The Consequences of Transmission Heterogeneities for Disease Outbreaks


There are ever-increasing concerns about the threat of emerging infectious diseases, in both wildlife (e.g., rabies, chytridiomycosis in amphibians, white nose syndrome in bats etc.) and humans (e.g., covid-19, Ebola, pandemic influenza, etc.). To understand, predict and manage these outbreaks requires a sophisticated understanding of the individual-level drivers of transmission.

Transmission is the fundamental process that drives the emergence and spread of new infectious diseases. It is typically conceptualised as a ‘mass action’ process, where homogenous groups of susceptible and infected individuals encounter each other at random. But, the reality is quite different; due to genetic, phenotypic, and environmental reasons, not all individuals are equally susceptible and not all infected individuals are equally infectious. Furthermore, individuals are likely to differ in their susceptibility and infectiousness for different pathogens. Quantifying these heterogeneities, and understanding their consequences for disease spread and control is vital if we are to develop effective disease mitigation strategies.

Using an invertebrate empirical system in both the lab and field, this studentship will:
1) Quantify host heterogeneities in susceptibility and infectiousness for a range of parasite species.
2) Partition those heterogeneities into environmental, genetic and demographic factors.
3) Develop theory to predict the consequences of different (non-random) mixing between these heterogeneous individuals for disease emergence and spread.
4) Experimentally test those predictions under a range of environmental scenarios.

This project will provide detailed insight into how heterogeneities in infectiousness and susceptibility influence the spread and impact of infectious diseases. This project will suit students with a good BSc (Upper 2:1 or 1st) and/or Masters in a relevant discipline, interested in fundamental and applied aspects of infectious disease ecology. They will be supervised in both theoretical (Fenton) and empirical (Viney) infectious disease biology, and will gain skills in experimental design, implementation and analysis, mathematical modelling and conceptual thinking.

Please contact the Principal Supervisor directly to discuss your application and the project - Prof A Fenton on


Open to students worldwide

Funding information

Self-funded project

The project is open to both European/UK and International students. It is UNFUNDED and applicants are encouraged to contact the Principal Supervisor directly to discuss their application and the project - Prof A Fenton on

Assistance will be given to those who are applying to international funding schemes.

The successful applicant will be expected to provide the funding for tuition fees and living expenses as well as research costs of up to £2500 per year.

A fee bursary may be available for well qualified and motivated applicants.

Details of costs can be found on the University website:
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Orlofske, S., Flaxman, S., Joseph, M., Fenton, A., Melbourne, B. & Johnson, P. 2017. Experimental investigation of alternative transmission functions: quantitative evidence for the importance of non-linear transmission dynamics in host-parasite systems. Journal of Animal Ecology 87, 703-715.

McCallum, H., Fenton, A., Hudson, P. J., Lee, B., Levick, B., Norman, R., Perkins, S. E., Viney, M., Wilson, A. J., Lello, J. 2017. Breaking beta: deconstructing the parasite transmission function. Philosophical Transactions of the Royal Society B 372, 20160084. doi: 10.1098/rstb.2016.0084.

Abolins, S., Lazarou, L., Weldon, L., Hughes, L., King, E.C., Drescher, P., Pocock, M.J.O., Hafalla, J.C.R., Riley, E.M. & Viney, M.E. (2018) The ecology of immune state in a wild mammal, Mus musculus domesticus. PLoS Biology, 16, e2003538.