séminaire du pôle évolution du vivant

Parasite-parasite interactions and the effect of multiple infections on host's and pathogen's fitness - Godefroy Devevey, university of Edinburgh - vendredi 24 janvier 2014, 11h, amphi Monge




Host-parasite relationships are central in biology; they shape ecological interactions, evolutionary trajectories and affect many aspects of human development. Traditionally, the study of host-parasite interactions focused on one host and one parasite, omitting that most hosts are multiply infected. In this seminar, I want to stress the ubiquity of co-infection, and how the interactions between parasites modulate their own fitness and the effect they have on host life history traits. From empirical examples in rodents, I will illustrate different outcome of co-infections. For example, in the blood several species of bacteria of the genus Bartonella showed patterns of competition within a host, even though infection by one species facilitates infestation by a new species. Similarly, in hosts sequentially infected by several strains of the bacteria Borrelia burgdorferi, causative agent of Lyme disease, we observed a strong inhibitory priority effect, which seems independent of the host’s adaptive immune response. Finally, there are interactions even among parasites as different as a round worm and a protist; focusing only on the macroparasite, for example by treating with an antihelmintic, can have deadly consequences. We will conclude by an attempt to predict when parasites interact.

Dr Godefroy Devevey
Institute of Evolutionary Biology,
The university of Edinburgh
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