Gaspard Vieusseux (February 18, 1746 – October 21, 1814) was a Genevan physician born in Geneva.
In 1766 he obtained his doctorate from the University of Leiden, and subsequently returned to Geneva in order to practice medicine.
Vieusseux is remembered for his pioneer work with neurological disorders.
In 1806 he provided an early clinical description of bacterial meningitis — this being in regards to an 1805 epidemic of the disease in the vicinity of Geneva.
However, this disease was later to become known as "Wallenberg's syndrome", named after neurologist Adolf Wallenberg (1862–1949), who in 1901 provided a precise anatomical description of the disorder from an autopsy.
Vieusseux also distinguished himself as an early advocate of vaccinations for treatment against smallpox.