A UNIVERSAL flu vaccine has been successfully tested on humans with the disease for the first time, it was reported Monday. The U.K.s Guardian newspaper said that unlike existing vaccines, this one, which was tested by scientists at Britains Oxford University, does not need to be changed every year to match the latest strain of the virus. The Guardian said when a new strain of flu emerges it takes at least four months to develop a new vaccine, during which time people get sick and some die. In 1918, a particularly dangerous form of flu developed in Europe and then spread across the world, killing an estimated 50 million people, about 3 percent of the worlds population at the time. Dr. Sarah Gilbert, who led the Oxford research team, told The Guardian using the same vaccine every year would mean protecting against flu would be more like vaccinating against other diseases like tetanus. It would become a routine vaccination that would be manufactured and used all the time at a steady level. We wouldnt have these sudden demands or shortages - all that would stop, she added. The Guardian said Gilbert had infected 22 healthy volunteers with the Wisconsin strain of the H3N2 influenza A virus. Half had been given the new vaccine, the others had not. Fewer of the people who were vaccinated got flu than the people who werent vaccinated, she told the paper. She also said that T-cells, part of the bodys immune system, were more active in those who had been given the vaccine. The volunteers we vaccinated had T-cells that were activated, primed and ready to kill, Gilbert said. MSNBC