écologie des virus influenza aviaires en Camargue - IRD

Émergence du virus H5N1 hautement pathogèneresponse to AIV infection, according to host life history traits.Should I kill my host?AIV infection in wild birds may also indirectly lead to host death via predation. In manyhost­pathogen associations, the pathology related to the infection leads to an overallweakening of infected individuals. Given that predators sometimes prey preferentially on sickindividuals, differential susceptibility between several host species (or individuals) can leadto greater predation on the more susceptible ones [48]. Recent studies reported clear effectsof LP AIV infection on food uptake and migratory competence [49], suggesting that hostbehavior may be affected by LP AIV viruses in subtle ways not previously envisaged. Suchphysiological or behavioral effects may decrease host anti­predator performance, favorpredation on infected birds and thus decrease AIV transmission among target hosts of thepathogen (but can lead to infections among predators and scavengers, as seen with Asiaticlineage HP AIV H5N1). Under this scenario, viruses that induce strong physiological effects,even if they do not directly lead to death, are unlikely to be selected in wild populations.Investigations on differential predation rates on AIV­infected wild bird species, consideringthe effects of the infection itself, but also differences in behaviour induced by infection, arecritically lacking.Pathogen distributions and abundances in the environment can alter the decisionshosts make with regard to whether to stay and resist or to disperse from one place to another[50]. Pathogen transmission and dispersal are intricately linked, and it is widelyacknowledged that pathogens may benefit from investing in dispersal strategies. AIVdispersal is poorly documented in natural conditions. Van Gils et al. [49] however recently129