GENEVA (Reuters) - H1N1 swine flu is on the rise in China and Japan after triggering an unusually early start to the winter influenza season in Europe, Central Asia and North America, the World Health Organization said on Friday. According to the U.N. agency's latest official toll, which is thought to underestimate the total spread of the virus, at least 6,071 people worldwide have died as a result of an H1N1 infection since its discovery earlier this year in Mexico and the United States. Some 359 deaths were recorded in the past week, which saw a big outbreak in Ukraine as well as ongoing spread of the virus across the northern hemisphere. "Intense and persistent influenza transmission continues to be reported in North America without...