Abstract
An eclectic, versatile Tuscan doctor, Eusebio Giacinto Valli (1755-1816) was a scholar of several branches of medicine, particularly public health, preventive medicine and epidemiology. His brilliant and wide-ranging education, and his intense passion for physics and chemistry, as applied to the human body, enabled him to conduct numerous studies in the field of vaccinology. He travelled to the Middle East in order to study the epidemiology of the plague and carried out experiments aimed at discovering a cure and a prophylaxis for rabies, succeeding in attenuating the rabies virus by inoculating a mixture of saliva from rabid dogs and gastric juice from frogs. Having travelled to Spain and then to Cuba, where he undertook the study of yellow fever, he died in Havana in September 1816, after injecting attenuated germs of the disease into his own body. He was buried in the great Monumental Cemetery "Cristobal Colon", where his tomb bears the epigraph: "victima de su amor à la humanidad ("a victim of his love for humanity").