TOKYO, Jan 13 (Reuters) - Japan said on Saturday it had confirmed a case of bird flu at a poultry farm in southwestern Japan but could not immediately determine if the outbreak was due to a highly pathogenic strain of the virus. Some 3,800 chickens have died on the farm in Miyazaki prefecture since Wednesday, an outbreak that if confirmed as due to the lethal H5N1 strain, would be the first in Japan since 2004. There were no reports of human infections. A Miyazaki prefectural official said that tests showed that the chickens were infected with an H5 subtype of the virus, but further testing was needed to determine whether the virus had the N1 component that would make it the highly pathogenic H5N1 strain or the less lethal H5N2. Local authorities have independently from Saturday started sterilising areas near the poultry farm, another official at the Miyazaki government's livestock section said. Miyazaki on Japan's southernmost main island of Kyushu is the country's top breeder of chickens, local authorities say. As of Feb 1, 2006, the number of chickens that it was raising for meat was 18.4 million birds. Between January and March in 2004, Japan had four outbreaks of the H5N1 type strain in poultry, including an outbreak in Kyoto in western Japan in February 2004 that led to the disposal of about 240,000 chickens and 20 million eggs. A less virulent strain of bird flu, caused by the H5N2 virus, was found in a poultry farm in Ibaraki prefecture in June 2005, and since then, there have been outbreaks of the weaker strain at 41 farms, the last one in January 2006.
