HANOI, Sept. 15 (Xinhuanet) -- Vietnam has just detected one more flock of ducks in Ho Chi Minh City being infected with bird flu virus, raising the total number of such kind of flocks in the cityto 35, a local veterinary official said on Wednesday.

    "Samples from the 35 flocks with a total of 34,900 ducks testedpositive for the virus strain of H5, but all of the fowls are healthy," said Phan Xuan Thao, deputy head of the Ho Chi Minh CityVeterinary Bureau.

    The infected ducks are found in four urban and rural districts,namely Cu Chi, Nha Be,Thu Duc and No. 9. However, the situation isgetting more complicated because some raisers have tried to sell the infected fowls to other districts.

    "A local farmer named Nguyen Van Liem in the district of Thu Duc sold 750 H5-positive ducks, which has forced us to keep track of them to take necessary preventive measures," Thao said, adding that to prevent the spread of the bird flu virus, the bureau has isolated the infected flocks, and persuaded farmers to have their fowls being culled.

    Now, 421 households in the city raise over 881,000 poultry, 53 percent of which are quails, 32 percent chickens and 15 percent ducks, he said.

    Vietnam´s Department of Animal Health under the Ministry of Health has recently announced bird flu either killed or led to theforced culling of 2,500 quails in the northern province of Hai Duong on Aug. 20, and around 100 chickens in the central province of Quang Tri on Aug. 19.

    Vietnam is strengthening anti-bird flu measures such as disinfecting farms, monitoring the transport and import of fowls and their eggs, and raising public awareness of the disease. Specifically, the ministry is distributing some 10 tons of postersand leaflets on ways of preventing and detecting bird flu to all localities.

    Since August 2004, Vietnam has discovered four human cases of H5 infection. These fatal cases have occurred amidst recurring H5N1 outbreaks in poultry in several Asian countries.

    In late March 2004, Vietnam declared an end to bird flu that had killed 17 percent of its poultry population, and claimed 16 human lives since its outbreak last December. A total of 43.2 million fowls nationwide either died or were culled, causing direct losses of 1.3 trillion Vietnamese dong (82.8 million US dollars) to the local poultry industry.