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Sea Bathers Eruption
I was swimming for exercise out in front of my hotel in Cozumel when my entire body started to tingle. I didn't see anything in the water, so I kept swimming. A few minutes later, I swam into a swarm of tiny pulsating brown blobs. They didn't have any tentacles that I could see. The stinging got pretty bad, especially underneath my bathing suit. I hosed off on the beach and jumped in the shower, and that seemed to help. Now I have an ugly red rash under my neck and where my bathing suit goes. I'm having trouble sleeping, and it seems like I'm tired all the time. What should I do?
Sea Bather's Eruption
Often misnamed "sea lice" (which are true crustacean parasites of fish, and which inflict miniscule bites), sea bather's eruption occurs in sea water and involves predominately bathing suit-covered areas of the skin, rather than exposed areas. The skin rash distribution is very similar to that from seaweed dermatitis, but no seaweed is found on the skin.
The cause is stings from the nematocysts (stinging cells) of the larval forms of certain anemones, such as Linuche unguiculata, and thimble jellyfishes. The injured person may notice a tingling sensation under the bathing suit (breasts, groin, cuffs of wetsuits) while still in the water, which is made much worse if he/she takes a freshwater rinse (shower) while still wearing the suit. The rash usually consists of red bumps, which may become dense and confluent (i.e., run together in a mass). Itching is severe and may become painful.
The Treatment
Treatment consists of immediate (for decontamination) application of vinegar or rubbing alcohol, followed by hydrocortisone lotion 1 percent twice a day. Topical calamine lotion with 1 percent menthol may be soothing.
If the reaction is severe, the injured person may suffer from headache, fever, chills, weakness, vomiting, itchy eyes and burning on urination, and should be treated with oral prednisone.
The stinging cells may remain in the bathing suit even after it dries, so once a person has sustained sea bather's eruption, the clothing should undergo machine washing or be thoroughly rinsed in alcohol or vinegar, then be washed by hand with soap and water.
For more information on dealing with marine life injuries, see the complete article by Paul S. Auerbach, M.D., M.S. on Marine Life Trauma from the Jan/Feb 1998 issue of Alert Diver.