HANOI - A THREE-YEAR-OLD Vietnamese boy died on Thursday from bird flu, a doctor in southern Ho Chi Minh City said, becoming the country's third human victim of the disease this year.

Tran Cong Phuc was admitted to the city's Tropical Diseases Institute on Monday where he tested positive for the deadly H5N1 strain of the avian influenza virus.

His condition worsened on Thursday morning and he died in the afternoon, said the director of the institute, Nguyen Tran Chinh.

Communist Vietnam has the world's second-highest bird flu death toll after Indonesia, with 55 deaths.

Phuc's family raised chickens in the Mekong delta province of Dong Thap and local doctor Nguyen Thi Thu Huong said some of the birds had died earlier this month.

'His parents cooked soup with the meat from the dead chickens for the boy to eat,' Huong said, adding the boy's parents also ate chicken but showed no sign of illness. 'We are doing quarantine and cleansing the area around the boy's house.'

A doctor from the municipal Pasteur Institute said before the boy's death that his sample would be tested again to confirm the infection.

The H5N1 virus typically spreads from birds to humans via direct contact, but experts fear it could mutate into a form easily transmissible between humans, with the potential to kill millions in a pandemic.

Tran was the third person to have died from the H5N1 strain of bird flu in Vietnam this year, according to official figures. The two other had both slaughtered and eaten sick poultry before they died, Vietnam News Agency cited the Health Ministry's Preventive Medicine and Environment Department as saying.

The World Health Organisation (WHO) and the UN's Food and Agriculture Organisation (FAO) said last month that Vietnam had to monitor the bird flu situation closely to prevent more deaths.

'The message is: stay aware the virus is still out there and we must not be complacent,' Shelaye Boothey, WHO spokeswoman in Hanoi, said prior to the latest death.

According to the WHO, H5N1 has killed more than 250 people across the world since 2003. -- AFP