Incubating farm outside Hanoi

7 September 2011 12:48 pm

Ducklings are pictured at an incubating farm outside Hanoi September 7, 2011.  Virologists warned on Tuesday that there was no vaccine against a mutant strain of H5N1 bird flu now spreading in China and Vietnam and called for closer monitoring of the disease in poultry and wild birds to stop it spreading to people. REUTERS