The deadly H5N1 bird flu virus was found in a wild swan in northern Japan, but no poultry in the area have been found to be sickened with the disease, a health official said yesterday.
The dead swan was found on April 24 on the northern island of Hokkaido, said a local official who spoke on condition of anonymity because he was not authorized to speak to the press.
Following the discovery, health authorities began inspecting five chicken farms within a 30km radius of where the infected swan was found.
No reports of sick poultry have been discovered so far on the five farms, which raise about 9,500 chickens in total, the official said.
H5N1 was also confirmed in dead swans in northeastern Akita Prefecture on April 29.
The virus remains hard for people to catch, but scientists worry it could mutate into a form that spreads more easily between humans, with the potential to kill millions worldwide.
At least 240 people have died from bird flu since 2003, according to the World Health Organization. Most human cases so far have been linked to contact with infected poultry.