Chinese officials are racing to contain the spread of a new strain of avian flu that has infected at least 24 people and left seven dead.
Four hundred labs and 500 hospitals in the country are on the lookout for the latest virus.
Poultry markets in three cities have been closed.
The H7N9 influenza has been found in pigeons, but new cases have been found in humans.
Officials in Shanghai and three nearby provinces in central-eastern China are working on a bird flu vaccine.
Pigeon enthusiasts in China plan to vaccinate up to 90,000 and birds to help ward off the spread of the flu.