Brantly Keiek, WEAR Staff

Pensacola, FL. (WEAR) — A dip in the Gulf of Mexico may make you itchy.

Sea lice have moved into the waters along the Northwest Florida coast. On Monday, lifeguards at Pensacola Beach hoisted purple flags warning beach-goers of the hazardous marine life.

Sea lice are not actual lice, which are small parasites. In Florida’s waters, sea lice are usually the larvae of the thimble jellyfish. People affected by sea lice may feel a prickling sensation on their skin while in the water, but the rash caused by the microscopic organisms typically occurs several hours after exposure.

Pressure and friction on the baby jellyfish cause the stinging cells, known as nematocysts, to fire and trigger a reaction on the skin. The Florida Department of Health says to limit the chance of a reaction, “Swimmers should avoid wearing t-shirts while in the ocean… There is some evidence that use of a topical sunscreen or suntan lotion may actually protect skin from penetration by the nematocysts.”

If stung by sea lice or other jellyfish, the National Institute of Health recommends applying vinegar to the skin to prevent further discharge of unfired nematocysts. People stung can treat the rash with antihistamines and over-the-counter hydrocortisone creams.

Sea lice is also referred to as “Sunbathers Eruption.” The name “sea lice” dates back to the mid-twentieth century, when coastal residents in the United States created the term. Scientists discouraged use of the term so that the jellyfish larvae are not confused with actual lice.