China lifted a bird flu quarantine in southwestern Guizhou Province on Tuesday after no new cases were reported in the past 21 days.

No new outbreaks of the deadly H5N1 bird flu virus strain have been recorded in the past three weeks after at least 240,000 poultry were slaughtered following an outbreak on February 17 in Zheng'an county, Zunyi City in Guizhou, the Ministry of Agriculture said.

The ministry has urged local authorities to beef up supervision and prevention measures and raise people's awareness to prevent new outbreaks.

Bird flu, or Avian influenza, is a contagious disease of animal origin caused by viruses that normally infect only birds and, less commonly, pigs. It can kill humans.

Five bird flu outbreaks in poultry have been recorded in China this year. Others included one in Xinjiang Uygur Autonomous Region, two in the southwestern Tibet Autonomous Region and one in the southern Guangdong Province.

On February 25, a 44-year-old Guangdong woman surnamed Zhang was killed by the H5N1 strain of the bird flu virus. Her death raised the total number of human bird flu cases recorded in China to 29, of which 19 have been fatal, according to the World Health Organization.

(Xinhua News Agency March 19, 2008)