Up to 100 million people may die within weeks if a bird flu pandemic breaks out, a senior World Health Organisation (WHO) official warned on Monday as he urged nations to make urgent preparations to mitigate its spread. A global outbreak is almost certain and even widescale vaccination programmes will not be enough to halt its inexorable advance, the WHO director for the Western Pacific, Shigeru Omi, said in Hong Kong. "The most conservative estimate is that seven to 10 million people would die, but the maximum range will be more -- 50 million or even in the worst case...