September 26th, 2011
05:43 PM ET
Bloblike sea creatures, the jellyfish and the Portuguese man-of-war thwarted Diana Nyad’s attempt to swim from Cuba to Florida on Sunday.
After the swim, Nyad’s face appeared swollen and she had sting marks across her arm, where she had tussled with the various sea creatures. Nyad said their toxins began to cause partial paralysis and made it increasingly difficult for her to breathe and continue the swim.
Jellyfish don’t sting people in search of a meal, said Richard Satterlie, professor of marine biology at the Center for Marine Science at the University of North Carolina at Wilmington. They tend to sting anything or anyone they come into contact with.
Nyad’s team said she had no tools to ward off the jellyfish.
The jellyfish and man-of-war have tentacles dangling from a bell-shaped top. Depending on the species, the tentacles can dangle 10 to 30 feet away from their bodies. It’s easy for swimmers to get entangled with the creatures and stung multiple times – especially when swimming at night.
Each tentacle contains small stinging cells that act as darts called nematocysts.
“The stinging cells, nematocysts respond to pressure,” Satterlie said. “They fire much more easily, if there are chemicals or food. Mostly, if you brush against them, they’re going to fire.”
These creature’s tentacles are studded with nematocysts and if someone is sensitive to the toxins, he or she can go into anaphylactic shock.
Satterlie, who has been stung numerous times by the jellyfish he studies, said the stings leave behind welts.
“If you get entangled in tentacles, the number of stings is what’s important,” he said. “If you have a big piece of tentacle wrapped around your leg, that’s more pain, more toxins, more symptoms.”
Like the jellyfish, the man-of-war’s sting is painful, but not likely to be lethal. This creature moves as one unit, but is a colony. Its tentacles can reach as far as 165 feet, according to National Geographic.
People in the United States typically don’t go to hospitals for jellyfish or man-of-war attacks unless they are stung severely or have an allergic reaction.
Jellyfish stings tend to be more severe in Australia, where a particularly deadly type called the box jellyfish carry a lethal form of venom. Nyad received two stings from what her team identified as the potentially lethal box jellyfish.
Jellyfish are becoming bigger and more commonly spotted in the water. A study published in Science this month warned that jellyfish are turning into a great threat to the ocean ecosystem because it’s so effective in wiping out other prey.
The first thing to do after a jellyfish attack is to get out of the water and get the creature off your skin by scraping it off with a credit card or an object that is not your other hand.
“Studies have shown that immersion in hot water is somewhat effective in relieving the pain," said Dr. Robert Schwartz, professor and chairman of family medicine, University of Miami School of Medicine. "Some studies use vinegar.”
And no, don’t pee on yourself, because Satterlie said it’s gross and not likely to work.
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