Venomous and aggressive fire ants from abroad have been found in seven prefectures since the first discovery in late May in Amagasaki, Hyogo Prefecture, in cargo inside a freight container that had come through Kobe port from China. Both the national and local governments should not spare any efforts in preventing the species from propagating in Japan.

The reddish brown ants with a blackish-red belly, which originate in South America, range from 2.5 to 6 mm in length. They are known for a sting that can cause anaphylaxis, a severe allergic reaction, including breathing problems. A queen fire ant can lay some 2,000 eggs a day. There are no signs yet that fire ants have propagated in Japan. Once they do so, however, they could potentially cause damage to agriculture and animals, and affect people's lives.

As cross-border movements of people and goods increase in the age of globalization, the possibility is rising of harmful species invading Japan. Government authorities need to carry out thorough quarantine steps, including measures designed to prevent fire ants from making nests. A total of 68 ports in this country are destinations of regular freight container shipments from China and Taiwan, where fire ants are now widespread.