In the past years in France, to mysterious mass die-off in oysters. Were affected in both free-living mussels, as well as the in-breeding farms. In part, killed all the oysters from the banks. Now researchers have solved the mystery of the mass extinction, as they report in the journal “Nature Communications”. Therefore, a double attack of the herpes virus and bacteria made the shells off.

The herpes virus OsHV-1, it is known that it can infest the food lover’s Pacific oysters (Crassostrea gigas). According to the research group led by Julien de Lorgeril, from the Université de Montpellier, the Virus has broken out in the past few years, however, the most frequently. Reason for this is mutations that made the Virus more aggressive. The herpes virus alone could not explain the mass die-off, however.

most of The oysters die happened within a few hours

The researchers have therefore examined in more detail, what with the infected animals. The result is that the herpes virus weakens the oysters so much that you can defend your immune system can hardly fight bacteria that invade the respiratory tract in the mussels. The bacteria can trigger, among other things, blood poisoning, and ensure that the oysters are rotting, quasi-alive, most of the animals die within a few hours.

The pathogens infect not only oysters in France, but worldwide. According to the researchers, for example, are broken in China, all the populations together, where 80 percent of the oysters are worldwide bred. Remedy for the herpes virus or bacteria there is, as yet, no.

The researchers hope, however, to get the pandemic under control. Because some of the oysters braved the herpes virus. You have, according to the researchers, certain genes that activate the immune system, as soon as the first virus in the shells. As a result, the majority of the surviving oysters of the infection. The researchers now want to build up the powerful the animals a new basic stock for breeding oysters.

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