What should I know about jellyfish and Portuguese man o' war at Florida beaches?

The Portuguese man o' war is not a true jellyfish. The National Oceanic and Atmospheric Administration (NOAA) says it is a siphonophore, a colony of specialized individual animals called zooids. It has a gas-filled float on the surface that is see-through blue, pink or violet. Its tentacles average about 30 feet and can reach about 100 feet, and they break off easily. The Florida Department of Health says contact causes extreme pain and raised, whip-like red streaks, and serious exposure can cause breathing trouble, shock and even death, though NOAA says the sting is rarely deadly. A man o' war washed up on the sand may still sting even weeks later.

Other stinging jellyfish can cause red, raised, streaky welts that last 1 to 2 weeks, with pain, tingling, itching, nausea and headache. Broken-off tentacles sting too, and so do dead jellyfish on the beach, so do not touch them.

If you are stung, the Department of Health says to get out of the water, remove tentacles with tweezers or the edge of a credit card instead of bare fingers, and see the lifeguard. Do not use lemon juice, garlic, athlete's foot spray, head lice medicine, Epsom salts, bleach or gasoline. For treatment advice, call the Florida Poison Information Center Network at 1-800-222-1222. The call is free and confidential, you can call 24 hours a day, 7 days a week, and you talk to experts in poisoning; all local poison control centers in the United States use this number. Call 911 for trouble breathing, feeling faint or chest pain.

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