Jacques Fellay (born 12 August 1974) is a Swiss medical doctor and researcher active in the fields of human genomics and infectious diseases.

He is an associate professor at the École Polytechnique Fédérale de Lausanne, where he leads the laboratory of Human Genomics of Infection and Immunity.

He was clinically trained in infectious diseases in Switzerland, before spending 4 years as a research scientist at Duke University.

At the crossroad between basic biomedical science and the clinical world, his research aims at identifying the genomic factors modulating the human response to infectious and immune diseases, with the ultimate goal of offering novel diagnostic, preventative or therapeutic solutions customized to the unique genetic background of every patient.

[7] His publications have led to the identification of genetic factors influencing host control and therapy response to viral infections such as HIV, Hepatitis C or respiratory diseases.