While we predict that defence against infection should be energetically costly, the rate at which an individual uses and processes energy during infection has rarely been linked to the onset and severity of disease.

Infection outcomes are measured by both the virulence (severity of the effects) of the infection and the transmission of the pathogen.  The impacts of disease are known to vary between individuals, and most research on this issue has concentrated on the genetic variation in individuals to help understand these differences.

Collaborative research within the School of Biological Science at Monash University undertaken by the Hall research group and the Centre for Geometric Biology will investigate whether the exposure of a model organism (the water flea Daphnia magna) to a bacterial pathogen (Pasteuria ramosa) effects metabolic rates (a measure of energy use) and whether any measured changes in metabolic rates can, in turn, predict the outcomes of infection.

This well-studied system for infectious disease will enable researchers to measure infection success, the virulence of the infection (reduction in fecundity of Daphnia), the transmission potential (spore loads) and link these measures to metabolic rates in Daphnia at different ages.