A 59-year-old farmer has died of bird flu in northeastern Thailand, bringing the death toll in the country from the deadly H5N1 virus this year to three, public health officials have said.

Kumnuan Ungchusak, director of the public health ministry´s epidemiology bureau, said the victim fell sick in mid-July and died on August 10 in Nong Bua Lam Phu, some 580 kilometers (360 miles) northeast of Bangkok.

"There were sick chickens at his house," the director said.

Another health ministry official also said the laboratory test had confirmed the man died of the H5N1 virus, adding: "He was believed to have been in contact with sick chickens."

Thailand is among the countries hardest hit by the deadly H5N1 virus, recording 25 human cases, 17 of them fatal, since the outbreak began here in 2004.

The latest bird flu fatality followed the death in July of a 27-year-old farmer in the central province of Uthai Thani. He died after burying a dead chicken with his bare hands.

Thailand was criticized for being slow to respond to the outbreak of bird flu, but now is considered one of the countries best prepared to battle the disease.

To help control the spread of the virus, 900,000 volunteers have been recruited across the country to spray disinfectant around poultry farms every three months and check for signs of illness among residents.

The kingdom aims to be completely free of the virus in three years.