Sea Anemone Larvae Infects Jellyfish, Gives Humans Skin Rash

Posted on June 10, 2010

Mnemiopsis Leidyi Parasite


Researchers at the Department of Marine Ecology at the University of Gothenburg have been following the invasion of the American comb jellyfish, Mnemiopsis, for several years. They have discovered that the jellyfish contains larvae from a sea anemone that lives on it as a parasite. Researchers believe this parasite causes skin rashes on sea bathers in the United States.

The sea anemone, which the Gothenburg researchers believe to have identified through DNA analysis as Edwardsiella, is common in the comb jellyfish's natural environment in the West Atlantic, but has not previously been found in Swedish waters or anywhere else that the comb jellyfish has spread to. The sea anemone's larvae live as parasites on the jellyfish. The parasites cause skin irritation in humans when they come into contact with human skin. The researchers believe these parasites may become problematic for Swedish sea bathers too.

"The American variety of the sea anemone causes a skin complaint known as sea bather's eruption, which doesn't generally require treatment, but takes the form of quite a nasty rash that lasts for a few days," says researcher Erik Selander. "But the anemone we have found is confusingly similar to a Swedish anemone called Edwardsiella carnea, and we won't know which of the two species it is, or whether there actually are two species involved, until we have carried out further genetic analysis. If it is the American Edwardsiella that has come here, we could see isolated cases of sea bather's eruption here in Sweden too as we move towards autumn."

Mnemiopsis Leidyi Parasite infecting jellyfish


Photos: Erik Selander