By Linda Elovitz Marshall, Author & Lisa Anchin, Illustrator. Discover the fascinating life of world-renowned scientist Jonas Salk, whose pioneering discoveries changed the world forever. Dr. Jonas Salk is one of the most celebrated doctors and medical researchers of the 20th century. The child of immigrants who never learned to speak English, Jonas was struck by the devastation he saw when the soldiers returned from battle after WWII. Determined to help, he worked to become a doctor and eventually joined the team that created the influenza vaccine. But Jonas wanted to do more. As polio ravaged the United States—even the president was not immune!—Jonas decided to lead the fight against this terrible disease. In 1952, Dr. Jonas Salk invented the polio vaccine, which nearly eliminated polio from this country. For the rest of his life, Dr. Salk continued to do groundbreaking medical research at the Salk Institute, leaving behind a legacy that continues to make the world a better place every day. For ages 4 and up.