Jellies!

My last blog was about INVISIBLE things that sting, but this one is all about much larger and visible stingers- JELLY FISH. We all know what they look like- bell-shaped, primitive looking soft tops, with variable amounts of tentacles streaming below. Swimmers typically stumble upon these creatures at or near the surface of the water, or washed up along the beach. Do NOT make the mistake of thinking an obviously dead jelly fish washed up on the shore is harmless! The stingers (nematocysts) in the tentacles will release their toxin and sting you- whether the jelly is dead or alive. 

Most jellyfish stings around the United States are an uncomfortable nuisance, but not life-threatening. The box jellyfish of Australia, however, can be lethal, and so these are a true medical emergency.

What happens with a jelly fish sting, and what should you do?

Stings cause immediate pain, redness and swelling. Severe stings can cause more bodily reactions, including, nausea, vomiting, headache, muscle aches, and fever/sweats/chills. Immediately wash the stung area in SALT WATER- stick it in the ocean. If you rinse with fresh water, remaining nematocysts will discharge, which means you will immediately have many more stings! If you have quick access to vinegar, pour that over the sting (because vinegar helps neutralize the toxin and prevents further release of more toxin.) Stings typically involve extremities, but if your eyes or mouth are involved with the sting, seek immediate medical attention. For the eyes, flush with a gallon of fresh water before heading for help. 

If the tentacles are stuck on you, pour vinegar over them, then make a paste with mud (or if available, with baking soda or shaving cream) before you try to remove the tentacles with tweezers or a knife/razor. Flush the area again with vinegar after removal. 

Topical steroid cream or ointment may help reduce discomfort and swelling after the initial first aid.

BOTTOM LINE: If you are going to swim in an area known to have jelly fish, make sure everyone knows not to touch "dead" jellies, and add a bottle of vinegar and a box of baking soda to your family beach bag.

Invisible Things that Sting...

The crystal clear waters beckon you, and you blissfully leap into the water ready to search for playful Honu (sea turtles) and brightly colored fish. Suddenly something stings your arm...and then your leg and your other arm. Are there jellyfish? No. In fact, you see absolutely nothing, yet SOMETHING or things are continuing to sting you. Have you baked your brain in the sun too long?

The picture above is from the Na' Pali coastline in Hawaii. While snorkeling there, a small group of the swimmers (including myself and one daughter) were bothered enough by invisible "stings" to get back on the boat. Meanwhile the majority of snorkelers were completely fine, despite swimming right next to other people who were being stung. Back on the boat, mosquito bite-looking lesions appeared everywhere we felt stings, with some people having a great deal of surrounding redness and swelling. The red bumps continued to sting like a moderate bee sting for ten minutes or so, then simply seemed to react like a mosquito bite- more itchy than painful. Our mystery stings lasted a few days, then disappeared.  

There are numerous names for rashes that crop up after swimming- sea bather's eruption, ocean itch, and my personal favorite, sea lice, to name a few. What causes these invisible stings?  Ultimately, some type of larval parasite burrows into a human instead of reaching its desired host (usually a water bird).  These larvae come from corals, sea anemones and thimble jellyfish. These parasites cannot live, grow or reproduce in human skin, so they die. Unfortunately, in many people, their presence sets off an allergic reaction- hence the red bumps and itch. With more intense allergic reactions, swimmers can develop headache, body aches, GI symptoms and fever. Primarily what is seen, however, are itchy red bumps or blisters.

The medical name for this type of rash is cercarial dermatitis. If the stings occur on exposed areas, there are typically fewer total red bumps. However, often sea bather's dermatitis shows up beneath where a swimsuit covered the skin, because the larva can get trapped in the fabric. Swimmers can have literally hundreds of bites covering their torso.

What can you do? If you start to feel bites, remove your suit BEFORE you shower- fresh water often triggers the larvae to sting. Vinegar may neutralize the toxin and reduce additional stings- apply to your body and rinse your swimsuit in the vinegar as well.

Additional treatment is targeted at the allergic reaction. Consider taking an oral antihistamine such as Benadryl, Claritin, Allegra or Zyrtec, and apply topical steroid cream or ointment on your torso or extremities (not on the face or genitals). Cool compresses may also help ease the itch or burn.

Is this rash contagious? Absolutely not- each bump is an allergic reaction to a larva burrowing into the skin, and the larva cannot be spread from one person's body to another. However, if you borrowed a wet swimsuit from a friend, any larva trapped in the suit material could certainly sting you.

BOTTOM LINE: Itchy, burning stings or bites after swimming is a frustrating allergic reaction, but only rarely medically "scary"- simply remove your suit as soon as possible, rinse with vinegar if available, take an oral antihistamine and/or use topical steroid cream on torso or extremity lesions and your symptoms should resolve within days to a couple weeks (depending on the severity.)