Authorities in Vietnam confirmed Saturday that bird flu has spread to two more provinces in the country.
That brings the total to four of Vietnam's 64 provinces where the H5N1 virus has been found in recent outbreaks.
Agriculture officials say the virus killed 250 young chickens in the southern Dong Thap province about a week ago. They report another 150 ducks and 35 chickens were sick with the virus on Wednesday in the northern Thai Nguyen province.
The virus had earlier been reported in the northern provinces of Dien Bien and Cao Bang.
The government says bird flu has killed four people in Vietnam this year, bringing the human death toll in the country to 46 since the first outbreak of the virus in 2003.
Some information for this report provided by AFP and Reuters.