Subfamily Myrmicinae
Solenopsis spp. or “fire ants” are widely distributed (in both native and exotic ranges) (Figure 2) and associated with allergic reactions. Although the sting is less painful, compared to bee and wasp stings, a wheal and flare reaction usually develops at the sting site, often with a pathognomonic sterile pustule, which may scar. This pustule effect is thought to be due to venom alkaloids, which are more potent in S. invicta (red imported fire ant) and S. richteri (black imported fire ant), compared to other species. (e.g.S. xyloni (southern fire ant), S. aurea (desert fire ant),S. geminata (tropical fire ant)).32
Severe allergic reactions have been estimated in approximately 2% of patients seeking medical care for ant stings and, as of 1989, over 84 fatal cases had been reported in the US.33Solenopsis species are also an important cause of allergy in Asia34 and South America perhaps exacerbated by deforestation.32
Pogonomyrmex , a species native to the US & Mexico, is thought to have the most painful sting of North-American ants, and the most toxic of all insect venoms based on median lethal dose in mice. At least two deaths have been attributed to stings from this species.35