Delegates to the two-day meeting said the world is being much more cautious in preparing for the risk of human-to-human transmission of the deadly H5N1 virus, which could trigger a pandemic.
The meeting comes as the human death toll from the virus rises as the bug spreads to a greater geographical area.
Albert Osterhaus, of the Netherlands' National Influenza Centre and the Erasmus Medical Centre in Rotterdam, said the spectre of three flu pandemics in the last 90 years - in 1918, 1957 and 1968 - lurks in the wings.
"Is this going to happen again? The answer's 'yes'. Are we properly prepared? The answer's 'no'," said Mr Osterhaus.
Guenael Rodier, communicable diseases expert at the World Health Organisation, said the longer and the more widely the virus circulates among poultry, the bigger the risk that it could make the leap to humans.
In the past six to nine months, H5N1 has been reported among birds in more than 40 countries, adding to the risk that it has become endemic and even tougher to wipe out.
Milan Brahmbhatt, lead advisor in the East Asian region of the World Bank, said pandemic scenarios range from deaths in the tens of thousands to around 70 million, with estimated costs to global gross domestic product ranging from around 0.8 percent to five percent.
Since the virus resurfaced in 2003 after initially emerging in Hong Kong in 1997, there have been 228 human cases, 130 of them mortal, according to the latest WHO figures.
There were 41 deaths in all of 2005, but 54 in the first six months of 2006 alone. In 2003, just one country (Vietnam) reported a death; this rose to two in 2004, five in 2005 and seven so far in 2006.
Mr Osterhaus said Europe will set up its own task force on bird flu in September or October, working under the new European Centre for Disease Prevention and Control (ECDC) in Stockholm.
He pleaded for a global equivalent, saying there was still a disturbing lack of coordination between scientists, governments and international agencies but too many meetings with much talk and little action.
"There's not a pandemic of flu, there's a pandemic of flu meetings," he said.