The outbreak was discovered on Monday at a farm with about 11,000 egg-laying chickens in Izumi City in Kagoshima prefecture in southwestern Japan, the ministry said in a statement on its website. reported Reuters.

The occurrence coincides with outbreaks in Europe and Asia that have been reported to the World Organisation for Animal Health (OIE) in the recent days. This is a sign that the virus is spreading quickly.

"The NA subtype of the highly pathogenic avian influenza virus was identified and it was confirmed to be H5N8 subtype," the ministry said.

The increase in the number of people around the world getting infected from bird flu this year is becoming a source of concern for epidemiological experts.

This year, China has reported 21 human infections with the H5N6 subtype of avian influenza to the World Health Organization. Six have died, and many are critically ill. Last year, the country reported just five cases of human infection.

In February, Russia registered the first case of the H5N8 strain being passed to humans from birds and reported the matter to the WHO. There was no sign at the time of transmission between humans.

Japan temporarily suspended exports of chicken meat and eggs from all regions earlier this month after reporting the first outbreak, though the ministry has said the consumption of those items, if infected, pose no risk to humans.

Last winter, Japan had its worst season of avian influenza on farms yet. Almost 10 million chickens were culled and more than a third of the country's prefectures affected.

Japan has an egg-laying flock of around 181 million hens and a broiler population of 140 million, according to the ministry of agriculture.