A human flu pandemic could cancel out a year of growth in Asia

If bird flu mutates to humans, it could cut Asia's economic output by as much as $300bn (�170bn), the Bank said.

"At its worst, this would essentially halt economic growth for one year and throw the world into the first global recession since 1982," ADB said.

Bird flu has so far killed about 100 people across Asia.

'Severe impact'

The Bank stressed that its analysis was based on a worst-case scenario in which between two and seven million people died during a pandemic.

The economic impact of such an outcome would be "severe", with key sectors of the economy such as tourism and banking badly disrupted.

Poor countries in Asia would face immense challenges Asian Development Bank Bird flu: country-by-country preparations

Its report echoes a recent study by the World Bank which said that bird flu could cast a "long shadow" over Asian economic prospects.

According to the ADB, poorer countries would be hard pressed to deal with the pressure on their health systems and welfare services.

In commercial terms, countries with large services sectors such as Hong Kong, China and Singapore would be worst affected and the fall in economic activity could have a devastating effect on global trade.

Based on current assumptions, however, the economic fallout from a human flu pandemic would not last long.

After the 2003 Sars outbreak, Asian economies recovered relatively quickly, and the ADB believes the turnaround from a bird flu pandemic would follow the same pattern.

"Economic activity would likely return to "normal" within one year and reach pre-pandemic levels in two to three years," the Bank noted in its 2006 Economic Outlook - a survey of 43 developing countries in the region excluding Japan.

Bird flu is already estimated to have cost Asian countries up to $15bn in lost economic output, with the poultry trade severely curtailed.

Sustained growth

Should a pandemic not occur, developing Asian economies are forecast to deliver strong growth this year.

Average growth of 7.2% is expected across the region, slightly down from the 7.4% seen last year, with both the Chinese and Indian economies cooling slightly.

China is expected to record 9.5% growth in 2006 with the Indian economy expanding 7.6%.

"Asia is well-positioned for sustained growth over the medium-term," said Ifzal Ali, the Manila-based body's chief economist.