A large variety of pathogens and nematodes also infect red imported fire ants. Pathogens include "Myrmecomyces annellisae", "Mattesia" spp., "Steinernema" spp., a mermithid nematode, "Vairimorpha invictae", which can be transmitted via live larvae and pupae and dead adults and "Tetradonema solenopsis", which can be fatal to a large portion of a colony. Individuals infected by "Metarhizium anisopliae" tend to perform trophallaxis more frequently and have an enhanced preference to quinine, an alkaloid substance. Phorid flies with "Kneallhazia solenopsae" can serve as vectors in transmitting the disease to the ants. Weakening the colony, infections from this disease are localised within the body fat, with spores only occurring in adult individuals. The mortality of an infected colony tends to be greater in contrast to those that are healthy. These ants are a host to "Conidiobolus", "Myrmicinosporidium durum," and "Beauveria bassiana", each of which are parasitic fungi. Infected individuals have spores all over their bodies and appear darker than usual. The toxicity from antimicrobial property of volatiles produced by the ants can significantly reduce the germination rate of "B. bassiana" within the colony.