Add to the list of potential negative side effects of global warming the spread of oyster herpes. Researchers have discovered a new strain of the virus that only manifests itself when water temperatures hit 61 degrees Farenheit, according to National Geographic.
The new strain, named Ostreid herpesvirus 1 (OsHV-1) μvar (mew-var), was first detected in 2008 among breeding Pacific oysters in France. Since then, the virus has wiped out 20 to 100 percent of oysters in the French beds, and this year it appears to have spread to the United Kingdom.
The reason for the emergence of herpes in oyster beds across Europe is a mystery, but many researchers see a correlation with global warming. The virus remains dormant when its hosts are in colder waters, so the disease is expected to spread as waters continue to warm worldwide.
OsHV-1 μvar is "more virulent than strains we identified before," said researcher Tristan Renault. Even worse, the virus attacks infected shellfish during breeding season, when oysters are more focused on producing eggs and sperm than on maintaining their immune systems. Renault added that the virus is so efficient at killing its hosts that it can wipe out 80 percent of the oysters in a bed within a week.
Since other known strains of herpes in oysters can infect a variety of different mollusks, there are concerns that the virus could also spread to populations of clams, scallops or mussels.
Concerned seafood lovers don't need to worry about catching herpes from an oyster shooter (the virus that infects mollusks is different than the one which infects humans), but the famed "food of love" is nevertheless rendered unsafe to eat when the animals are infected. That means the oyster fishing industry could be significantly harmed if the virus isn't contained.
The British government has promptly banned the shipping of oysters out of infected areas. But as waters continue to warm across Northern Europe, these efforts may prove futile. The virus has established itself among populations of wild Pacific oysters, and as global warming increases, so may their range.