[Petechial typhus in Napoleonic Italy. Scientific debate and the role of Giovanni Rasori].

During the Napoleonic wars, an epidemic recrudescence of petechial typhus was observed throughout Europe. In Italy, the epidemic first broke out in Genoa, in 1799, coming from southern France, during the sieges of the Austro-Hungarian army. Giovanni Rasori, a young Republican physician and man of the sciences, supported the besieged and contributed to defend the city. From the beginning, Rasori identified the cause of the epidemic in petechial typhus, being able to evaluate its clinical presentation, and developed a pathogenetic theory, known as contrastimulus. At that time, this theory obtained some success, though opposed by the academic establishment in Lombardy. In this article, we present the medical and philosophical ideas which, in the period between the 18th and 19th century, pervaded medical Italian culture. Furthermore, a biographic profile of Giovanni Rasori is described, a courageous scientist who did not disdain to take part in political and cultural Italian life during a historical period that was to become important for the future fortunes of Italy.