Location: Imported Fire Ant and Household Insects
2013 Annual Report
2. Define attractant characteristics of fire ant alarm pheromone.
3. Characterize environmental conditions in cargo containers and conduct initial probes of the use of the attractant to trap fire ants in cargo containers.
A lateral flow immunoassay (LFIA) for rapid, field detection of fire ants has proceeded. By law, regulatory personnel in the United States must prohibit movement of any fire ant-contaminated shipping commerce from entering non-quarantined areas. Unfortunately, cargo must be held until positive identification of the ant samples in the cargo is made. The current identification process requires extensive training of personnel and can delay movement of cargo by days. The LFIA accelerates the identification process at interception points such as quarantined boundaries and ports. The kit is easy to use and requires no previous training to make a positive identification for fire ants. The sample size is small, requiring one to five ant workers. The LFIA is based on immunological/nanoparticle detection of Solenopsis invicta venom. Monoclonal and polyclonal antibodies were designed to distinct regions of this protein. One monoclonal antibody is conjugated to gold particles and serves as the detection antibody while the polyclonal antibody serves as the capture antibody. From the moment a fire ant sample is collected, the assay may be completed in 5 to 10 minutes. Significant progress was also made in developing a second-generation prototype of a remote surveillance system. The system consists of a location for release of a fire ant specific pheromone that attracts worker ants up ramps that channel the ants into a position below a camera. A laser trip line activates the digital camera and photos transferred via WiFi to a computer for visual analysis. The next iteration will incorporate multivariate analysis of the ant image collected to automatically identify the ant image a Solenopsis or not. This system will have broad applicability to detection of invasive pests in general. The impact of the rapid fire ant identification kit and surveillance system on movement of goods is significant because it will provide a quick method to identify fire ants both at quarantine stations and to remotely detect fire ants in cargo containers and trucks which will shorten current long delays when ants are found in cargo moving out of quarantined areas. Fire ants are an invasive species that cost U.S. citizens at least 6 billion dollars annually. Indeed, these technologies have potential worldwide application to facilitate interception of fire ants at ports of entry.