A World Health Organization laboratory test has confirmed a 5-year-old Indonesian boy who died last month was infected with bird flu, a health ministry official said on Monday.

His death takes the total number of confirmed bird flu fatalities in the country to 40.

The victim died on June 16 in Tulungagung in East Java province after being admitted to hospital on June 8, I Nyoman Kandun, director general for communicable disease control at the health ministry, told Reuters.

The infection was confirmed to be from the H5N1 avian virus by a WHO laboratory in Hong Kong, he said.

An official at the health ministry´s bird flu center who declined to be identified said: "There was a dead chicken near his house."

The chicken cage was 15 meters (49 ft) from the boy´s home, the official added.