The spread of avian flu across Asia is raising alarms, considering that it comes on the heels of the severe acute respiratory syndrome, or SARS, outbreak last winter, which killed 800 people worldwide and sickened thousands before it was contained. A few new SARS cases -- none of which were fatal -- have been reported recently in China, Singapore and Taiwan.

In addition, the avian flu outbreak has different economic ramifications from those posed by SARS. Impoverished Chinese farmers often are reluctant to kill their chickens, particularly if the birds appear healthy, on what they see as the slim chance that the fowl was infected by a farm miles away. The potential for evasion and the smuggling of poultry out of infected areas are added risks, officials said.

Deng Hongkui, an expert at the life sciences college of Beijing University, said it is essential that Chinese provinces report cases quickly to stem the spread. But the Chinese leadership seems well aware of the potential danger of avian flu, he said, given its experience with SARS -- the nation came under severe domestic and global criticism for concealing the outbreak.