Jakarta – An 11-year-old boy who died this week has been confirmed as Indonesia's 50th human bird flu fatality.

The boy died on on Monday and test results from two laboratories confirmed he was infected with the H5N1 virus, Nadirin – a doctor at the national bird flu information centre – told AFP.

Tests from two laboratories are required for the World Health Organisation to count the fatality in its toll.

Nadirin said that the latest death brought the number of confirmed deaths to 50, the highest reported anywhere in the world.

The boy, identified only by the initial A., came from Karanggentong in densely-populated East Java and had come into contact with sick poultry, the usual method of transmission of the virus, the doctor said Friday. He had developed a fever, cough and breathing difficulties two days before he died, the doctor added.

Indonesia's death toll from bird flu has been steadily rising as the virus has marched across the archipelago nation, spreading to 29 of its 33 provinces. While the virus does not spread easily among people, the chance of a mutation that would allow it to do so is heightened as more humans catch it from infected birds. Scientists fear that if this occurs, a global flu pandemic with a massive death toll could result.