Flesh eating cod bug found off Norway

Atlantic cod are now among the species considered endangered

A new parasite which turns fish flesh into a slimy jelly has been found in cod off the Norwegian coast.

So far it does not appear to have affected the country’s cod farmers but the Institute of Marine Research and the industry are keeping a watch on the situation.

The parasite is known as Kudoa thyrsites. It is normally found in more southerly waters around Africa and South America , but it has now appeared around the coast of Helgeland.

Kudoa is a type of jellyfish, which attacks the cod through the skin and then gets into the muscles. After the fish dies, the parasite’s enzymes reduce the flesh to a liquified mass. The parasite is not infectious for humans.

The discovery was first unveiled by the Norwegian seafood news site Fiskeribladet but the national broadcaster NRK has now taken it to a wider public audience.

Norwegian Institute of Marine Research scientist Arne Levsen told NRK: “You can literally scrape off the meat with a spoon. The entire muscle structure dissolves. So there are very strong enzymes that are in flux.”

It was discovered off Norway quite by chance around the Helgeland coast in Nordland, normally a strongly cold water area.

Cod farms should be able to provide much greater protection, but the industry is closely monitoring developments at sea.

The parasite was discovered by chance in three out of 19 coastal cod, following a fishing boat trip off Helgeland. Closer examination under the microscope revealed Kudoa spores.

The discovery has surprised Institute researchers, who are now carrying out further research. Climate change, which brought serious jellyfish attacks last year, is one theory being looked at.

liquefied fish with ruler to give idea of scale

Mackerel infected with Kudoa jellyfish (photo Arne Levsen/Institute of Marine Research)


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