Tishler, happy to be employed, subsumed himself in his first project: vitamin B2. Without its own drug leads, Merck had decided to manufacture vitamins, an uncommercialized field where the limitations were the very opposite of those during the flu pandemic. Here the cures were well known; the failure was that no one had found incentive to make them. Scientists had known for nearly twenty years that those deprived of even one- to two-thousandths of a gram daily of B2suffered an array of ailments: Their mouths cracked at the corners, their tongues swelled, their eyes hurt, their skin grew inflamed. Among starch-eating sharecroppers in the South, who didn’t get enough B2or a related vitamin, niacin, the suffering was extreme: skin lesions, wrenched bowels, depression, apathy, and the so-called three D’s (dermatitis, diarrhea, and dementia) of pellagra. Two years earlier, German and Swiss chemists had patented a method for making B2, but, seeing no market, had refused to license them in the United States.