Sabin (left) and Gallo. Sabin served as a full-time expert consultant for the NCI in 1974. Gallo was a former Biomedical Researcher, NIH. Robert Charles Gallo (born March 23, 1937) is an American biomedical researcher, best known for his role in the discovery of HIV, the infectious agent responsible for AIDS, and a major contributor to subsequent HIV research. Assignment of responsibility for the discovery of HIV has been controversial. Gallo states that his choice of profession was influenced by the early death of his sister from leukemia, a disease to which he initially dedicated much of his research. Albert Bruce Sabin (August 26, 1906 - March 3, 1993) was an American medical researcher best known for having developed an oral polio vaccine. The Sabin vaccine consists of weakened forms of the viruses that cause polio. It protects the body against polio without causing the disease. The Sabin vaccine is easier to give than the earlier vaccine, developed by Jonas Salk in 1954, and its effects last longer. In 1983, Sabin developed calcification of the cervical spine, which caused paralysis and intense pain. This condition was successfully treated by surgery conducted at Johns Hopkins Hospital in 1992. He died a year later, from heart failure, at the age of 86. No photographer credited, August 1985.