A 29-year-old man has been infected with bird flu in the sixth case in China in just three weeks, state media said Sunday, sparking fears of an outbreak as the nation celebrates the Lunar New Year. The patient, surnamed Zhou, fell ill on January 15 in the southwestern province of Guizhou, the official Xinhua news agency reported, quoting local health authorities. He tested positive for the deadly H5N1 strain of the virus on Sunday, and was still in a critical condition, the report said. Zhou is the sixth person to have become infected with bird flu in three weeks. Four of those patients have died from H5N1.