A sea lice infestation in Florida is spreading as tiny, stinging jellyfish larvae invade swimsuits.
The pests cause an itchy rash known as "seabather's eruption" and cases are being reported in higher-than-usual numbers along the Florida coast and throughout the
Gulf of Mexico, The Christian Science Monitor reported.
At the larval stage, which reaches its height in June, thimble jellyfish are about the size of a ground pepper speck and undetectable to swimmers.
The itchy rash is temporary, but severe cases can cause
flu-like symptoms, ABC News reported.
The creatures thrive in warm oceans from the Caribbean into the Gulf of Mexico and are most common where the Gulf Stream passes closest to the shore in places including Palm Beach County and Northern Broward County, the network reported, citing the Florida Department of Health.
Officials have posted signs and hung purple flags at beaches to warn of sea lice infestations.
The pests sting when they get trapped between beachgoers' skin and bathing suits, and their stings usually become noticeable to affected swimmers hours after leaving the water.
The itchy rash is known by a variety of names including beach lice, pika-pika, and
ocean itch, CNN reported. Children and surfers are at a greater risk for developing it, and those with allergies or compromised immune systems are more likely to experience the more sever reactions that include flu-like symptoms.
The jellyfish larvae became known as sea lice in the 1950s, but they are not the same as the parasitic creatures by the same name that
affect fish, the Panama City News Herald noted.
Those who have visited infested waters are encouraged to change out of bathing suits as soon as possible and rinse them with vinegar or rubbing alcohol. Washing the affected area with hot water and applying calamine lotion or oatmeal can relieve the uncomfortable symptoms of the stings.
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