DEET
Sand fleas also know as No-see-ums are not a cousin of the household flea and in fact isn’t even an insect, but a crustacean. Though the two are commonly grouped together, because they act much in the same way and both are definitely a pest. A female sand flea’s bite works much like the more common flea, because their bite injects an anesthetic and anti-coagulant into the victim before they suck out the blood they need to lay eggs. The major difference is the resulting bite, as one from a sand flea is far more painful and has a much longer duration than that of the common flea you find on pets.
Dealing with sand fleas is done similar to any other pest you find at the beach. Spraying yourself down with a light bug repellent is simply a must, preferably one that contains DEET. These fleas do not travel far from where they are born and you will rarely find them anywhere but the beach or near other bodies of water. One thing to listen for is a high pitched wine, as this sound is made by swarms of sand fleas. Being bitten by a single flea is painful enough, but being attacked by a small swarm of them can really ruin your day.