Guillaume de Baillou is considered to be the first epidemiologist since Hippocrates, and is credited as the founder of modern epidemiology. He did extensive studies of epidemics that plagued Paris, and is additionally credited with providing the first clinical description of pertussis (whooping cough) in 1578. He also provided the first modern descriptions of rheumatism and arthritis of which he defined in the treatise Liber de Rheumatismo et Pleuritide dorsali.
