Giovanni Cosimo Bonomo (30 November 1666 – 13 January 1696) was an Italian physician, known for discovering the itch mite as the cause of the skin disease scabies.
[1] In 1684, Bonomo returned to Livorno where, upon the advice of his father, he began to attend the pharmacy of the famous naturalist and intimate collaborator of Redi, Giacinto Cestoni.
Before his father died in the first half of 1684, he recommended Bonomo, who was in poor economic conditions, to Redi, who helped him to get a job as a ship doctor.
Coupled with Cestoni's technical skill in using a microscope, he determined the cause of scabies, which was nothing more than itch mites gnawing in the skin of those afflicted.
Bonomo and Cestoni discovered and described "a very minute living creature, in shape resembling a tortoise, of whitish colour, a little dark upon the back, with some thin and long hairs, of nimble motion, with six feet, a sharp head, with two little horns at the end of the snout.
Upon his pleading, Redi published Bonomo's letter on 18 July 1687 as Osservazioni intorno a' pellicelli del corpo umano in Florence.
On 23 August 1687, Lancisi responded, referring to the discussion among academics and their essentially negative reactions both to his observations of the mite and his definition of scabies as its effect.
[1] Based on his theory of scabies, Bonomo developed a therapy of ointments, douches and baths, in which salts, mercury, sulfur, vitriols and other aggressive and penetrating substances were used.
He first accompanied Anna Maria Luisa de' Medici in 1692 to Neuburg an der Donau, Palatinate-Neuburg, and Düsseldorf, the capital of the Duchy of Jülich-Berg, where he was to monitor her pregnancy, which ended in miscarriage.
[1] After Bonomo's death, his pamphlet was discovered by the English physician Richard Mead, who was passing through Italy and included it as an abstract in the Philosophical Transactions of the Royal Society of London (XXIII [1702–03], No.