Invasive Asian Needle Ant Threatens Health and Forests Across 19 U.S. States

A tiny invader from Asia, the Asian needle ant, is causing big trouble across 19 U.S. states, delivering stings that have landed people in hospitals and disrupting ecosystems. Originally hitching a ride to America in the 1930s, this ant went unnoticed for decades, quietly spreading from the Southeast to as far as Washington state.

Dan Suiter, a Georgia-based entomologist, describes the ant as a 'hidden critter' lurking in leaf litter and shaded forests. Its sting, which sent three people into anaphylactic shock last year, is no small matter. 'The pain comes and goes, sometimes returning days later,' Suiter notes, adding that emergency rooms may be seeing more cases than reported, misdiagnosed as mystery ailments.

Unlike your typical trail-following ants, this solitary predator roams alone, nesting under logs or mulch near homes. Its invasion threatens native ant species, which are vital for seed dispersal, and could stunt the growth of native plants in American forests. For those hypersensitive to stings, the risk is even higher, with experts urging anyone stung to collect the ant for medical identification.

If you spot a lone ant wandering aimlessly in your yard, don’t ignore it—it might be this invasive pest. Contact your local county extension agent to confirm and take action.