Can fire ants kill? What to know about these aggressive, invasive Florida insects

Anywhere in Florida you go, you'll find fire ants. Hopefully, you'll see them before they find you.

They're scary-looking. They're aggressive. They're tough to kill. The entire colony can band together and float to safety during a flood. They're seemingly everywhere. They get inside electrical boxes and utility rooms. Their sting is painful and can be fatal: a Georgia woman died over the weekend after suffering a severe allergic reaction to fire ant stings.

Few things in Florida are worse than looking down and realizing you've stepped in a fire ant mound. Here's what you need to know about these aggravating insects.

What are fire ants?

The red imported fire ant (Solenopsis invicta) is a medium-sized red and black ant with a pinched waist that builds mounds of soft soil. Worker fire ants can vary in size from 1/16 inch to almost 1/4 inch long.

Are fire ants native to Florida?

No. Fire ants are considered an invasive species in the United States. The red imported fire ant arrived by accident, either in Mobile, Alabama or Pensacola, Florida, from South America in the 1930s before spreading throughout the United States.

Fire ants are usually found in the southern region of the U.S. and in places as far north as Tennessee.

How do you tell if it's fire ants?

Fire ants build their colonies in dome-shaped mounds of soil that can reach 3 feet across and up to 18 inches in height. They like moisture and will nest near rivers, well-watered lawns and potted plants.  A red fire ant mound can include one or more queens, males for propagation and foraging workers that fan out to bring back food.

Do fire ants bite?

Yes, but that's not what hurts. Fire ants bite with their pincers to latch on to you, but then they use sharp stingers on their abdomens to inject venom.

If their mound is disturbed in any way, hundreds of aggressive fire ants will rush out and climb on whatever touched the mound, swarming over them to sting from multiple sides.

The painful sting creates an intense burning sensation, which inspired the fire ant name.

Why do fire ants sting hurt so bad?

The sting of a fire ant is 95% alkaloid, which produces the pain. The rest is a solution of proteins, peptides, and other small molecules that can produce an allergic reaction in hypersensitive individuals.

"Unlike honeybees, fire ants can continue to sting a victim numerous times," said Patrick DeMarco, a board-certified allergist and Immunologist with Allergy & Asthma Specialists of North Florida. "In fact, a single ant stings an average of three times before removal. Stings are most common and most painful during the summer when ants have the largest amount of stored venom."

When fire ants get on me, why do they all seem to sting at the same time?

Part of what makes fire ants so horrifying is how they seem to swarm up on you and then sting simultaneously. You may not even notice they're there until half your leg suddenly seems to be on fire.

"Fire ants are sensitive to vibration or movement and tend to sting when the object they are on moves," according to the Texas Imported Fire Ant Research and Management Project website. "For example, when fire ants swarm up a person’s leg, the person jerks or moves. Usually, whatever causes one ant to bite and stings triggers the other ants to sting to the same response."

Are fire ant stings lethal?

For some people, yes. A tiny amount of the population, around 1%, are hypersensitive to ant venom, and very young or old people or people with suppressed immune systems may react more severely to a fire ant sting.

However, even healthy people, if they get multiple stings, may have stronger reactions such as anaphylactic shock.

What should I do if I get stung by fire ants? What if I have an allergic reaction?

Immediately remove yourself from the area and brush off any fire ants still on you (swatting at them or trying to shake them off won't help). Quickly strip off shoes, socks, and any clothing near where you spotted them on your skin and inspect them before putting them back on. Ants can stay hidden for hours.

There's not much you can do about the burning pain but for most people it will fade after a few minutes. You can ice the sting with an ice pack or with ice wrapped in a towel, and raise the part of the body that was stung to reduce swelling. An antihistamine or hydrocortisone cream may help relieve itching, according to UCLA Health.

Small itchy bumps may occur where you were stung but they will generally fade in 30 to 60 minutes. You may see small blisters filled with yellow liquid (pustules) forming within the next 24 hours, along with intense itching that can persist for up to 10 days. Keep that area clean to avoid infections. If the blisters break, clean the area with soap and water and use an antibiotic cream.

But you should watch the area where you were stung for swelling, itching or redness and pay attention to any symptoms such as shortness of breath, thickening of the tongue, chest pain, cramping, nausea, or sweating that might indicate a severe allergic reaction. If that happens, call 911, and if you have an epinephrine shot (epi-pen) use it. Repeat after 5 to 15 minutes if you haven't improved. Whether your symptoms stop or not, get medical attention.

How can I avoid getting stung by fire ants?

• Watch your step. Don't disturb ant nests. Be careful where you stand.
• Wear shoes outside. A study showed that socks helped a lot, as that reduced the number of ants that reached the skin. If you're going to be walking where you can't see the ground, wear long pants and tuck the pants legs into your socks.
• If you garden, wear gloves.
• If you're camping, inspect your campsite carefully before setting up your tent or laying out your bedroll.
• Be careful picking up anything that's been on the ground a long time. Fire ants often congregate under food, trash or wood.
• Don't depend on insect repellents, fire ants don't seem to care and it won't stop them from stinging you.

Where are fire ants in the U.S.?

As of 2022, red fire ants have been predominately seen in 14 states: Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, New Mexico, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia.

How do I get rid of fire ants?

There are a variety of attacks, but the most effective way to kill a fire ant mound is fire ant bait, Wizzie Brown, a pest management specialist at Texas A&M University, told USA TODAY in an interview. For large infestations, you may want to consult a pest control service.

Homemade methods that have been persistently suggested over the years such as pouring club soda over the mounds or leaving instant grits nearby do not work.

"The rumor is that they eat the grits, which expand in their gut and make them explode," Lyle Buss from the insect identification lab of the Entomology and Nematology Department at the University of Florida said in 2014. "However, the workers don't actually eat the grits because they aren't able to eat solid food. They feed solid food to the ant larvae, which are able to digest it."

Can I kill fire ants with boiling water?

Yes, but it may be only a temporary solution. Boiling water can seem to be more environmentally friendly than other methods and pouring about three gallons of very hot, almost-boiling water onto a fire ant mound on a cool, sunny morning or right after heavy rainfall, when more ants are on the surface, will eliminate about 60 percent of the mounds treated. But it may not reach the queen.

The scalding water also will kill any grass and plants it contacts and you run the risk of getting burned yourself.

Are fire ants good for anything?

Fire ants are excellent predators. They can help control pests such as fleas and ticks, and they clean up dead animal carcasses. That may not be enough to get you to like them, though.