At any time during the year and in every ocean, swimmers and divers encounter jellyfish. They come in a variety of shapes and colors, from translucent to vibrant colors like pink, yellow, purple, and even luminescent. They range in size from penny-sized freshwater ones in west Michigan lakes, to giant-size pillow-top floating Portuguese-man-o’-war that can be found in a number of oceans around the world.
Jellyfish are primitive marine animals that have lived on earth more than 500 million years, having perfected a way to move and eat. They can float using the currents, or move under water pulsating up and down by sucking in water and forcing it out. Hanging from a flexible gelatinous head are numerous tentacles of various lengths with unique stinging cells at the ends. When the tentacles touch their prey, or humans, the stingers automatically fire paralyzing venom into the victim. Then the prey is brought underneath the head where the mouth devours it.
Jellyfish eat fish, shrimp and microscopic plants. In turn, sea turtles and sunfish eat them since they are immune to the venom.
Even dead on the beach, the stinging cells automatically fire, stinging beachcombers if the tentacles are touched. Different jellyfish venoms produce different pain levels in humans, but each requires immediate attention.
Jellyfish ‘blooms’ of concentrated numbers pose an even more dangerous situation, and the chances of being stung and hurt badly increase especially for divers and swimmers. At the beach, sometimes, an alert to these blooms is announced, but not all the time.
Jellyfish pose a worldwide health problem and a few types require antivenin, like Portuguese man-o’-war and the Australian Box jellyfish, which are life threatening. Old wives’ tales, misinformation on the internet, and information passed on by first-aid books treat jellyfish stings improperly.
In the past, vinegar, wet tobacco, ammonia, ice and even urine treated jellyfish stings. These methods are questionable.
New information coming from researchers at the University of Hawaii at Manoa, indicate the best treatment for all kinds of jellyfish stings is heat; hot water immersion or heat packs with temperatures of 113 – 130°F, break down the toxins. Further, heat is used for severe venomous marine stings or bites like those from stonefish or stingrays.
For jellyfish treatment, wash the area with seawater to release the tentacles and scrape the stinger off the skin with a credit card. Place a hot pack (or fill a hot water bottle with the hottest tap water) inside a thick towel and cover the area. Heat will denature the venom, while hydrocortisone cream and a bandage will protect it. Check the area often for blisters, tissue changes and increased heart rate. Give acetaminophen or ibuprofen for pain (never aspirin to children), unless the victim has been stung near the mouth or is having breathing problems (in this case go to the hospital). Continue with heat as necessary and seek medical attention if needed.
Helen Aitken is a freelance writer, with a science background. Her work has appeared in numerous magazines including Lakeland Boating, Southern Boating, Carolina Salt, and the Caribbean and South Florida editions of All At Sea.