Bird flu detected in southern Japan identified as virulent H5N1 strain

Tests have confirmed that bird flu detected in chickens in southern Japan was the virulent H5N1 strain, the Japanese Agriculture Ministry said Tuesday.

About 4,000 chickens died last week at a farm in Kiyotake town in Miyazaki prefecture (state). Earlier test results Saturday only confirmed the bird flu strain was an H5 virus, but not which one.

On Tuesday, further tests by the National Institute of Animal Health near Tokyo identified the virus as H5N1, the virulent strain that has been blamed for more than 160 human deaths worldwide, Agricultural Ministry official Hiroyuki Ozono said.

The institute is still running tests for DNA analysis and more pathogenic details of the virus, including its strength, the ministry said later in a statement.

Miyazaki officials on Monday burned all the dead birds and 8,000 surviving chickens at the farm.

The government has banned the shipment of eggs and nearly 200,000 chickens at 16 farms within a 10-kilometer (6.2-mile) radius of the affected farm, where local authorities were to take further disinfectant measures Tuesday.

Since 2003, the H5N1 bird flu strain has killed at least 161 people worldwide, according to the World Health Organization. Japan has confirmed one human case, but reported no human deaths.

Miyazaki, about 900 kilometers (560 miles) southwest of Tokyo, is Japan's largest chicken producing region.