Sea lice aren't lice at all. They aren't even insects.
Actually, they are tiny larvae of the thimble jelly fish.
Sea lice stings typically occur when they become trapped between a bathing suit and skin.
The best way to avoid being stung is to be aware of reports and also to wear skin-tight swimwear. The tight swimwear will prevent the sea lice from getting between your swimsuit and your skin.
Symptoms of a sting include an itchy rash and small blisters. More severe reactions can include fever, chills, headache and nausea.
If you are stung, take off your swim suit and take a shower.
If a rash appears, use cooked oatmeal or calamine lotion over the area.