Jellyfish stings Article by Doctor Kenneth Prudhoe Club de Mar Medical CentrePalma de Mallorca

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"DOCTOR AT SEA" a monthly Column in The Islander Magazine

Jelly Fish stings

Global warming appears to be invoked as the explanation for every environmental change but it does seem to be a good reason for the northward advance of jellyfish from tropical waters around Africa and into the Mediterranean. Ominously, sharks have also been reported off Mediterranean beaches. Mediterranean water temperatures have risen by about four degrees over the past few years partly due to repeated droughts which has led to reduced cool river water flowing into the sea and this, combined with coastal pollution and the over-fishing of natural predators such as tuna and turtles, has produced a fertile environment for jellyfish proliferation.

The Spanish Red Cross has reported a dramatic increase in the number of people treated in coastal resorts and notices are appearing in three languages warning bathers of the dangers of swimming and advising them where to seek treatment if they are stung. Last year more than 70,000 holidaymakers were treated for jellyfish stings in Spanish waters - 300 in one day near Malaga. The Spanish Environment Ministry has set up a vigilante network to detect banks of jellyfish and to predict their arrival on beaches – tons of them have been dredged up by clearance craft.

There are about three hundred types of jellyfish in the Med, including the notorious Portuguese Man of War whose stings can produce painful burns "like touching a hot stove" and can even lead to heart failure especially in more at risk groups such as the elderly, asthmatics and people with heart problems. Most of the recent attacks have been caused by Mauve Stingers whose poisonous sting can trigger shock. They grow up to four inches long and have eight tentacles each up to ten feet long.

A recent report in the Medical Journal of Australia advised removing the tentacles and rinsing the affected area with vinegar to produce a more acidic environment to reduce the release of more venom. Rinsing with sea water is helpful but fresh water is not recommended because the change in acidity between sea water and fresh water can stimulate further venom release. Similarly, it is not advisable to rub the area or to apply ice but the tentacles can be removed with tweezers or by applying shaving cream and scraping with a blunt instrument such as a credit card. The affected area may begin to itch after a day or so or may appear rather eczematous and some hydrocortisone cream can then be helpful. Occasionally the area can become infected and looks crusty or moist and then antibiotic treatment is indicated.

Sometimes a sting can cause a major allergic reaction (anaphylactic shock) which leads to severe breathing difficulty and a dramatic fall in blood pressure. This is life-threatening and requires immediate medical treatment. If it happens at sea then the on-board medical kit should provide adrenaline for urgent injection and oxygen to help with breathing.

Please email me (kenprudhoe@blueyonder.co.uk) if there are some topics you would like me to think about for future issues although I can’t promise to take up all of them!

Dr Ken Prudhoe, MCA Approved Doctor, can be contacted at Club de Mar Medical Centre, Palma de Mallorca. Tel: (+ 34) 639 949 125.