PHILADELPHIA -- (September 21, 1999) Fire ants attack people who disturb their ant mounds, but they will also attack humans indoors. The September 21, 1999, issue of Annals of Internal Medicine carries two case reports of fire ant attacks in two Mississippi nursing homes. Two elderly patients were found covered with ants, with ant trails leading from the floor to their beds. One died five days after the attack, the other 13 months later. Both facilities had been treated by pest control services in the previous days.
Fire ants arrived in the U.S. about 60 years ago and have spread across the Southeastern U.S. and Puerto Rico. They have consumed most of the native black ant population in the Southeast and have recently been spotted in some Western states, says Richard D. deShazo, MD, lead author of the Annals article, director of the division of allergy and immunology and chairman of the department of medicine at the University of Mississippi Medical Center.
Fire ants sting and kill invertebrates as their primary food source but have been known to kill farm animals if other food isn't available. According to deShazo, the medical complications of fire ant stings can range from mild irritation at the sting site to death from a generalized allergic reaction, depending on the number of stings and the physical condition of the victim.
Fire ant stings at the ant mounds or outdoors have caused at least 80 deaths. But, in 1989, the first case of fire ants attacking humans inside a building was reported. Since then, seven more indoor attacks on people in six states have been reported, six of these by deShazo.
In the ten reported indoor attacks, four of the patients did not suffer clinical complications; a five-day old baby, attacked in a crib, went into shock and coma but lived; a developmentally delayed two-year old suffered damage to his cornea when fire ants attacked his eyes; two older nursing home patients died within six days of attack.