South Korean farms hit

A highly infectious form of bird flu was discovered in a duck 90 kilometres south of Seoul in the fourth farm in South Korea to be hit with avian influenza in a month, the Agriculture Ministry said Friday.

More tests were required to see whether the latest case at a duck farm in Asan represented an infection with the H5N1 strain of bird flu, which has proven dangerous to people, a worker in the ministry's department of animal health said.

About 770,000 birds have already been culled in Iksan, south of Asan, after H5N1 infections were discovered at two poultry operations there. Another 365,000 birds were killed nearby in Gimje, also because of an H5N1 outbreak.

About 23,000 poultry are also to be killed in a 3-kilometre radius from the affected Asan farm. The Agriculture Ministry said bird flu also broke out on the duck farm in February 2004.

According to the UN's World Health Organization, 258 people have been infected with H5N1 in 10 countries in Asia and Africa since late 2003. Of them, 154 have died.

No human cases of the disease have been reported in South Korea, but from 2003 to 2004, a bird-flu outbreak among poultry there led to the killing of 5.3 million birds in an effort to stop the spread of the disease, which is virulent among poultry.

It's transmission to people is more difficult, and most human patients have contracted the disease through close contact with infected birds. Health experts fear, however, that the virus could mutate into a form that could spread from human to human.

© 2006 DPA