21 September 1999
Ants in your pants?
by Kate Melville
Remember those old Z grade horror films with spiders, monsters and ants? Well you can now start to rebuild your fear of ants! Fire ants have been known to attack people who disturb their mounds, but there are now recorded cases where they have also attacked humans indoors.
The September, issue of Annals of Internal Medicine (USA) has two case reports of fire ant attacking Mississippi nursing homes. In each case an elderly patient was found covered with ants, with ant trails leading from the floor to their beds. One died five days after the attack, the other a little over a year later.
Fire ants first arrived in the U.S. about 60 years ago and have spread across the Southeastern U.S. and Puerto Rico. 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. The medical complications of fire ant stings can range from mild irritation at the sting site to death from a generalised 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 in the US, 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. 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.
Any sighting of a swarm of ants indoors is a warning. Residents and caregivers of infants, children and bedridden people, such as patients in health care facilities, should be closely watched until the ants are eliminated. Eliminating fire ants is not easy - the colony cannot be destroyed unless the queen ant is killed and should probably be done by a professional pest control service. Unfortunately in the cases where the two fatalities occurred both had been treated by pest control services in the previous days!