At the start of a three-day UN conference in Kuala Lumpur on the bird flu virus, health and animal experts have called for mass vaccination of poultry to prevent bird flu from becoming a human pandemic.
They say the virus, which has killed 55 people in Asia this year, has tightened its grip on Asia and is still capable of springing major surprises.
At present the virus only appears to spread by the close association of humans and poultry.
Medical experts however have always feared it could mutate into a form which could easily pass among people, triggering a global pandemic.
Dr Shigeru Omi of the World Health Organisation (WHO), says that the virus continues to behave in ways that suggests it remains as unstable, unpredictable and versatile as ever, and says there is a need to be on a constant alert.
The meeting which is co-organised by the WHO, the Food and Agriculture Organisation and the World Organisation for Animal Health, is known by its French acronym OIE.
Dr Omi says that avian influenza poses the threat of a pandemic, especially after re-emerging in China where the virus killed 6 000 wild migratory birds last month in the remote Qinghai province.
Vietnam, last month alone, reported seven new human cases and is now "chronically infected", while Cambodia and possibly Indonesia have reported their first human cases.
Joseph Domenech, the FAO's chief veterinary officer, says the prevention of a human pandemic is dependent on efficient control of infection in animals.
The only way to control it is by imposing mass vaccination of poultry and speeding up efforts to develop new poultry vaccines.
He says birdflu is not just an Asian problem, and no poultry producing country is safe from the occurrence of the avian influenza as long as there are pockets of infections in Asia.