China immunized some five billion domestic birds since October, pushing the poultry immunity density to over 85 percent, a senior official said here Wednesday.
   
Twenty-seven bird flu outbreaks hit China in the last three months with three in October, 23 in November and only one in December, said Li Changyou, deputy director of the Veterinary Bureau of the Agriculture Ministry.
   
It shows that bird flu is under control along with the increase of immunity density and that immunity has played an important role, Li said.
   
China expedited the process of developing bird flu vaccines to curb the outbreaks. A new vaccine that can prevent both bird flu and new castle disease is expected to be put into use shortly, he said.

(Xinhua News Agency December 22, 2005)