Leprosy has been the scourge of humanity since antiquity. In 1874, the Norwegian microbiologist Gerhard Armauer Hansen isolated Mycobacterium leprae, showing that it was a transmissible infection and not an inherited one, as it was believed for centuries. It should be noted that in the first century AD, Aretaeus of Cappadocia, a Greek-born physician who studied medicine in Alexandria and practiced in Rome, provided not only the earliest and best description of leprosy (leonine appearance, lepromas) but also assumed that transmission occurs primarily through the respiratory root.1,2 In his book, he distinguishes the notions of contagion and infection and states that “One can be infected by the breath of an infected person and transmit leprosy in his turn to others.”2