TAMPA, Fla. (WFLA) — Swimmers and surfers enjoying the waves along Brevard County’s Cocoa Beach were forced to fend off pesky ‘sea lice’ as Hurricane Lee threatened to bring dangerous surf to much of the Atlantic Coast.

The term “sea lice” originated during the 1950s and was used by locals to describe an itchy rash experienced after swimming along 250 miles of Florida’s southern Atlantic coastline between the months of March and August.

According to the Florida Department of Health, periodic outbreaks of the ‘sea lice’ have likely existed for centuries.

“Fishermen have long been acquainted with it, affirming reports in Cuba, Puerto Rico, Mexico, and the Caribbean islands,” one study said about the rash. “Names such as ‘sea poisoning,’ ‘sea critters,’ and ‘ocean itch’ have been used as descriptions of this seasonal affliction.”

What is ‘sea lice?’

When marine biologists at the University of Miami analyzed water samples collected along the affected coast, they concluded that the larval form of Linuche unqui culata, also known as a thimble jellyfish, was responsible for the outbreaks. The tiny organisms which are barely visible to the naked eye contain stinging structures known as nematocysts.

When the larvae become trapped and agitated under bathing suits worn by swimmers, their stinging structures fire. The FDOH said it’s not unusual to see 200 or more stings under a person’s bathing suit.

Treatment options

Those who experience the rash can use an antihistamine, such as diphenhydramine for the itching, plus an over-the-counter 0.5% hydrocortisone cream for the rash areas.

Good personal hygiene will also help patients of any age to avoid secondary bacterial infections.