The United States is being invaded by stinging ants from Asia, NBC reports. The ant invasion is damaging not only properties but also harming Americans because the tiny insect's sting produces small welts that are surrounded by a rash, itches and hurts when scratched.

Over the past few years, residents have observed the attack of different types of ants at gardens

buildings

and homes.

Eleanor Spicer-Rice, an entomologist at the North Carolina State University, said that residents of the state routinely go to hospitals due to ant bites.

"They are reaching into a woodpile and getting stung by Asian needle ants and they don't know what it is and what is happening to them. They don't realize the Asian needle ants are here," NBC quoted Ms Spicer-Rice.

Although records said that the earliest ants invasion in the U.S. was in the 1920s, ant populations have grown much in the past 8 years and continue to spread across the country.

Prior to the Asian ants invasion, Argentinean ants also bugged the U.S. The Argentinean ants are known for their aggressive behaviour and even push other ants out of their territory.

But it seems the Argentinean ants met its match in Asian needle ants since Ms Spicer-Rice found that the former's population had gone down to 67 per cent from 99 per cent on the sites in her study area covering Raleigh while the latter's population grew to 32 per cent from 9 per cent.

She explained the fast spread of the Asian needle ant to its ability to tolerate cooler temperatures better than those from Argentina. Asian ants, which belong to the specie Pachycondyla chinensis, also are early risers while other ant species hibernate during winter time.

Their early start allows the Asian ants to build nests, find food sources and begin reproduction while other ants are still snoozing. The battle for supremacy indicates an ant-eat-ant world, said Ms Spicer-Rice who is preparing a paper on ant behaviour for publication.

Her paper may be fodder for future ants horror movies like The Nights the Ants Came!

However, the ants phenomenon could also reflect the human migration scene in the U.S. where Asian immigrants, especially Chinese, are doing well economically, beating U.S.-born residents as well as migrants from Latin American nations.