China has confirmed its first case of swine flu, with health officials in Chengdu saying a local man named Bao has tested positive.

He recently flew back to Sichuan Province from the United States and more than 130 passengers from his flight are now in quarantine.

Bao, 30, is being treated at Chengdu Infectious Disease Hospital and is reportedly in a reasonable condition.

The man took a Northwest Airlines flight from Minneapolis/St Paul, Minnesota, which stopped in Tokyo and landed at Beijing.

He also took a flight on Sichuan Airlines from Beijing to Chengdu.

Local media reports say the man developed flu-like symptoms on the flight from Beijing to Chengdu.

More hospitals are now being designated as centres to handle any widespread infection.

Chengdu's airport terminal is also being disinfected.

In the past Chinese authorities have been attacked for being too slow to respond to medical emergencies but this time the government is having to ward off criticism for being overzealous in its caution.

- ABC/Reuters