The World Health Organization (searchappealed Saturday for urgent action by China against bird flu, a day after tests showed the virus has been in chickens in the region since at least April, easing fears of a human pandemic.

Asian governments, meanwhile, sought to reassure the public that the virus was under control and poultry was safe to consume if properly cooked.

The WHO called on China (search), the world's most populous country, to share more information about the disease, step up monitoring for possible human cases and take precautions so that workers mass slaughter of birds aren't accidentally infected.

The appeal came after the communist government on Friday announced confirmed cases in two central provinces, Hunan and Hubei. It said it was investigating suspected cases in three other regions, including Guangdong in the south, where SARS (search) is believed to have begun.

China's first confirmed case was found Tuesday in a duck in the southern region of Guangxi. The country has reported no human cases of the disease that has been found in 10 Asian countries. Eight people have died in Vietnam and two in Thailand.

The human cases have been traced to direct contact with infected birds. There has been no evidence of its spread from human to human or from eating cooked poultry.

"We have repeatedly said there is a brief window of opportunity to act within China," Dr. Julie Hall, a WHO official in Beijing, said in a statement. "This latest news strongly suggests that the window is getting smaller with each passing day."

On Friday, the U.N. health agency welcomed tests showing that bird flu has been in Asia since at least April, raising hopes that if the disease was to jump to humans on a large scale it would have done so already.

"If the virus has been around for so long, there may have been dozens, hundreds or thousands of exposures to humans and nothing has happened so far when it comes to genetic recombination. That's good news, absolutely," Klaus Stohr, WHO's chief flu scientist, said.

The disease has struck Asian economies hard, with tens of millions of chickens killed by the virus or destroyed to prevent its spread, and governments are keen to restore public confidence.

In Thailand, the world's fourth-largest chicken exporter, billionaire Prime Minister Thaksin Shinawatra pledged to pay $75,000 of his own money in compensation if anybody dies from eating well-cooked chicken products.

The European Union, Japan and other major markets have banned Thai chicken products.

Thaksin said Saturday in his weekly radio address that cooked chicken meat was "100 percent safe" and he would prove it by eating it at every opportunity. Thaksin later lunched at a KFC fast-food outlet.

China also tried to reassure foreign customers of its huge poultry industry, announcing tighter health controls on chickens, ducks and other birds from areas still allowed to export. State newspapers showed government workers in masks, gloves and head-to-toe protective suits spraying disinfectant on poultry farms.

Bans already have been placed on exports from six provinces, including Shanghai, Anhui and Guangdong on Friday, the official Xinhua News Agency said.

The WHO examination was done on samples from chicken carcasses from an unspecified Asian country that were taken in April for reasons unrelated to bird flu. When the disease broke out in Asia, the country sent the frozen samples to WHO to see if they were infected with the H5N1 bird flu strain.

Governments battling the disease are: China, Thailand, Vietnam, Indonesia, Cambodia, Japan, South Korea, Laos, Taiwan and Pakistan. However, the strain of bird flu striking Taiwan and Pakistan is different from the one hitting the other countries and is not considered a serious threat to humans.