Evaluation of a lateral flow immunoassay for field identification of Solenopsis invicta (Hymenoptera: Formicidae) in Australia

Authors: Valles, Steven; WYLIE, ROSS - Department Of Agriculture - Australia; BURWELL, CHRIS - Queensland Museum; MCNAUGHT, MELINDA - Department Of Agriculture - Australia; HORLOCK, CHRISTINE - Department Of Agriculture - Australia

Submitted to: Austral Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/7/2017
Publication Date: 8/9/2017
Citation: Valles, S.M., Wylie, R., Burwell, C., Mcnaught, M., Horlock, C. 2017. Evaluation of a lateral flow immunoassay for field identification of Solenopsis invicta (Hymenoptera: Formicidae) in Australia. Austral Entomology. https://doi.org/10.1111/aen.12297.
DOI: https://doi.org/10.1111/aen.12297

Interpretive Summary: The red imported fire ant is a highly invasive species that was introduced into the United States in the 1930s and Australia in the 1990s. The ant causes approximately US$6 billion in damage annually to livestock and agricultural production and poses a serious threat to human health. On both continents, there remains an acute need for a rapid, field portable method for the identification of these ants to limit their spread and prevent new incursions. USDA-ARS scientists at the Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) and USDA-APHIS (Biloxi, MS) have developed a lateral flow immunoassay that provides a rapid and portable method for the identification of Solenopsis invicta imported fire ants. The test was evaluated against Australian ant species to further establish the fidelity of the test and usefulness in Australia. This Solenopsis invicta device provides a new tool for regulatory agencies in the United States and Australia to enforce quarantine protocols, limit the spread of this invasive ant, and detect new incursions.

Technical Abstract: In an effort to improve surveillance capacity for the exotic red imported fire ant, Solenopsis invicta, a lateral flow immunoassay (LFA) was recently evaluated by Biosecurity Queensland staff in Australia. The purpose of the research was to assess the ability of the fire ant LFA to discriminate S. invicta from ants found in Australia, and to conduct the first field evaluation of the test. Thirty-six species of ants, collected mainly from Queensland, were evaluated by the LFA, including species from the Dolichoderinae (n = 7), Formicinae (n = 14), Myrmeciinae (n = 1), Myrmicinae (n = 10), Ponerinae (n = 3), and Pseudomyrmecinae (n = 1) subfamilies. The fire ant LFA test correctly identified S. invicta in every instance. No cross reactivity was observed toward the other ant species. Field tests by staff previously unfamiliar with the test resulted in suggestions for improving ant collection and manipulation. The fire ant LFA appears to be suitable for use in Australia for rapid confirmation of potential new detections of S. invicta.