Medical officials in Vietnam say initial tests of a bird flu vaccine on monkeys have been successful.
Vietnamese researchers injected a vaccine based on weakened H5N1 bird flu virus on three monkeys early last month.
They say three weeks later the monkeys were healthy and had produced antibodies.
The director of the National Institute of Hygiene and Epidemiology, Nguyen Tran Hien, says further tests have been done and the results are expected in the next two weeks.
Vietnam’s state media reports researchers hope to have a vaccine for the virus ready for testing in humans later this year.
Fourteen people have died in Vietnam of the latest bird flu outbreak, which began in December.
Health experts last month said they feared a vaccine would have limited effect against the virus if it mutated into a form that could be transmitted between humans.