Flu researchers plan to repeat controversial work

Having made H5N1 transmissible, scientists intend to do the same with H7N9

After stirring up controversy by creating airborne-transmissible versions of one deadly bird flu virus, scientists intend to do it again with another. This time, the experiments will involve H7N9, a new strain of avian influenza that infected 134 people in China this year, killing 43.