What Are Sand Fleas and How Can Their Bite Affect You?

When people talk about sand fleas, they may be talking about different organisms: Sand flies, which live in and around aquatic habitats, and sand or mole crabs, which are crustaceans that live on the beach and don't bite humans.

Really, "any flea that comes out of a sandy area, people call a sand flea," Nancy Hinkle, Ph.D., a professor at the University of Georgia's Department of Entomology, told Health.

But actual sand fleas are technically known as chigoe fleas, or Tunga penetrans, and they're pretty detrimental to human health, but not necessarily because of the bite. Luckily, these sand fleas are extremely rare in the U.S., but that doesn't mean you'll never come across them, especially if you travel outside the country at some point.

If you're bitten by one of those creatures, you might notice sand flea bites—like a cluster of small red bumps—on your skin.

To help you with everything you need to know about sand fleas, Health spoke to Hinkle, an entomologist (aka, a bug expert). Here's what to understand about sand fleas, their bites, and other damage these parasites can cause.

What Are Sand Fleas?

Chigoe fleas are known by quite a few different names:

• Jiggers
• Niguas
• Chicas
• Picos
• Piques
• Suthis

Adult female fleas pose the most risk to humans. While both adult male and female fleas feed on warm-blooded hosts, like humans, the adult mated females burrow into the skin of humans (more on that later).

Where Do Sand Fleas Live?

These sand fleas are usually found in tropical areas and sandy climates like beaches, stables, and farms. You may find them in:

• Mexico
• South America
• The West Indies
• Africa

Just because we don't currently see Tunga penetrans in the U.S. doesn't mean we couldn't: If you were to travel to a beach in the Caribbean, for instance, and come into contact with the fleas, you could potentially pick them up there and bring them back to a beach in the U.S.

"That is a risk—[if] you have been walking along a Florida beach, you could start an infestation of chigoe fleas in Florida," Hinkle said.

What Do Sand Flea Bites Look Like?

Sand flea bites appear as clusters of small red bumps on your skin. The initial symptoms of a sand flea bite infection usually develop only after the females are in their engorged state.

Sand fleas reproduce with the help of humans. Female sand fleas burrow into the skin (usually the feet), and male sand fleas briefly meet them there to mate, Hinkle said.

This is technically called tungiasis, or an infestation by the Tunga penetrans. The female's head will be burrowed into the skin, but her rear end isn't, which allows her to expel eggs to the ground after mating. The female dies after expelling eggs—about 100 or so over a two-week period—and then will fall out of the foot to the ground.

What Are the Risks of Sand Flea Bites?

Usually, people don't notice sand flea bites as they're happening. The fleas are tiny and usually attach themselves to the ankles or feet, meaning you might not even notice when they first make contact with the body.

"That's the risk there: You have this lovely vacation, you get back on the plane—a couple of days later, you notice irritation on your big toe, [and] it's hurting to walk around," Hinkle said. This inflammation and ulceration may become severe, and multiple lesions can cause difficulty walking.

But the bite itself—and even strictly the burrowing—isn't necessarily the problem; it's the aftermath. The opening created when the female burrows into the skin can put you at risk of contracting infections. The female sand flea "creates this opening that allows bacterial infection," which can lead to a tetanus diagnosis or one of gangrene, Hinkle said.

How To Treat Sand Flea Bites

Treatment should include a sterile surgical removal of the sand fleas. After removing the fleas, they should be covered with an appropriate dressing. If your tetanus vaccination isn't up to date (if you haven't had a booster in over 10 years), you should also be treated with a tetanus vaccine or booster.

Topical medications such as dimethicone—commonly found in head lice treatments—are highly effective for sand fleas.

How To Prevent Sand Flea Bites

Repellents like DEET-containing bug sprays can effectively keep fleas away, as can coconut oil. That said, it's essential to check the label of your preferred bug spray to see how frequently you need to apply it to ensure you're constantly protected.

The next time you plan a vacation, it can't hurt to look ahead to see if sand fleas are problematic on the beaches you plan on visiting. That way, you can ensure you've taken precautions to protect yourself from the sand fleas' bites.

A Quick Review

Sand fleas are pesky bugs that burrow into your skin and cause irritation and inflammation. Although they aren't common in the US, they are common in places like Mexico and Africa.

So before you plan your vacation, make sure the place you're heading to doesn't have sand fleas, and if they do—plan, and pack a lot of bug spray.