Recognition:
(1) location within known range: South America, Southern United States (including California), especially the Southeast
(2) by a trained entomologist. The predominant species is Solenopsis invicta. The adult ants are 5-6 mm in length. The color may vary with geographical location.
(3) clinical features with severe burning and itching shortly after envenomation, followed by a localized hive which develops into a necrotic lesion (sterile pustule).
(4) characteristic response to disturbing the colony mound, with swarms of ants attacking anything foreign
If fire ants are seen inside of a health care facility, then an active infestation should be assumed until proven otherwise. The building(s) and perimeter about the facility should be inspected. The ants are attracted to electrical fields and may be found in the building's electrical wiring and within electrical equipment, including computers.
If an infestation is identified, then chemical pesticides (baits, aerosols, sprays, dusts) need to be applied inside and out. The key is to kill the colony's queen ant. The most effective method to destroy a colony is to use baits of corn grits impregnated with soybean oil containing slow-acting insecticides. Worker ants identified within a facility should be exterminated with liquid pesticides.
Reinfestation of a facility is relatively common. Once an infestation has been documented, quarterly inspections of the facility should be conducted.
People at risk from repeated attacks include:
(1) infants
(2) neurologically impaired persons
(3) immobile persons
These persons should be considered at risk as long as fire ants are identified in the facility.
NOTES:
(1) Placing the legs of beds in water containers may help reduce forays by the ants (used by the British in India during the 19th Century).
(2) "Formiciasis" is the term used for poisoning from ant bites.
