| Titre : | Modeling the spread of avian influenza viruses in aquatic reservoirs: A novel hydrodynamic approach applied to the Rhône delta (southern France) (2017) |
| Auteurs : | Marion Vittecoq, Auteur ; Hermann Gauduin, Auteur ; Thibault Oudart, Auteur ; Olivier Bertrand, Auteur ; Benjamin Roche, Auteur ; Matthieu Guillemain, Auteur ; Olivier Boutron, Auteur |
| Type de document : | Article |
| Dans : | Science of The Total Environment (595 octobre 1, 2017) |
| Article en page(s) : | 787-800 |
| Langues: | Anglais |
| Mots-clés : | TdV |
| Mots-clés: | Avian influenza viruses ; Hydrodynamic model ; Wetlands ; Wild birds ; mallards |
| Résumé : |
Wild aquatic birds represent a natural reservoir of avian influenza viruses (AIV) that can be spread to poultry. AIV epizootics were associated with huge economic impacts during the last decades and are still of major concern. Within aquatic bird populations AIV are transmitted either by direct contact or through the ingestion of water that has been contaminated by infected individuals. This second route involving environmental transmission is of utmost importance in AIV dynamics, yet it has received far less attention than direct bird-to-bird contamination. Our objective was to combine a hydrodynamic model with data on mallard abundance and AIV infection rate within the population, so as to characterize virus dissemination within a complex wetland network. We chose the Vaccarès hydrosystem as a wetland model since it represents a large part of the Camargue region, which is a major wintering site for a large diversity of aquatic birds including AIV hosts. We aimed to identify the environmental parameters that drive AIV dynamics within this system and the spatio-temporal pattern of dispersion and persistence of viruses. Our results show that in a complex hydrosystem we can expect a great heterogeneity in AIV risk among wetlands. Our simulations underline how a simple “homogeneous box” approach could in the case of deltaic ecosystems minimize the expected risk by diluting it in the whole system. Moreover, such undermining of the risk perception could affect the predictions relative to risk duration. We present a new approach to identify hotspots of virus concentrations within deltaic areas that could take advantage of the duck count data, AIV surveys and hydrodynamic models that may already be available in several major duck wintering areas comprised of complex hydrosystems, such as the large European deltas. Our method could be of particular interest to optimize surveillance strategies in the current context of highly pathogenic AIV diffusion within wild bird populations. / Les auteurs ont modélisé le devenir des virus des grippes aviaires dans l’hydrosystème Vaccarès selon différents scénarios.Ils ont couplé les données hydrologiques du système avec celles dont nous disposons sur la présence des canards hôtes des virus Influenza A, agents des grippes aviaires, sur leur taux d’infection par ces virus et sur la persistance dans l’eau de ces derniers. Ils ont ensuite étudié comment se répartissaient les virus dans les différentes parties de l’hydrosystème Vaccarès en fonction de leur lieu et de leur date d’arrivée.
Il s’agit d’une première étape dans le développement d’un outil de modélisation des dynamiques des VIA dans l’eau en Camargue qui pourra à terme contribuer à optimiser la surveillance et à guider les prises de décision en cas de crise. |
| En ligne : | http://www.sciencedirect.com/science/article/pii/S0048969717306848 |



