Invasive Ant Invasion: Nearly 20 US States Face Deadly Threat

Asian needle ants, an invasive species native to East Asia, have been confirmed in nearly 20 states across the United States, alarming experts due to their painful and sometimes deadly stings.

This species has established itself in the southeastern U.S. since 1932 but has seen a significant increase in its range in recent years. As of June 2025, Asian needle ants are reported in 19 states, with Texas suspected to have active populations. Confirmed locations stretch from the eastern seaboard, including Florida and Massachusetts, to as far inland as Arkansas and Wisconsin. Washington is the only state on the west coast with documented sightings.

The sting of an Asian needle ant can lead to severe reactions, including hives, difficulty breathing, and even anaphylactic shock. Although these ants are less aggressive than fire ants, they can still sting when threatened. According to NC State University, stings often occur when humans inadvertently disturb their nests.

Symptoms of an Asian needle ant sting vary widely. Individuals may experience skin reactions, respiratory issues, or gastrointestinal distress. Reports indicate that around 1% of those stung may go into anaphylaxis, heightening concerns for vulnerable populations, such as children and the elderly.

Identifying Asian needle ants can be challenging. Measuring just 0.2 inches long, they are shiny with a dark brown to black body and lighter orange-brown antennae and legs. Their nests may be found in forested areas or near homes, existing under mulch, rocks, and logs, as detailed by the U.S. Department of Agriculture.

Efforts to control the spread of this invasive species have been ongoing for the past two decades, with researchers targeting remote forest areas. For those in potential nesting zones, using protective clothing is highly recommended to mitigate the risk of stings.