Updated

China and Vietnam on Friday each confirmed new bird flu (search) outbreaks, while Japanese authorities said 180,000 chickens would be killed after signs of the virus were found at a farm.

Adding to global jitters about bird flu, the Asian Development Bank (search) warned in a report that a flu pandemic could kill up to 3 million people in Asia, cost the region billions and plunge the world into recession.

China's latest outbreak — the fourth in the past three weeks in the world's most populous country — killed 8,940 chickens on Oct. 26 in Badaohao village in Liaoning (search) province east of Beijing, the official Xinhua News Agency (search) reported Friday, citing the Agriculture Ministry.

The outbreak prompted authorities destroy 369,900 other birds in the region, Xinhua said, and came despite efforts to tighten controls on China's 5.2 billion chickens, ducks and other poultry.

Hong Kong immediately banned poultry imports from Liaoning, reflecting growing concern that China is becoming a potential bird flu flashpoint.

Beijing (search) created an anti-flu task force this week and a $250 million fund to pay for anti-disease work. In the latest anti-bird flu measure, Beijing ordered hospitals to report data on flu cases daily to the government, Xinhua said.

No human cases have been reported in China, but authorities warn one is inevitable if the government can't stop repeated outbreaks in poultry.

In Vietnam (search), more than 3,000 poultry died or culled this week in three villages in Bac Giang province, about 35 miles northeast of Hanoi, provincial vice chairman Nguyen Dang Khoa said.

Transporting poultry to or from the three villages was banned, and the towns and those around them have been disinfected and remaining poultry vaccinated, he said. In one of the villages, Van Trung, about a dozen local officials on Friday went from house to house, beating to death any poultry they found.

"We expect more outbreaks, not just in Bac Giang, but also in other provinces," said another official, Hoang Van Nam, deputy director of the Animal Health Department. "Cooler weather now makes it easier for the virus to spread."

In Japan (search), authorities said antibody testing had found that 80 chickens at a farm in Ibaraki state had been exposed to a virus of the H5 strain, but survived. Nevertheless, 180,000 or 300,000 birds at the farm would be culled as a precaution, livestock officials said. About 1.5 million birds have already been killed in the state after finding signs of the disease at other farms.

The deadly H5N1 (search) strain of bird flu has killed at least 62 people — including 41 in Vietnam — and resulted in the deaths of more than 100 million birds in Asia since 2003.

Most human cases have been traced to direct contact with sick birds, but experts worry the virus could mutate and become easily transmissible between humans, possibly triggering a deadly flu pandemic.

In Thailand (search), the head of the state drug production company said Friday the country could begin as early as February distributing its own generic version of Oseltamivir (search), considered to be one of the most effective anti-viral drug to treat bird flu.

Swiss pharmaceutical company Roche developed Oseltamivir, known by the trademarked name Tamiflu (search), but cannot keep up with demand from countries trying to stockpile the drug.

Roche confirmed Tamiflu is not patented in Thailand and the country could manufacture it without compensating the company. It also offered Thailand its expertise in making the drug, saying it was "interested in ensuring the best possible global preparedness for a potential pandemic threat."

Underscoring the shortage, Cambodia's Health Ministry said it only enough Tamiflu to treat about 100 people.

In a report released Thursday, the Asian Development Bank outlined a number of scenarios the region could face in the event of a global flu outbreak.

In a worst-case scenario, the bank said Asia could lose almost $282.7 billion — or 6.5 percent of its gross domestic product — in consumption, trade and investment and another $14.2 billion due to workers' incapacity and death.

The report said "growth in Asia would virtually stop," and the economic impact would likely force the world into a recession. That scenario assumes about 20 percent of Asia's population would fall ill, and 0.5 percent would die.

China, Hong Kong, Singapore, Malaysia and Thailand would likely be hit hardest by the pandemic, the bank predicted.

A separate report by the World Bank said a human pandemic triggered by bird flu could cost the world economy as much as US$800 billion.

Meanwhile, U.N. Secretary-General Kofi Annan (search) urged governments to create better systems for compensating farmers with infected poultry stocks.

"If they are not compensated, they are not going to tell you whether their birds are sick," Annan said in New York. "If other pandemics have taught us anything, it is that silence is deadly."

In Australia, a man who returned from China complaining of shortness of breath was tested for bird flu and came up negative, a health official said.