The rapid spread of the highly infectious avian flu virus H5N1 has reached an “unprecedented” scale, wiping out hundreds of millions of birds worldwide and increasingly spilling over into mammals, the UN Food and Agriculture Organization (FAO) warned on Monday.

A United Nations food agency warned that the continued spread of the H5N1 bird flu virus is an unprecedented food security risk that requires a coordinated global response. In a briefing held on

A United Nations health agency has called the spread of H5N1 bird flu "unprecedented" and called on world leaders to coordinate a global response.