PCOs may be liable when fire ants sting nursing home residents at a property with which they have a contract. Are you prepared to deal with this growing problem?
Want to hear some scary news? Fire ants — which now infest more than 300 million acres in the United States and Puerto Rico — have recently been reported invading nursing homes and stinging the patients. Maybe this has always occurred and was unrecognized, but regardless, fire ant stings in nursing homes is currently a hot topic in the news. Guess who gets the blame when one of these events occurs? You’re right, the pest control operator holding the contract on that particular facility. What’s the basis of the lawsuit? The basis is that there was failure to provide adequate pest control — when the contract said that the pest service included "ants."
A recent article in the Annals of Internal Medicine (1999, vol. 131, page 424) carefully examined two cases of fire ant stings in nursing homes and mentioned two more (for a total of four) stinging events since 1994. Two of the patients subsequently died. In all cases, the victims were poorly mobile, neurologically compromised persons who could not withdraw from attacking fire ants.
When someone gets attacked by fire ants at a nursing home where you have the pest control contract, it’s a no-win situation. There’s no good defense, other than maybe to contend (and rightly so, in my opinion) that fire ant invasions are unpreventable in some cases — almost like lightning or tornadoes. Fire ants are so widespread and constantly foraging for food that it seems almost impossible to guarantee that they will NEVER enter a facility.
What can be done? Is there any way to prevent fire ant infestations in nursing homes? The following is a summary of fire ant biology and control measures in and around nursing homes.
FIRE ANT BIOLOGY. The fire ant is basically a soil-nesting ant, with the nests occurring in open areas such lawns, parks, pastures, fields, road- sides, etc. The worker ants forage out from the mound for food and will feed on a variety of substances, i.e., living insects, honeydew and, to some degree, carrion. As mounds build up in the lawn around buildings, they may eventually be located under sidewalks, splash plates, landscape timbers or adjacent to the building foundation. Mounds located near the building increase the chances for ants to forage into buildings. Adverse conditions such as extended periods of dry weather or heavy rains to the point of soil saturation will increase this probability.
Given that fire ant infestations within a building probably have their beginnings outside, the exterior of the building is the place to start. The following steps — developed with the cooperation of Dr. James Jarratt, Mississippi Cooperative Extension Service — are the basics of a good fire ant management program:
Inspection. The first 10 to 15 feet around the building are the most critical. Look for mounds touching the building, evidence of mounds under splash plates, mounds under sidewalks approaching the buildings, mounds under concrete pads at doors or evidence of moisture accumulation around the foundation (also note locations of expansion joints within the building, if there are any). After checking this area, move to the lawn area at large. This may or may not be practical, depending on the size of the lawn area, but I would suggest moving out at least another 150 to 200 feet from the building. If mounds are present, this should be noted.
Treatments. The first and most critical treatment is those mounds that are within the first 10 to 15 feet of the building. Any mound touching the building should be treated using a mound drench with a product such as chlorpyrifos (23.5 percent). Mix the product using 2 fluid ounces per 4 gallons of water and apply about 1 gallon per mound. A suggestion: use an injection rod and push the rod to the bottom of the mound and start treating from the bottom up. Do not use high pressure because you don’t want to wash soil from under the footing. Follow the same procedure for those mounds that might be at or under the edges of sidewalks or landings at doors. This is similar to a termite treatment.
The next area to consider is the lawn. Baiting is the treatment method of choice, and two products, Amdro and Logic, are widely used. Logic, by Novartis, is an effective material; however, it’s a growth regulator and has a slow mode of action. Amdro, by American Cyanamid, is faster, and might be more desirable under the circumstances. Baiting seems to work best when there are a number of larvae present in the mounds. Larvae require a constant supply of food and worker ants are constantly foraging for available food. If the bait is applied at this time, the ants readily accept it.
Baits can be broadcast or can be used to treat individual mounds. Broadcasting gives uniform distribution across the area and every ant in the treated area has access to bait. It should be broadcast at a rate of 1.0 to 1.5 pounds per acre.
I would prefer to see about four to eight hours of dry weather following the application. It will take seven to 14 days before noticing a decline in ant numbers.
Continue to monitor the building and the area for the presence of ants. Repeat treatments as necessary.
CONCLUSION. The previous procedures may seem impractical; however, it is what’s required to prevent fire ants from entering a building. Consider what you would want done if you had a family member in a facility you had under contract.
The author is a medical entomologist for the Mississippi Department of Health and Clinical Assistant Professor of Preventive Medicine at the University of Mississippi Medical Center, Jackson, Miss. He can be reached at jgoddard@pctonline.com or 601/576-7512.
SIDEBAR:
A Two-Fisted Punch
PCOs are constantly on the lookout for treatment methods and products that combat fire ants. One such method involves a direct liquid insecticide application to the fire ant nest or mound and a follow-up broadcast granular or liquid insecticide application on the customer’s lawn. To be effective, mound drenches should enter the galleries and trickle down into the mound, contacting the ants. After initial control is established, it is often possible to maintain control with a twice-a-year broadcast application on the customer’s lawn using a granular product with a residual of several months, such as Talstar PL Granular Insecticide from FMC, according to the company.
FMC has a method it calls the "Double Shot Method." It involves using Talstar Lawn & Tree Flowable insecticide to drench the mound and then a granular product (or, a broadcast application of Talstar Lawn & Tree Flowable insecticide) to keep foragers and new queens off of the property for months, the company says.
Source: FMC Corporation