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Ostreid herpesvirus 1 (OsHV-1) infections have been reported around the world and are associated with high mortalities of the Pacific oyster (Crassostrea gigas). In the summer 2008, abnormal mortality rates ranging from 80% to 100% were reported in France and affected only Pacific oysters. Analyses of oyster samples collected during mortality outbreaks demonstrated a significant detection of OsHV-1 (75% of analysed batches), which appeared stronger than previous years. DNA sequencing based on C and IA regions was carried out on 28 batches of OsHV-1 infected Pacific oysters collected in 2008. Polymorphisms were described in both the C and IA regions and characterized a genotype of OsHV-1 not already reported and termed OsHV-1 microVar. A microsatellite zone present in the C region showed several deletions. Additionally, 44 isolates collected in France and in the USA, from 1995 to 2007 were sequenced and compared to the 2008 sequences. The analyses of 76 sequences showed OsHV-1 microVar detection only in 2008 isolates. These data suggest that OsHV-1 microVar can be assumed as an emergent genotype.

Ostreid herpes virus 1 (OsHV-1) infections, notably reported in Europe and the USA, are closely associated with significant mortalities of the Pacific oyster, Crassostrea gigas, especially during its early stages of life. In summer 2006, we monitored mortality by strict daily verification of three full-sib families of oysters reared under common conditions. We quantified OsHV-1 using real-time PCR in dead and living individuals during and after a mortality event. Mortality events were severe and brief, but significantly different between tested families (cumulative mortality ranging from 1.2 to 49%). Real-time PCR assays revealed different viral DNA loads in dead individuals from different families (P < 0.001). Moreover, the mean level of infection among families was correlated with mortality (P < 0.05). Living oysters showed a significantly lower amount of viral DNA compared with dead ones. This is the first experiment showing the daily changes of individual OsHV-1 DNA load during a mortality outbreak. Our results also support the previously reported high genetic basis underlying the variance of resistance of Pacific oyster to summer mortality, suggesting that there might be a possibility to improve resistance to OsHV-1 by selective breeding.

Si pendant longtemps reflechir sur la place du corps dans la culture occidentale revenait a constater « sa place en tant que silence » a la difference de l'Orient ou de l'Extreme Orient, aujourd'hui force est de constater qu'il a toujours eu un role de vecteur social, psychologique, culturel et religieux. Il a toujours ete dans notre vie quotidienne un moyen de communication, d'echange par l'usage d'un certain nombre de signes, lies au langage, aux gestes, aux vetements, aux institutions, aux perceptions que nous avons de la realite. Ne negligeons pas non plus son importance dans les arts plastiques, dans le sport, dans les sciences, le rendant en fait omnipresent dans notre culture. Alors comment rendre compte de la multitude de facettes qu'il a eu au sein de notre histoire et ne pas montrer, contrairement a ce qu'ecrivait Leibnitz, « que tout ce qui se fait dans le corps de l'homme n'est pas aussi mecanique que ce qui se fait dans une montre ». Comment ne pas le limiter a quelques themes aussi reducteurs que celui de l'opposition classique matiere-esprit, eros-thanatos, bref, ne le definir que comme matiere a problemes ? Comment montrer que l'homme a toujours ete « le corps qui pense, le corps qu'il pense, le corps qu'il est, le corps qu'il a » ? Autrement dit comment montrer que le corps pouvait avoir une histoire autre que celle que l'histoire lui imposait.