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International audience; The two main Zika virus (ZIKV) vectors, Aedes albopictus and Aedes aegypti (invasive and native species, respectively), are present in Gabon (Central Africa). The aim of this study was to determine the entomological ZIKV risk associated with these mosquito species in Gabon by evaluating their vector competence for an African (i.e. representative of the endemic strains circulating in sub-Saharan Africa) and two Asian (i.e. representatives of exogenous epidemic strains that could be introduced) ZIKV strains. The transmission efficiency of one Ae. aegypti and two Ae. albopictus field-collected populations from Libreville and Franceville was assayed at day 7, 14 and 21 after experimental oral infection. The two mosquito species could transmit all three ZIKV strains already at day 7 post-infection, but transmission efficiency was higher for the African strain than the non-African strains (>60% versus

Six partenaires le CIRAD, le CNRS, l'EID Méditerranée, l'INRA, l'IRD, l'UM (Université de Montpellier), collaborent autour des problématiques liées aux arthropodes vecteurs de pathogènes responsables de maladies infectieuses humaines ou animales et aux ravageurs de cultures. Vectopole Sud est un réseau unique en Europe, regroupant à Montpellier de très nombreuses compétences autour de ses problématiques avec un dispositif d'environ 400 agents dont plus de 110 cadres de recherche permanents. Les Unités Mixtes de Recherche (UMR) ASTRE, DGIMI, MIVEGEC, INTERTRYP et l'EID-Méditerranée intégrées à ce réseau mènent des activités de recherche et de formation se situant à de multiples interfaces entre biologie et santé, écologie et environnement, évolution et médecine. La démarche du réseau Vectopole Sud est d'associer santé publique humaine, vétérinaire et végétale en 'Une seule Santé' ('One Health'). A cette fin, Vectopole Sud regroupe 4 plateformes d'expérimentation, insectariums confinés et laboratoires associés, sur les arthropodes vecteurs et ravageurs, réparties sur 4 sites de l'agglomération Montpelliéraine : - La plateforme Vectopole du site de la Valette (Campus de l'IRD – UMR Mivegec, IRD/UM/CNRS), disposant de compétences en matière de recherche sur les vecteurs et les pathogènes d'importance médicale ; -la plateforme du site de Baillarguet (Campus du CIRAD – UMR ASTRE, CIRAD/INRA), disposant de compétences en matière de recherche sur les vecteurs et les pathogènes d'importance vétérinaire ; -la plateforme du site de Triolet (PIQ – Plateforme d'Insectes de Quarantaine, campus de l'UM – UMR DGIMI, UM/INRA), disposant de compétences en matière de recherche sur les insectes d'intérêt agronomique ; -la plateforme de l'EID Méditerranée, opérateur public de démoustication, développant des méthodes et outils de lutte innovants contre les moustiques nuisants et vecteurs potentiels de maladies infectieuses.

Background: Culicoides biting midges are hematophagous insects of veterinary importance able to transmit viruses such as bluetongue virus and Schmallenberg virus to livestock. The aim of this work was to describe the average temporal abundance of biting midges at a continental scale, by comparing the seasonal variation at six different latitude ranges from southern Spain to northern Sweden. Materials and methods: We gathered Culicoides obsoletus group trap data collected by national surveillance programs in nine European countries (Spain, France Germany, Switzerland, Austria, Denmark, Sweden, Norway, Poland) from 2007-2013. In total, 904 farms were sampled for Culicoides midges using UV light traps. We divided Europe into 6 latitudinal bands of 5° width and calculated the average weekly midge abundance as well as the average annual cumulative sum of biting midges for each of these bands. We plotted the results to visualize the spatial and temporal patterns at a continental scale. Results: The midge season began earlier in southern Europe (week 10) compared to northern latitudes (week 19). The season also lasted longer at southern latitudes and became progressively shorter towards the northern latitudes. Abundance peaks occurred during spring and summer at all six latitudinal ranges. Despite the steadily shorter vector season in the north of Europe, the annual cumulative sum of biting midges increased towards the north. Norway and Sweden with the shortest vector periods, had the highest number of the C. obsoletus group, reaching a cumulative sum of 455.000 midges on average annually, with some traps collecting more than 110.000 in one night. Discussion: Temperature drives the start and length of the midge season at different latitudes, but it does not seem to drive the increasing abundance towards the north. A possible explanation could be that midge abundance may be more related to breeding site availability and soil moisture than temperature. Conclusion: This is the first time quantitative seasonal abundances for biting midges have been aggregated and jointly analyzed for the whole of Western Europe. By ignoring the fine scale variation in abundance between farms and regions, we have isolated and quantified an overall south-north trend in the temporal abundance of biting midges. These results may facilitate decision making by e.g. the EU member states when objectives and joint decisions are needed for prevention and control of midge-borne infections on a continental scale.

Un réseau de surveillance entomologique (160 pièges) des populations de Culicoides a été en activité entre 2009 et 2012 en France continentale suite à la transmission du virus de la fièvre catarrhale ovine (FCO). Nous présentons ici la diversité et la dynamique des Culicoides sur l'ensemble du territoire en 2012 en regard des années précédentes. L'accent est mis sur les cartes de période d'inactivité vectorielle synthétisant les résultats 2009-2012.