The world risks a repeat of the disastrous 2006 bird flu outbreaks unless surveillance and control of this and other dangerous animal diseases is strengthened globally, the Food and Agriculture Organisation (FAO) has warned.

"The continuing international economic downturn means less money is available for prevention of H5N1 bird flu and other threats of animal origin. This is not only true for international organisations but also countries themselves," says FAO Chief Veterinary Officer Juan Lubroth. "Even though everyone knows that prevention is better than cure, I am worried because in the current climate governments are unable to keep up their guard."

Continued strict vigilance is required, however, given that large reservoirs of the H5N1 virus still exist in some countries in Asia and the Middle East, in which the disease has become endemic. Without adequate controls, it could easily spread globally as it did at its peak in 2006, when 63 countries were affected, Nigeria inclusive.

Investing more in prevention makes economic sense given the huge toll inflicted by a full-scale pandemic. Between 2003 and 2011 the disease killed or forced the culling of more than 400 million domestic chickens and ducks and caused an estimated $20 billion of economic damage.