Researchers in the United States say they have genetically engineered a vaccine that protects mice from the deadly H5N1 strain of bird flu.
In a report published Thursday by a British medical journal The Lancet, researchers say the experimental vaccine uses a common cold virus or adenovirus engineered with bird flu DNA, to stimulate the body's defenses.
They say such a vaccine could offer broad protection against mutations of the bird flu virus.
Meanwhile, Indonesian officials say local tests show a 15-year-old boy died from the H5N1 strain. If confirmed by the World Health Organization, the teenager would be Indonesia's 15th known fatality from the virus.
In Hong Kong, health officials say preliminary tests show three people who came into contact with a chicken infected with bird flu do not have the disease.
Wednesday, officials in Hong Kong said two dead birds, a crested myna and the chicken, tested positive for the H5N1 strain.
Bird flu has killed 85 people since 2003.
Some information for this report provided by AFP and Reuters.