New Test Quickly Detects Red Imported Fire Ants

Dan Industry News Release

By Sandra Avant, USDA Agriculture Research Service

red imported
A new test kit, developed by U.S. Department of Agriculture (USDA) scientists, could limit the spread of red imported fire ants.

Since the red imported fire ant invaded the United States more than 85 years ago, it has infested 367 million acres. Each year, imported fire ants cost Americans $6 billion to control and repair damage. Also, these ants inflict a venomous sting that’s potentially life-threatening to humans and small animals.

The new test was developed by Agricultural Research Service (ARS) and Animal and Plant Health Inspection Service (APHIS) scientists. Entomologist Steven Valles, at the Center for Medical, Agricultural and Veterinary Entomology (CMAVE) in Gainesville, Florida, developed novel antibodies that bind to a protein in the fire ant’s venom. Valles, along with ARS and APHIS colleagues, used these antibodies to develop a portable, easy-to-use test kit.

The new test, which specifically targets red imported fire ants, was developed primarily for APHIS’ use at truck inspection stops to help prevent ants from crossing into ant-free areas. Trucks traveling from a fire ant quarantined area to a location not under quarantine must be certified free of imported fire ants before they can move on, according to Valles. If ants are detected, the shipment must remain in an inspection holding area until the ants are identified.

Currently, identifying ants at inspection stations takes hours or even days. The new test identifies them in just 10 minutes. No special training is required to use the test kit, which consists of a plastic tube, a pestle and a test strip that gives a positive or negative reading.

The test can be used at any location where cargo is imported or exported, according to Valles, who works in CMAVE’s Imported Fire Ant and Household Insects Research Unit. Other countries, including Australia, Taiwan, and New Zealand, have expressed interest in the test kit.

Read more about this research in the December 2016 issue of AgResearch magazine.

ARS is USDA’s chief in-house scientific research agency.

Image credits: (Top left) Typical colony of the red imported fire ant, Solenopsis invicta Buren. Photograph by Sanford D. Porter, USDA, Gainesville, FL. Courtesy of UF/IFAS, Entomology & Nematology.

 (Bottom right) Mound of the red imported fire ant, Solenopsis invicta Buren, in St. Augustinegrass. Photograph by Rudolf Scheffrahn, University of Florida. Courtesy of UF/IFAS, Entomology & Nematology.