écologie des virus influenza aviaires en Camargue - IRD

Chapitre IIIunder the artificial conditions of intensive poultry production and dispersal. Evolution of thishost­pathogen system, created by humans, may represent one of the main threats for humanhealth. Thanks to a growing number of studies focused on genetic characteristics of AIV, weare aware of the mechanistic basis of high pathogenesis. Our desire to predict and control ofAIV emergence through this complex host­pathogen system must, however, consider hostecology and ecosystem characteristics (natural or linked with human activities) in whichtheses viruses evolve.If the application of evolutionary theory to medical sciences allows a predictiveframework for long­term host­pathogen interactions, it also provides interesting possibilitiesfor the design of medical and public health protection measures [e.g. 62 ­ 63]. Integration ofecological and evolutionary theory in epidemiology and human diseases is of growinginterest [e.g. 64 ­ 65]. While they can provide useful information for long­term diseasemanagement, for AIV such approaches and their possible applications are unfortunatelycritically lacking. Do we have to favor developments of poorly diversified farming conditionswith high densities of genetically impoverished birds? What are the long­term effects ofmass vaccination? Can we avoid virus exchanges between wild and domestic birds? It is clearthat answering such key questions first requires sound understanding of natural mechanismsof virulence selection and, from that knowledge, takes account of ecological features thatmay select for HP AIV in artificial ecosystems.SummaryDetection of HP AIV in wild living birds is a rare event, suggesting that emergenceand persistence of such virulent forms in nature remain infrequent.132