The sister of a Vietnamese bird flu patient died in hospital last week, health officials said Thursday, while denying the virus was to blame, even though no tests were carried out before she was buried.
Authorities earlier this week reported Vietnam's first human case of bird flu since early last year, saying tests had shown the eight-year-old girl had contracted the H5N1 virus and adding that she was recovering well.
On Thursday, several state newspapers reported that the girl's 13-year-old sister had died last Friday, just days after both girls had eaten poultry dishes in their family home in northern Thanh Hoa province.
When contacted by AFP, a provincial health official ruled out the possibility that avian influenza had caused the 13-year-old sister's death.
The elder girl "had an infection and diarrhoea, not like bird flu," said Nguyen Ngoc Thanh, acting director of the provincial health department. "We did not take her samples for tests, and we will not."
State media reports said the family of the two girls had prepared and eaten chicken and duck dishes some days before they both fell ill.
Vietnam's national animal health department confirmed a bird flu outbreak in poultry near the girls' house, but only after the human case was reported.
Truong Thi Mau, director of the Ba Thuoc district hospital, told AFP that the 13-year-old sister was hospitalised on the night of Wednesday, December 31 and died two days later in the intensive care section.
"Her symptoms were a stomach ache, very high fever and diarrhoea," said Mau. "We suspected she had malaria or dengue fever ... We did not think of bird flu because we haven't had bird flu outbreaks in our area for some time."
According to the World Health Organisation, initial symptoms of bird flu include a high fever and influenza-like symptoms while other early signs of the virus include diarrhoea, vomiting and abdominal and chest pain.
"I don't know about whether the preventive health care workers will take her samples for testing because the family has already buried her body. But when she died, we did not take a blood sample for further testing," said Mau.
The eight-year-old girl was only admitted to a district hospital after her elder sister had died and was quickly taken to a larger provincial hospital after an X-ray showed damage to her lungs, she said.
A third child - a five-year-old boy living next door to the girls' family who had also eaten chicken and duck dishes - was being treated for respiratory symptoms in the district hospital, said Mau.
"However, he had only normal pneumonia and we received an answer from the provincial level that he is negative for bird flu," she added. "He will be discharged from hospital today as he is OK now."
The virulent H5N1 viral strain killed five people in Vietnam in early 2008, but no new human deaths have been reported since last March.
The World Health Organisation has since 2003 confirmed 393 human cases of bird flu, not including the latest Vietnam case, of whom 248 have died.
Vietnam has confirmed 52 bird flu deaths, the second highest toll after Indonesia, where the virus has killed 113 people.
Bird flu mainly kills animals, but scientists fear it could mutate to jump easily from human to human, potentially sparking a global pandemic.