Introduction
Background
Seabather's eruption was first described in 1949 as a pruritic papular eruption occurring in bathers off the eastern coast of Florida. Seabather's eruption is a highly pruritic, papular eruption that occurs underneath the swimsuit after extended exposure to seawater. Seabather's eruption results from a hypersensitivity to the larval form of the thimble jellyfish, Linuche unguiculata.1 Most cases occur from March to August, but the incidence peaks in May and June.
A related eMedicine article is Cutaneous Manifestations Following Exposures to Marine Life. Additionally, the Medscape CME course Climate Change and Public Health may be of interest.
Pathophysiology
Seabather's eruption is a cutaneous hypersensitivity reaction to the larval form (planulae) of the thimble jellyfish, L unguiculata. The eruption typically occurs underneath the bathing garments, which are believed to trap the jellyfish larvae against the skin. Whether the discharge of venom by the trapped larvae plays an important role in the pathogenesis of the eruption remains uncertain. Factors that promote the discharge of venom by the larvae include wearing of bathing suits for prolonged periods following swimming, exposure to fresh water through showering, and mechanical stimulation.
Frequency
United States
The incidence of seabather's eruption is seasonal; the highest incidence occurs from May through August. This coincides with the warm gulf streams running along the Atlantic coastline of Florida and the corresponding spawn of thimble jellyfish larvae, which results in the high seasonal concentration of Linuche planulae. In 1997, Kumar et al2 reported the occurrence of seabather's eruption in Palm Beach saltwater swimmers in May to be 16%.
International
Seabather's eruption has been reported in Mexico and the Caribbean. The true prevalence of seabather's eruption along international coastlines remains unknown.
Mortality/Morbidity
No deaths have been attributed to exposure to thimble jellyfish larvae.
Race
Seabather's eruption occurs independent of race.
Sex
Seabather's eruption has been noted with equal frequency in both sexes.
Age
No correlation between age and risk for developing seabather's eruption has been noted. The severity of symptoms, particularly the frequency of fever, is greater in children than in adults.
Clinical
History
The eruption begins a few hours after bathing in the ocean.
- Pruritus is the most common symptom in patients with seabather's eruption (98%). It typically lasts 1-2 weeks.
- Fever and malaise are the next most commonly observed symptoms (23%). Fever is observed in 18% of patients. However, 40% of patients younger than 16 years report fever compared with 10% of adults.
- Systemic symptoms, including fever, nausea, abdominal pain, and diarrhea, are more common in children than in adults.
Physical
On physical examination, patients with seabather's eruption typically display inflammatory papules in a distribution pattern that mimics the bathing suit. Lesions have been noted to occur in the axillae; in men with significant chest hair, they occur on the chest.
- Relatively rare signs and symptoms of seabather's eruption include the following:
- Nausea
- Headache
- Sore throat
- Cough
- Diarrhea
- Abdominal pain
Causes
Seabather's eruption is caused by exposure to the larval form (planulae) of the thimble jellyfish, L unguiculata.
- The seasonal variation in the concentrations of thimble jellyfish larvae in endemic areas lead to the increased incidence of seabather's eruption from May through August, with a peak in May and June.
- Freudenthal and Joseph3 reported the larvae of the sea anemone Edwardsiella lineata as the cause of an outbreak of seabather's eruption on Long Island, New York. This organism also has nematocysts. Various species of Cnidaria larvae in other waters can likely produce similar eruptions.
More on Seabather's Eruption |
 Overview: Seabather's Eruption |
| Differential Diagnoses & Workup: Seabather's Eruption |
| Treatment & Medication: Seabather's Eruption |
| Follow-up: Seabather's Eruption |
| References |
| Next Page » |
References
Segura Puertas L, Burnett JW, Heimer de la Cotera E. The medusa stage of the coronate scyphomedusa Linuche unguiculata ('thimble jellyfish') can cause seabather's eruption. Dermatology. 1999;198(2):171-2. [Medline].
Kumar S, Hlady WG, Malecki JM. Risk factors for seabather's eruption: a prospective cohort study. Public Health Rep. Jan-Feb 1997;112(1):59-62. [Medline].
Freudenthal AR, Joseph PR. Seabather's eruption. N Engl J Med. Aug 19 1993;329(8):542-4. [Medline].
Bernhardt MJ, Mandojana RM. "Seabather's eruption". Clin Dermatol. Jul-Sep 1987;5(3):101-2. [Medline].
Burnett JW, Calton GJ, Burnett HW. Jellyfish envenomation syndromes. J Am Acad Dermatol. Jan 1986;14(1):100-6. [Medline].
Fisher AA. Toxic and allergic cutaneous reactions to jellyfish with special reference to delayed reactions. Cutis. Oct 1987;40(4):303-5. [Medline].
Kettle M. Americans adrift in an ocean of fears. The Guardian Weekly. February 8, 2001:Available at http://www.vuw.ac.nz/~caplabtb/dprk/adrift.html.
Letot B, Kharfi M, Mandojana R, Piérard GE. [Undesirable reactions from contact with marine organisms]. Rev Med Liege. Jun 2000;55(6):531-7. [Medline].
Mandojana RM, Letot B. Historical outlook of aquatic biotoxicology and balneology as related to dermatology. Classification of aquatic dermatoses. Clin Dermatol. Jul-Sep 1987;5(3):1-7. [Medline].
Mandojana RM, Sims JK. Miscellaneous dermatoses associated with the aquatic environment. Clin Dermatol. Jul-Sep 1987;5(3):134-45. [Medline].
Wong DE, Meinking TL, Rosen LB, Taplin D, Hogan DJ, Burnett JW. Seabather's eruption. Clinical, histologic, and immunologic features. J Am Acad Dermatol. Mar 1994;30(3):399-406. [Medline].
Further Reading
Keywords
sea lice, Linuche unguiculata, L unguiculata, thimble jellyfish larvae
