ANNUAL ANT CONTROL ISSUE: Under Fire

Did you know that imported fire ants (IFAs) — which now infest more than 300 million acres in the United States and Puerto Rico — have recently been reported invading health care fa-cilities and stinging patients? Maybe this has always occurred and was unrecognized, but regardless, fire ant stings in nursing homes, personal care homes and hospitals are currently a hot topic in the news. Guess who gets the blame when one of these events occurs? You’re right, the PCO holding the contract on that particular facility. What’s the basis of the lawsuit? Failure to provide adequate pest control — when the pest control contract included “ant service.”

When someone gets attacked by fire ants at a nursing home or other facility 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 is 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 health-care facilities? The following is a summary of fire ant prevention and control measures in and around health-care facilities.

KEEPING IFAs AWAY FROM PATIENTS. Extremes in weather may explain occasional movement of fire ants into inhabited dwellings. During spring, when the soil is saturated, IFA colonies may move inside looking for drier conditions. The same is true for prolonged periods without rain — ants will move toward moisture if it is found inside. Another important factor facilitating movement of IFAs to the inside of a building is proximity of ant mounds to the foundation of a building. Foragers from mounds located next to a building’s foundation have a greater chance of foraging inside the building than foragers from mounds located at some distance away.

Special care is required to ensure that patients in long-term care facilities are not stung by fire ants. These are special needs patients — they may not be aware of their surroundings, may be immobilized by disease or otherwise incapacitated and they may be unable to respond if ants come into contact with them. Once patients have come into contact with foraging ants, a variety of external stimuli, including movement of the patient, might trigger a stinging event, leading to multiple stings in a short period of time. Some common sense suggestions for prevention of indoor and outdoor fire ant infestations are presented below and on page 48. Some of these recommendations are obviously not related to pest control (instead to facilities management, patient management or patient behavior), but are included here for informational purposes.
 

RECOMMENDATIONS FOR PREVENTION OF OUTDOOR FIRE ANT INFESTATIONS • The first 25 to 50 feet around the outside of a building should be considered a critical “surveillance” zone and regularly surveyed for fire ant infestation. • Allow 18 to 20 inches of clear air space between the building and the mature height and width of ornamental plants. • If irrigation is used, make sure sprinkler heads are pointed away from the building and not positioned so as to wet the building, thus providing moisture for insect infestation. • Keep the soil grade sloping away from the building to prevent accumulation of water against the foundation. • If rain gutters are used, make sure that down spouts are clear and water runs freely away from the facility. • Contract with a pest control firm to routinely inspect and, if appropriate, apply insecticides to keep the perimeter of health-care facilities free of fire ant infestations..

FORMULATION OF AN ANT POLICY. Health care facilities located in geographic areas within the range of fire ants may choose to develop an “ant policy” to document fire ant activity and establish written guidelines for patients and staff. Pest control at health-care facilities is almost always provided by contract with a pest management company; however, the overall pest management process involves the watchful eye of health-care providers, maintenance and housekeeping staff as well. Some form of pest documentation should be in place (e.g., a pest sighting log) to inform the pest controller of pest sightings, locations, times, etc. Moreover, sighting of ants in patient rooms should trigger an established plan of action.

ONLINE ONLY: Map Showing First Occurence Of RIFA, Solenopis invicta To view an interactive map that shows the first occurence of red imported fire ant Solenopis invicta throughout the United States, CLICK HERE.

Management and staff should be aware that not all ants inside health care facilities are fire ants. To be on the safe side, when fire ants are spotted in a room, the patient should be removed until the pest control company has had a chance to investigate and perform adequate control measures. Having an “ant policy” may reduce liability in the event of a stinging incident — in effect, showing that the facility was diligent in their efforts to prevent ant invasion. A modified “ant policy” developed by a nursing home for the prevention of fire ant attacks is provided on page 56. (Editor’s note: Even though the development of such an “ant policy” is the responsibility of the health-care facility [and not the PCO], pest control personnel should be familiar with these policies and know which parts are related — directly or indirectly — to the pest control program.)

FIRE ANT CONTROL. The following are some tips for fire ant inspection and treatment.

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 and note locations of expansion joints within the building, if 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 should be aimed at those mounds within the first 10 to 15 feet of the building. In this zone, “quick” treatments are needed (you can’t wait on a bait). Any mound touching the building should be treated using a mound drench. Follow label directions carefully; generally mound drenches require 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 at or under the edges of sidewalks or landings at doors. This is similar to a termite treatment.

Another treatment that might be considered along the foundation is application of a granular insecticide. Sprinkle (read directions for guidance) a layer of the granules several inches wide to form a protective barrier.  

The next area to consider is the lawn. Baiting is the treatment of choice and several products are available. Products containing growth regulators have a slower mode of action. 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, ants readily accept it.

RECOMMENDATIONS FOR PREVENTION OF INDOOR FIRE ANT INFESTATIONS (Note: Many of these are not the responsibility of the pest management professional but should be discussed with management.) • Determine if facility’s pest service contract covers fire ants • Vigilance to identify fire ant infestation should be increased during weather extremes • Do not allow beds or linens to touch the wall or floor • Limit food in the bed as much as possible • Check mattresses for food accumulation • Place food left in the room in well-sealed (air-tight) containers • Keep the outside of intravenous inserts as dry as possible • Make sure that catheters are properly functioning • Avoid accumulation of water or food particles under base plates during floor sweeping or mopping

Baits can be broadcast or used to treat individual mounds. Broadcasting gives uniform distribution across the area and every ant in the treated area has access to bait. Generally, baits are broadcast at a rate of 1 to 1½ 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 retreatments as necessary.

Red Imported Fire Ant Fact Sheet Latin Name: Solenopsis invicta Description: Reddish brown, 1/8- to 1/4-inch long. Since they look like other types of ants, their aggressive behavior and earthen mounds best identify them. Territory: About 300 million acres covering much of the southern half of the U.S. The range now includes most of the Southeast U.S., irrigated areas in the Southwest U.S., parts of the East and West Coasts and Puerto Rico. Habit: Earthen mounds are typically 3 to 36 inches high, although in some soil types, there will be no visible mound. Ants are aggressive when mound is disturbed. A mature colony consists of 200,000 to 400,000 workers. Workers use foraging tunnels 50 to 100 feet long to collect food for the colony. Reproduction: A colo-ny’s queen produces up to 800 new workers per day. Some colonies support more than one queen, making eradication difficult for pest management professionals. Diet: In health-care facilities, fire ants dine on meal debris, soiled linen, intravenous tubes and needles and body oil build-up on surfaces. Human health risk: Fire ant workers both bite and sting. The sting causes a subsequent burning sensation and wheal. Sterile pustules develop in everyone who is stung. About 1 percent of the population is allergic to the sting. Reactions vary from local skin reactions to anaphylaxis. Control methods: Experts suggest that pest management professionals broadcast bait as well as drench mounds in high-traffic areas.

CONCLUSION. The preceding procedures (including inside and outside, chemical, non-chemical and behavioral) may seem trivial or impractical; however, they may be needed to prevent fire ants from entering a building.
Consider what you would want done if you had a family member in a facility your pest control company 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 601/576-7512 or via e-mail at jgoddard@pctonline.com.

SAMPLE OF A FIRE ANT POLICY FOR A HEALTH CARE FACILITY (Please note that this is intended as a guide and not an all-encompasing strategy for fire ant control.) 1. This facility maintains an ongoing pest control program. Pest control services, including those providing surveillance for and extermination of fire ants, are provided by a licensed pest control operator on a monthly basis and as needed. The contract for pest control services is maintained in the business office. 2. Nursing staff will inspect each room daily for evidence of fire ants and other insects. Sightings will be recorded in an insect-sighting log. 3. In the event that ants are detected in the facility, the pest control firm will be contacted and the area treated. 4. If fire ants are noted in a patient’s room, the patient will be removed from the room until the pest control operator has had a chance to investigate and perform adequate control measures. 5. If ants are detected on a resident, the patient will be assessed immediately and appropriate care provided. The patient’s family and physician will also be notified immediately. The area will be treated for ant infestation. All other residents and their rooms will be checked for ants. An incident form will be completed. 6. The housekeeping/maintenance supervisor or his/her designee will make daily rounds on the grounds of the facility to inspect for ants and other pests. Lawns will be carefully inspected weekly during ant season and treated (when ants found) with an ant insecticide and/or bait by the housekeeping/maintenance department and monthly by a licensed pest control operator. Logs will be kept for dates of lawn treatments. 7. Garbage and trash are to be removed from the facility daily. 8. Maintenance staff will look for and correct any water leaks within the facility on a regular basis. 9. Families bringing food to residents must use air-sealed containers for the food.