His 1560 work "Trattato assai bello et utile dei doi mostri nati in Palermo in differenti tempi" contains the detailed description of two cases of Siamese twins born in Palermo. To combat endemic malaria, he ordered the draining of surrounding swamps and instituted isolation hospitals for contagious patients. He managed the outbreak of the plague in Sicily in 1575/1576 by ordering measures of hygiene and separating suspected, confirmed and convalescing cases in different hospital wards. In his 1576 book "Informatione del pestifero, et contagioso morbo" he described the disease, traced its outbreak in Sicily, and was the first to recommend public health countermeasures. In 1578 he wrote "Methodus dandi relationes pro mutilatis torquendis aut a tortura exusandi", an evaluation, from an anatomical standpoint, of the contemporary methods of torture employed by the Roman Inquisition. The work was not published until 1914. He died in 1580 in Palermo and was buried there in the Church of San Domenico.  https://books.google.it/books/about/Giovan_Filippo_Ingrassia_e_le_costituzio.html?id=WxGCMAEACAAJ&redir_esc=y