Abstract
Edward Harrison (1759-1838) was an English doctor best known for his ground-breaking treatments of spinal deformities and his failed attempts at medical reforms in the early 19th century. However, with the encouragement of his patient and patron Sir Joseph Banks, he also undertook comparative research on the influence of environmental factors on infectious diseases of medical and veterinary importance using approaches that were forerunners of the modern-day concepts of EcoHealth and One Health. His works in this field, particularly his study of sheep rot, are highlighted.