When it comes to dangerous ant pests in the United States, most people are concerned with the red-imported fire ant, and maybe the less common black-imported fire ant. These two medically significant ant pests mate and produce equally dangerous hybrids in areas where both of these ant pests have established an invasive habitat. Luckily, area-wide pest control programs have managed to halt the spread of both of these ant species in the US, and today, these ant pests are only a threat to residents living in the southeastern region of the country. The European red ant is widely considered to be the only ant species in the northeast that can inflict medically significant stings to humans, but case reports have found that a little-known species, Hypoponera punctatissima, inflicts painful stings to humans that can induce serious allergic reactions, including anaphylactic shock, which can be fatal.

Hypoponera punctatissima is sometimes referred to as “Roger’s ant,” and although this species is native to Asia, researchers believe that this species is one of the most widely distributed ant species in the world. In the US, Roger’s ant has become established in Florida, but these ants are also known to inhabit homes and buildings in the northeast. The climate in the northeast is too cold for this species to establish outdoor colonies, but colonies have become established in structures, around compost piles and near heat sources within human dwellings in the northeastern states. Several medically significant incidents involving these ants swarming within structures have been documented in the northeast. For example, back in 1992, a health care facility in the northeast had to be evacuated after these ants swarmed the structure. This incident saw patients and one nurse sustain stings, which caused the nurse to develop shortness of breath, wheezing and anaphylactic shock. The nurse later recovered from the stings.

Two other swarming incidents within structures in the northeast saw sting victims develop identical symptoms, and the ants had been observed swarming from the soil beneath concrete slabs in all three of the documented incidents. To this day, not much is known about this species’ unique pest behavior in the northeast, but most sources state that these ants sometimes inflict stings after they become trapped in sweaty human clothing while swarming. These tiny elongated ants are yellowish-brown in color, and swarms are known to suddenly emerge in structures during the summer in the northeast.

Have you ever sustained painful ant stings while indoors?