Bruce Aylward
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WHO: World facing polio health emergency

5 May 2014 Last updated at 19:18 BST

The World Health Organization (WHO) has declared the spread of polio is an international public health emergency.

Outbreaks in Asia, Africa and Middle East are an "extraordinary event" needing a co-ordinated "international response", the agency says.

WHO Assistant Director General Bruce Aylward says "one of the deadliest diseases in history has the opportunity to resurge".