The ORGANIZATION@1 says some NUMBER@1 billion people , two fifths of the world 's population , are now at risk from dengue and estimates that there may be NUMBER@2 million cases of dengue infection worldwide every year .

The ORGANIZATION@1 says some NUMBER@1 billion people , two fifths of the world 's population , are now at risk from dengue . Estimates are that there may be NUMBER@2 million cases of dengue infection worldwide each year .
