Poultry vaccinations will ensure that bird-flu outbreaks this year will be fewer than in previous years, the country's chief veterinary officer has said.

There were more than 80 outbreaks of the deadly H5N1 virus in 2004 and 2005 but "as long as we stick to the vaccination program, we will dramatically reduce the likelihood of bird-flu outbreaks this year," Jia Youling said on Saturday.

As spring arrives and migratory birds fly north to their summer nesting grounds, Jia urged veterinary workers to continue with the "compulsory vaccination drive" throughout the country.

"China's experience has shown that vaccination is a very effective way to control bird flu," said Jia, also chief of the Veterinary Bureau under the Ministry of Agriculture.

Thanks to the unprecedented vaccination campaign, the mainland reported 32 outbreaks last year, compared with 50 in 2004, he told a press meeting.

Most of the 32 cases were in areas where vaccines were not properly administered, he added.

The three outbreaks reported this year also occurred in regions where vaccination efforts failed to meet standards, he said.

But the incidence is far lower than in the first three months of 2004, when 49 cases were detected throughout the country, he said.

Moreover, poultry farms which vaccinated their birds with ministry-approved vaccines have not seen any outbreak, Jia said.

The vaccination program has won support from international organizations, including the World Health Organization and the World Organization for Animal Health, he said.

Jia strongly refuted some media reports that vaccinated chickens may carry the bird-flu virus without showing any symptoms.

"So far there has been no confirmed case of a healthy, live chicken being a carrier of the virus," he said.

China's neighbors, such as Viet Nam, are using China-made vaccines, Jia said.

"We have been using Chinese vaccines nationwide and there has been no problem regarding quality," Hoang Van Nam, deputy director of the Animal Health Department in Viet Nam's Agriculture Ministry, was quoted by Reuters as saying over the weekend.

"We have just completed tests of 20,000 poultry nationwide and found no trace of bird flu," the official said.

Vaccines used on the Chinese mainland include one that can effectively guard waterfowl from H5N1, and the world's first live vaccine developed by Chinese scientists against both bird flu and Newcastle disease two killer infections for poultry, according to Jia.

"Our vaccines are the most effective in the world," Jia told China Daily.

By Friday, the ministry had apportioned 2.967 billion vaccines to local departments. Most of the areas will be well prepared by the time migratory birds fly north in mid-April, Jia said.

Meanwhile, China is closely monitoring mutations of bird flu and is ready to make new vaccines to cope with possible major mutations, he said.

Confident as he was in the efficacy of vaccines, Jia said he was worried that not all poultry raised in backyard farms would be vaccinated.

The ministry has dispatched 28 inspection teams throughout the mainland to see if bird-flu prevention and control measures are in place, specially in rural household poultry farms, he said.

(China Daily March 20, 2006)