Authors

J Cohen¹; M Viney¹; A Fenton¹;  ¹ University of Liverpool, UK

Discussion

Theoretical models have repeatedly demonstrated that host heterogeneities in susceptibility and infectiousness can affect the dynamics of parasite spread. However these predictions have rarely been tested experimentally. Here I present results from a series of experiments using the red flour beetle (Tribolium castaneum) as the host, infected with Eugregarines, an apicomplexan gut parasite. We quantified heterogeneities in susceptibility and infectiousness in this system using six different colonies of beetles established from field-collected individuals trapped in distinct locations and at different times. We challenged larvae of each of the colonies with the same dose of parasite infective particles to assay host susceptibility, and assayed host infectiousness by quantifying the parasite infective particles produced by infected larvae. We show that the colonies differ in their susceptibility to the Eugregarines, but not in their infectiousness. We can then use different combinations of these colonies to vary population-level heterogeneity in free-running mesocosm experiments, allowing us to directly test model predictions about the consequences of host heterogeneities on parasite transmission.