The northern mountainous province of Cao Bang on Nov. 22 announced bird flu outbreaks, according to the Department of Animal Health on Wednesday.

The department under Vietnam's Ministry of Agriculture and Rural Development said 12 chickens raised by three households in two wards of the province's Cao Bang town died on Nov. 13. Tests have shown that the fowls were infected with bird flu virus strainH5.

A total of 20 localities nationwide have detected poultry deaths since Oct. 1. However, recent tests have showed that fowls in southern Dong Thap province are not infected with bird flu viruses. Fowl deaths have been recently found in Dong Trieu district of northern Quang Ninh province, but testing results have yet to come out.

Hanoi capital and southern Bac Lieu province have met criteria for announcing an end to bird flu outbreaks (detecting no new affected spots for at least three weeks). Therefore, the current number of bird flu-hit localities, all in the northern and centralregions, is only 16, the department said, noting that they are BacGiang, Quang Nam, Thanh Hoa, Hai Duong, Hung Yen, Ninh Binh, Hai Phong, Quang Ngai, Vinh Phuc, Bac Ninh, Son La, Hoa Binh, Thai Binh, Phu Tho, Thai Nguyen and Cao Bang.

Since early last month, Vietnam has culled nearly 1.1 million fowls. The fowls were not only infected ones but also healthy ones, because Hanoi, Ho Chi Minh City and central Da Nang city have decided to stop raising poultry in their inner areas this month.

Vietnam is actively vaccinating fowls nationwide against bird flu viruses. Over 152 million poultry turns (each dose for a fowl being considered one turn, two doses for the same fowl regarded as two turns) have been vaccinated so far, the department said.

Previous outbreaks starting in December 2003 killed and led to the forced culling of some 46.6 million fowls in Vietnam, causing losses of 3.5 trillion VND (221.5 million dollars).