Hanoi (AsiaNews/Agencies) - Vietnam on Friday reported another bird flu death, bringing the human toll to 10 over the past month, officials said. A 32-year-old man from northern Phu Tho province died on Thursday after spending five days in the Bach Mai Hospital's tropical disease unit, the hospital doctor said on condition of anonymity.

Two girls - aged 13 and 10 - who have tested positive for bird flu in southern Vietnam, remain in a critical condition in hospital. The 13-year-old girl is the daughter of a woman aged 35 who died from bird flu on January 21. Investigations are under way to establish how they became infected. Meanwhile two other men, aged 66 and 30, from Hanoi and Hung Yen province respectively, tested positive for the H5N1 strain of the bird flu and remain in stable condition Friday, the doctor said.

Since the end of 2003, outbreaks of bird flu have killed 41 people in Asia - 30 in Vietnam. It has also led to the death or culling of millions of birds across Asia.

Most of the victims are believed to have caught the virus from infected poultry, but experts fear it could mutate into one that is easily passed between people, unleashing a global human flu pandemic that could kill millions. According to the World Health Organization, the virus might affect 30 per cent of the world's population.