The possibility of a major resurgence of Highly Pathogenic Avian Influenza H5N1 – also known as bird flu – has prompted the United Nation’s FAO (Food and Agriculture Organization) to advise health authorities around the world to step up surveillance and readiness. There are signs that a mutant strain of Bird Flu is making inroads in Asia and other parts of the world. The FAO describes current the risks to human health as “unpredictable”.

Out of 565 individuals who have been officially infected with the H5N1 virus since 2003, at least 331 died, says the World Health Organization (WHO). Cambodia has had 8 deaths so far this year, one in August 2011; every infected person died.

Over 400 million domestic poultry have had to be destroyed since 2003 because of H5N1. Experts say the economic damage exceeded $20 billion worldwide, before bird flu was supposedly eradicated from the majority of the 63 nations infected in 2006 (bird flu peak).

Even so, H5N1 continued to be endemic in six countries – Viet Nam, Indonesia, India, Egypt, China and Bangladesh.

The number of domestic and wild birds infected fell from 4000 in 2006 to 302 in 2008. However, over the last twenty-four months, numbers have been steadily rising. 800 cases were reported in 2010-2011.