Fears of the dangers posed by a human-borne strain of the Asia Bird Flu virus have risen after a Vietnamese man (21) tested positive for the condition.
Tests confirmed the man from Thai Binh province, 110 kilometres southeast of Hanoi, had the highly contagious H5N1 strain that has killed 13 people in Vietnam's latest outbreaks.
His 14-year-old sister was being tested for the virus after she fell ill with a severe fever.
"Now we are disinfecting his home area. It is not clear how he was infected, but during Tet people everywhere ate chickens," an official said, referring to the Lunar New Year holiday this month when poultry is traditionally served.
Bird flu experts meeting in Ho Chi Minh City say the virus, which has killed 46 people in Asia since it erupted at the end of 2003, is now endemic in parts of the region despite the slaughter of 140 million birds.
They no longer talk about eradicating the disease, but of containing it before it mutates into a form which can pass between humans and sets off a pandemic that could kill millions.
Vietnam, battling fresh outbreaks in 35 of its 64 provinces this year, has appealed for technical and financial help at the UN-sponsored meeting of scientists, animal health officials and donor governments and agencies.
Foreign donors have been criticised for an "alarming" lack of commitment to fighting a virus the World Health Organisation says poses the "gravest possible danger" to the world population.
They gave only $18 million last year, far below the $100 million needed to detect and react quickly to outbreaks.