Swine flu pandemic declared
Updated on 11 June 2009
The World Heath Organisation declares a global pandemic as swine flu sweeps the world on a scale not seen for 40 years.
The alert has been raised to the highest possible level after more than 28,000 cases of the illness in several continents.
The WHO delayed the announcement as long as possible, fearing it would spark widespread panic.
The last global flu pandemic was in 1968 and killed around one million people worldwide.
So far, swine flu has remained a relatively minor illness. But for how long?
Jon Snow was joined by the government's chief medical officer, Sir Liam Donaldson, to discuss the pandemic.
