Arizona is home to three fire ant species that can inflict painful and medically significant stings to humans. These ant species include Solenopsis xyloni, Solenopsis amblychila and Solenopsis aurea. Solenopsis xyloni is the most commonly encountered fire ant species in southern Arizona, and they are commonly referred to as “southern fire ants.” Most medically significant fire ant encounters in Arizona involve the southern fire ant, but S. aurea has also been known to inflict stings that result in serious medical complications. For example, in July of 2018, a Tucson woman was found unconscious and covered in S. aurea ants within her car. The woman was quickly taken to a hospital where doctors found a large number of papular-pustular skin eruptions on her abdomen and thigh, and she had developed disseminated intravascular coagulation, which is a condition involving numerous blood clots that block blood flow to small vessels. This condition prevents clotting which results in excessive bleeding.
The fire ants that attacked this middle aged woman, S. aurea, are native to Arizona, and they are more commonly known as “golden fire ants.” Apparently, the woman sustained countless stings from these ants after falling asleep in her car. The woman’s severe blood-clotting condition was believed to have resulted from “hemolytic factors” within golden fire ant venom. Hemolysis the process by which old or imperfect red blood cells are discarded, but the ant’s venom sped up the process of hemolysis, resulting in a dangerous decrease in the woman’s red blood cell count. This explains why the woman was in a state of shock when she was recovered from the automobile. The identity of the ant species was confirmed by medical staff who managed to capture specimens, and the doctors evaluating the woman were surprised to find that her symptoms were similar to those resulting from red-imported fire ant stings. While medical literature goes into great detail about the symptomatology of invasive fire ant stings, very little information has been published about the negative medical reactions to native fire ant stings. Since both native and invasive fire ant species are constantly expanding their habitats, which leads to a greater number of medically significant fire ant envenomations, many medical professionals are making an effort to spread awareness about the risks of native fire ant stings and the symptoms that result.
Have you ever sustained a sting from any type of fire ant species?