By Adam Cailler & Benedict Tetzlaff-Deas The World Health Organization (WHO) has issued an urgent warning after a man contracted a potentially deadly form of swine flu. WHO officials confirmed the case on January 29, which was labelled as an “outbreak”. It was also claimed that that the case could have the “potential for high public health impact”. This is the third person to contract swine-origin influenza A, also known as swine flu, since 2008. A WHO spokesman said: “WHO continues to stress the importance of global surveillance to detect virological, epidemiological and clinical changes asso…