Although hepatitis has been acknowledged in its basic form since ancient times, it became the subject of intense investigation during the 1940's when a mass of World War II soldiers fell victim to the virus' rage. British and American physicians, frustrated by the scourge and intent on discovering a cure, conducted experiments on children with Down's Syndrome and prisoners. These highly unethical experiments led to the isolation of the hepatitis virus, the discovery of its transmission through the bloodstream, and the development of the hepatitis B vaccine.