The United Nations health agency has confirmed a fourth bird flu death in Vietnam, and says an increased number of patients are seeking treatment for flu-like symptoms in the country's capital. Bird flu has been spreading rapidly among chickens in several Asian countries.
The World Health Organization says all four confirmed cases of bird flu in humans in Vietnam have been fatal. On Saturday the agency confirmed that the H5N1, or bird flu, virus, was found in samples taken from a five-year-old boy who died January 8.
Bob Dietz is the spokesman for a team of WHO experts investigating the outbreak in Vietnam.
"We do have one more confirmed case of H5N1," he said. "This was confirmed using lab results from within Vietnam."
Bird flu has been detected in poultry farms across Vietnam, Taiwan, Japan and South Korea, and millions of chickens have died or been killed in recent days.
But all reports of confirmed and suspected cases in humans have been concentrated in Vietnam, where health officials and doctors have reported a steady increase in suspected cases each day.
Mr. Dietz says there is also a noticeable rise in the number of people seeking treatment for flu-like symptoms in two Hanoi hospitals.
"We are seeing an increased number of respiratory illness cases," said Bob Dietz. "We don't known whether that's because there is more respiratory illness, or it's because cases are being referred to these two large significant hospitals."
The first three confirmed cases were discovered in Hanoi, but the latest victim lived about 100 kilometers south of the capital city in Nam Dinh province.
Mr. Dietz says millions of chickens in Vietnam alone have been slaughtered in efforts to contain the disease's spread.
The first known cases of bird flu in humans were reported in 1997 in Hong Kong. Six of the 18 people infected then died of the disease.
U.N. scientists say the bird flu virus currently affecting Vietnam has not begun to spread between humans. They suggest the victims caught the disease directly from chickens.
The emergence of bird flu in the region comes as health experts in China prepare for a fresh outbreak of Severe Acute Respiratory Syndrome in the country's south.
There, three people have been confirmed to have SARS, but experts are unsure how they caught the disease. Unlike bird flu, SARS can spread between people who are in close and sustained contact.