[3] Guido Baccelli spent almost his entire clinical and teaching life in the ancient, glorious but by that time decaying and unfit, mediaeval hospital of Santo Spirito in Saxia in Rome, between the Tiber and the Vatican City.
[5] He gave relevant contributions to the struggle against malaria which, at that time, was one of the main health and social problems of the recently reunited Kingdom of Italy and of its Capital town.
[6] Guido Baccelli successively welcomed in his clinic of Santo Spirito the two future Nobel Prizes Alphonse Laveran (in 1882) and Camillo Golgi (in 1893) who were looking for confirmations of their theories about the origin and evolution of malaria, in the Campagna Romana, then scourged by the disease during summer and autumn time.
[4] Baccelli was quite slow in accepting the anopheles as the sole vector in the transmission of the illness,[7] nevertheless he was a strong medical and political supporter of the Laws for the drainage of the Campagna Romana and the Pontine Marshes that - along with the free administration of quinine - significantly reduced the incidence of the disease in those areas.
[10] Baccelli was an active researcher with a particular focus on malaria, a disease that was significantly affecting Rome and the Roman countryside (the "Campagna Romana") at the end of the 19th century.
The investigation of a wide variety of symptoms and morbid features led Baccelli to the discovery of the aphonic pectoriloquy, a phenomenon consisting in the modification of the voice heard on auscultation.
[3] In parallel to his career as a physician, Guido Baccelli was also an active politician who devoted significant time and effort to improving his home city, Rome, in numerous fields, ranging from agriculture to education.
[14] Baccelli's contribution to the cultural richness of Rome are not to be underestimated, most noteworthy are the opening of the galleria dell'arte moderna (Modern art gallery), the creation of the Archaeological stroll (Passeggiata archeologica) in the Imperial forum.
Quote: "Convince yourselves gentlemen that your first priority for your house in the capital is to make this evermore salubrious; add to this that one of the most degraded areas and closest to buildings is surrounded by the palatino on one side and the colosseum at the end of it and on its right the baths of Caracalla; and so from the grandiose of the ancient monuments becomes a proud sarcasm the present insalubrity.
[15][16] And the revival of ancient monuments which had been modified like the pantheon to this Pope Urbano 7th Barberini commissioned Bernini to add 2 bell towers which became popularly known as "The donkey's ears" these were removed by Baccelli in 1883 and some bronze letters were added to the facade in memory of Agrippa's work.
This would have granted more liberty to the proprietors of those woods to exploit them, Baccelli strongly opposed this law and to support his thesis he brought forward epidemiological data and in doing so provided a connection between deforestation and illness.