Over 150 million birds had been given two shots each since the campaign began late July, Minister of Agriculture and Rural Development Cao Duc Phat told the meeting.

Over two thirds of the vaccinated fowls were chicken and the rest ducks, Hoang Van Nam, deputy director of the Animal Health Department, said.

There had been no thorough study on the effect of the vaccination, Nam admitted but said preliminary assessments showed no outbreaks among immunized flocks.

Vietnam has culled almost 4 million birds since the epidemic re-emerged in October 2005.

During the previous major outbreaks in 2004 and early 2005, it culled 43 million birds to halt the spread of the deadly H5N1 virus strain that has killed 70 people in Asia, including 42 in the country.

No new human case

The past 50 days saw no new bird flu infection in humans anywhere in the country, the National Committee for SARS and Bird Flu Prevention said at a regular sitting in Hanoi.

Representatives from the Animal Health Department said the central Nghe An province was declared free of bird flu since no new outbreaks had been reported over the previous 21 days, the mandatory waiting period.

Bird flu remained in only three provinces, Ha Giang and Cao Bang in the north, and Quang Tri in the center, the department said.

However, Vietnam would remain under threat for the next two months since cool weather was favorable for the spread of bird flu while the demand for poultry was high, Phat warned.

Source: Tuoi Tre, Vietnam News Agency – Translated by The Vinh