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"Sex-Crazed" Oysters Are Getting Herpes And It’s Killing Them

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If you love seafood, and oysters in particular, you'll be alarmed to know that a recent report has found a deadly virus that is spreading rapidly and threatening Pacific oysters (Crassostrea gigas).

Oysters eat tiny plankton that they filter from the surrounding water. A single oyster will process up to 50 gallons of water in a day, thus improving water quality and making their ecosystems healthier.

Unfortunately, the water they grow in can be filled with disease-causing microorganisms that affect both oysters and humans....

Pacific oysters, the world’s most popular and valuable oyster species, are being affected by a deadly herpes virus.

Ostreid herpesvirus 1 (OsHV-1), is threatening Pacific oysters and it is almost guaranteed to spread more widely thanks to globalization.

While it can affect other species of clams and muscles, the OsHV-1 is genetically distinct from other animal herpes viruses - meaning that it will not infect humans.

Pacific oysters used to be pretty resistant to infectious diseases until this strain of oyster herpes emerged in the early 1990s.

This strain of herpes affecting oysters behaves the same way as the human strain. When a human is infected with herpes, they sometimes get cold sores.

Normally, the virus is present at such a low level that it doesn't cause cold sores. But, after a stressful situation, the virus replicates and cold sores appear.

Since not all oysters die of herpes, it's likely that the virus levels remain low within infected oysters' tissues.

A stressful event, such as the water temperatures rising during the summer, will cause the virus to reactivate and spread.

The Smithsonian reports that mass oyster deaths occur each year during the summer and that a microvariant of the herpes virus was first detected in France in 2008. It killed between 80% and 100% of all affected oyster beds.

In 2010, an oubreak in England killed more than eight million oysters.

Colleen Burge, Assistant Professor at the Institute of Marine and Environmental Technology at the University of Maryland believes it is only a matter of time before the virus reaches oyster colonies in the U.S.

"It may only be a matter of time until they reach U.S. coastal bays or other non-impacted oyster growing areas. Oysters can’t move themselves out of harm’s way, nor can we move all susceptible oysters, so we need to protect them where they grow."

[h/t Smithsonian / National Geographic]