Hanoi - The older sister of Vietnam's first reported bird flu case for 2009 died in hospital last week, health officials said Thursday.
Bui Thi Thuong, 13, was hospitalized December 31 and died on January 2 at Ba Thuoc hospital in Thanh Hoa province, 150 kilometres south of Hanoi.
'When she was first hospitalized her fever was not high, just 38.5 degrees Celsius,' said Dr Truong Thi Mau, director of the Ba Thuoc district hospital. 'We didn't think of bird flu.'
'But her health became very bad around 8 pm on January 1. She had a high fever of 40 degrees Celsius and she couldn't breathe by herself. There was no medical waste sample to test, so we couldn't say for sure if she died of bird flu,' said Dr Mau.
Her eight-year-old sister, was admitted to hospital and diagnosed by health officials on January 3 as Vietnam's first human case of the H5N1 virus in 2009. She remains in hospital.
Local media has reported that both girls ate chicken and duck raised on their family's farm.
The H5N1 avian influenza virus, known as is most commonly found in poultry, but has killed 248 people worldwide.
Five people died from the virus in Vietnam in 2008, but no cases were reported after March.
A total of 52 people have died from the H5N1 virus in Vietnam, the second-highest toll after Indonesia.
Bird flu is most common in Vietnam's north, where temperatures are cool during winter, allowing a more hospitable environment for the virus. Vietnam's south remains warm year-round.