There are parasitic flies, ants, and other organisms that are currently being evaluated for use in fire ant infested areas of the United States. One solution under investigation is infesting fire ants with the microorganism T. solenopsae. In 1973, it was discovered in Brazil and is the most common pathogen found in fire ants in South America. The pathogen T. solenopsae infects ant colonies and chronically weakens them. The microorganism doesn't harm plants or native ant species.
Workers transmit the pathogen to the queen through food exchange.
The disease slowly reduces her weight. She lays fewer and fewer eggs, all infected with the pathogen, further weakening the colony. Colony elimination can take from nine to 18 months. Fire ants infected with a microorganism were released in Arkansas and Oklahoma to reduce the numbers of the imported ants. Scientists from the U.S. Department of Agriculture's Agricultural Research Service think that, over time, T. solenopsae can reduce fire ant populations.