Born Oct. 5, 1879, in Baltimore; died Feb. 16, 1970, in New York. American pathologist. Member of the National Academy of Sciences of the USA and many other academies and scientific societies.

Rous graduated from the faculty of medicine of Johns Hopkins University. He worked at the Rockefeller Institute for Medical Research in New York from 1909 and in 1945 was named an honorary member. He was editor of the Journal of Experimental Medicine.

Rous’ major scientific contribution was the discovery of oncogenic viruses. In 1911 he demonstrated that sarcoma may be transferred from a sick to a healthy chicken not only by cells but also by cell-free filtrates of tumor tissue. The Rous sarcoma virus was subsequently identified and studied by many oncologists and virologists. It is currently widely used in oncovirologi-cal studies. Rous and his colleagues established that an organism’s mechanisms of immunity against an oncogenic virus differ from its mechanisms of immunity against a tumor cell infected by the virus. They also showed that the oncogenicity of oncogenic viruses increases when the viruses are used with either carcinogens or stimulators of cell growth. Rous also published many generalizing works on the role of viruses in the generation of tumors. He also proposed the concept of tumor progression. Rous was awarded the Nobel Prize in physiology and medicine in 1966.