Fire ant attacks on patients in nursing homes: an increasing problem.

We review the medical reports of fire ant attacks on residents of nursing homes in the context of the medical entomology of these insects, and present recommendations to prevent and manage future attacks. Two reports were recent cases, while a computer-assisted search yielded four other similar cases of attacks by foraging fire ants in the last 10 years. One patient experienced an anaphylactic reaction and 4 patients died within 1 week of the attack. Ants were usually noted in health care facilities days before the attacks. The presence of fire ants around immobile, often cognitively impaired, patients seems to be the primary risk factor for massive fire ant attacks. Health care providers and administrators in fire ant endemic areas must be aware that the presence of fire ants in hospitals and nursing homes represents a hazard. Fire ant infestation can lead to sting attacks on patients, causing respiratory tract obstruction, worsening of pre-existing medical conditions, or frank anaphylaxis. All the attacks reported here have resulted in legal action involving physicians and health care facilities.