What's Giving Some Beachgoers Rashes? Get the Facts.

Lifeguards reported this year’s first cases of sea lice, which aren’t lice at all.

Sea bather’s eruption is leaving some U.S. beachgoers itchy.

On Monday, lifeguards in Pensacola, Florida, raised the purple flag to warn beachgoers of dangerous wildlife in the water. Swimmers there had been leaving the shore feeling fine, only to find the next day that they had red, itchy rashes. This delayed onset gives the condition its common name: sea bather’s eruption, or sea lice.

And although there have been no reports of serious cases this year, extreme symptoms of sea bather’s eruption can include fever, nausea, and chills, usually affecting children and people with allergies.

Worried about your vacation plans? Here’s everything you need to know.

The so-called sea lice that just appeared in Florida aren’t lice at all—they seem to be

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