As long as the immunization policy is carried out properly, the possibilities for an outbreak of bird flu in many areas will be remarkably reduced, said Jia Youling, national chief veterinary officer, on Saturday in Beijing.

At a press conference held by the Ministry of Agriculture, Jia said the country has provided 2.967 billion vaccines to local departments to stem the spread of bird flu.

Most of the areas will be well prepared by the time migratory birds fly north in mid-April, Jia said.

At the same time, relevant departments are ready to make new vaccines to cope with any variants of the virus, he said, adding the vaccine that has been developed can prevent the current virus.

"The most crucial measure is that all fowls must be injected with the vaccine," he said.

Since China took such measures from October 2005, the spread of bird flu has been contained. Three outbreaks have been confirmed so far this year, 46 less than during the same period in 2004. The 35 cases reported in 2005 have all been controlled.

As the virus can easily spread during spring, the ministry has urged local departments to ensure the above measures are implemented, Jia said.

The ministry has sent 28 supervisory groups to different regions of the country to inspect their work, and the preparation is satisfactory, he said.