Fire Ant

The bodies of fire ants, like all insects' bodies, are divided into three sections: the head, the thorax, and the abdomen, with three pairs of legs and a pair of antennae. Fire ants can be distinguished from other ants by their copper brown head and body with a darker abdomen. The worker ants are blackish to reddish, and their size varies from 2mm to 6 mm (0.12 in to 0.24 in). These different sizes of the ants can all exist in the same nest.

A typical fire ant colony produces large mounds in open areas, and feeds mostly on young plants, seeds, and sometimes crickets. Fire ants often attack small animals and can kill them. Unlike many other ants, which bite and then spray acid on the wound, fire ants bite only to get a grip and then sting (from the abdomen) and inject a toxic alkaloid venom called solenopsin, a compound from the class of piperidines. For humans, this is a painful sting, a sensation similar to what one feels when burned by fire—hence the name fire ant—and the after effects of the sting can be deadly to sensitive individuals. The venom is both insecticidal and antibiotic. Researchers have proposed that ant nurse workers will spray their brood to protect them from microorganisms.

The venom of fire ants is composed of alkaloids such as piperidine (see Solenopsis saevissima), and the sting swells into a bump, which can cause much pain and irritation at times, especially when stung repeatedly by several ants. The bump often forms into a white pustule, which is at risk of becoming infected if scratched; however, if left alone, it will usually flatten within a few days. The pustules are obtrusive and uncomfortable while active and, if the sting sites become infected, can turn into scars. Additionally, some people are allergic to the venom, and as with many allergies, may experience anaphylaxis, which requires emergency treatment. An antihistamine or topical corticosteroids may help reduce the itching.

Victims who experience severe or life-threatening allergic reactions to fire ant insect stings should visit a doctor or hospital immediately upon contact, as these reactions can result in death. These more severe reactions include severe chest pain, nausea, severe sweating, loss of breath, serious swelling, or slurred speech.