning in autumn of Year 1). The project will address some of the questions by conducting a field experiment to alter the prevalence and diversity of both vectors and vector-borne pathogens, to test how these perturbations impact infection, coinfection and transmission. In addition, the student will use an extensive field collection of vectors and associated small mammal samples and will use molecular diagnostics and sequencing to investigate vector-borne pathogen diversity and specificity, and explore how the dynamics of the pathogen community impact coinfection in both vectors and hosts.

Training
A comprehensive training programme will be provided comprising both specialist scientific training and generic transferable and professional skills. Training will be specifically provided in relevant immunological, parasitological, statistical and genetic techniques and the successful applicant will work with researchers with a breadth of expertise in ecology, immunology, evolutionary biology and host-pathogen interactions.

Requirements
The successful applicant will have a biological sciences degree, either a 1st or 2i, and possibly an MSc in ecology, evolutionary biology, zoology or infectious disease/parasitology or relevant experience.