South Korean health authorities reported Saturday that it has confirmed an American resident infected with the new type-A influenza virus.
It is the fifth case of the virus confirmed in the nation, local media said.
The 23-year-old female English teacher has been quarantined and is going through a close examination at a local hospital, according to health authorities.
"We are currently trying to find out how she was infected with the virus and tracking down the people she contacted during her stay in the country for other possible infections," an official at the Korea Centers for Disease Control and Prevention (KCDC) said.
Since the first report of the A/H1N1 flu in Mexico last month, South Korean health authorities have confirmed five patients infected with the virus, including three Koreans and one Vietnamese traveler, all of whom were released from quarantine after being treated with antiviral drugs.