求bird flu 的传播途径 （英文）

Bird Flu Spreads in Several Asian Countries

Katherine Maria

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 h