[1] His work De tumoribus praeter naturam (1553) contains what is probably the first description of scarlet fever: he reported on a disease of children different from measles that caused a red rash all over the body, however he didn't mention the common symptom of a sore throat.

In this capacity, he emphasized the continuing education of physicians and insisted that medicine be treated as a scientific discipline that collected objective knowledge to ensure optimal treatments.

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.

[5] 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.