Fire ant sting
A fire ant sting usually shows up as a burning red welt that develops a sterile white pustule within a day, red base, white or yellow pustule centre, appearing immediate burning. It peaks around pustule at 24 hours and generally lasts pustule 3 to 10 days, mark can persist for weeks. Multiple stings in a ring or cluster — the ant grips and pivots is the usual arrangement.
| Looks like | a burning red welt that develops a sterile white pustule within a day |
|---|---|
| Pattern | multiple stings in a ring or cluster — the ant grips and pivots |
| Size | 2–10 mm |
| Appears | immediate burning |
| Worst at | pustule at 24 hours |
| Lasts | pustule 3 to 10 days, mark can persist for weeks |
| Itch | ●●●●○ 4/5 |
| Pain | ●●●●○ 4/5 |
| Usually on | feet, ankles, lower legs, hands |
| Active | March to November, daytime, especially after rain when mounds are rebuilt |
How to tell it apart
Fire ants sting rather than bite: they anchor with their jaws and sting repeatedly in an arc, which produces a curved group of welts rather than a single mark. The sterile pustule that appears the next day is close to unique among American stinging insects and is the most reliable identifier.
Where and when you meet it
Habitat: open sunny ground — lawns, parks, roadsides and pasture across the Southeast and parts of the Southwest.
Across 24,580 verified US records in the GBIF biodiversity database, sightings of Solenopsis invicta concentrate in March to May. That is the window when bites are most likely — it is observation data rather than a guess, and it shifts with latitude.
States with the most recorded sightings
- Texas 11,723 records
- Florida 6,712 records
- North Carolina 1,197 records
- Georgia 912 records
- Louisiana 768 records
- Mississippi 763 records
- South Carolina 693 records
- Alabama 629 records
- California 261 records
- Arkansas 168 records
- Virginia 139 records
- Oklahoma 111 records
Record counts reflect where people report and identify specimens, not exact abundance. They are useful for ruling a species in, not for ruling it out.
Where it is recorded
| Country | Records | Peak months there |
|---|---|---|
| United States | 24,580 | March to May |
| Brazil | 558 | October |
| Australia | 277 | May, July |
Verified records from the GBIF biodiversity database across the seven countries we cover. A country missing from this table means we have no records for it, not that the species is absent.
What it means for you
A whole colony responds at once, so a few seconds standing on a mound produces dozens of stings — which is why the reaction can look alarming even in someone not allergic. The medical concern is anaphylaxis in sensitised people, and anyone who has had a severe reaction should carry an adrenaline auto-injector.
Seek medical care if
Call emergency services now for difficulty breathing, swelling of the lips, tongue or throat, dizziness or fainting, or hives spreading away from the bite.
- difficulty breathing, throat tightness, dizziness or hives away from the sting site — call emergency services
- a previous severe reaction to any sting
- stings covering a large area, particularly in a small child
Care at home
- move away from the mound and brush ants off — do not stand still
- wash and apply a cold pack
- leave the pustule intact; breaking it invites infection
- antihistamine for itch
Preventing the next one
- look before standing or sitting on grass in fire ant country
- closed shoes outdoors
- treat mounds in the garden rather than kicking them
Common questions
How do I know it was a fire ant?
Fire ants sting rather than bite: they anchor with their jaws and sting repeatedly in an arc, which produces a curved group of welts rather than a single mark. The sterile pustule that appears the next day is close to unique among American stinging insects and is the most reliable identifier.
How long does a fire ant sting last?
Typically pustule 3 to 10 days, mark can persist for weeks, peaking around pustule at 24 hours.
When is it a problem?
Seek care for: difficulty breathing, throat tightness, dizziness or hives away from the sting site — call emergency services; a previous severe reaction to any sting; stings covering a large area, particularly in a small child.
Can it transmit disease?
No human disease is known to be transmitted by this species in the United States. The practical risk is infection from scratching.
Get a photo assessment in the app
Everything above is free to read. The app adds what a page cannot: point your camera at the bite and get an assessment of the most likely cause, a severity read, and a day-by-day care plan — including the specific signs that mean you should be seen.
iPhone and iPad. Free to download.