A 45-year-old woman died of meningitis in Florence on Monday soon after she arrived at the Santa Maria Nuova hospital's emergency room.
Public health services are giving preventive treatment to around 20 people who were in close contact with the woman, a Florence native.
The woman died of sepsis from meningitis C and had not been vaccinated against the disease, an immunology lab confirmed.
Meningitis is highly contagious and can kill rapidly if left untreated.
There have been several meningitis cases in the Tuscany region surrounding Florence and the neighbouring Emilia Romagna region since last year, some of them fatal.
As recently as in August this year, a 19-year-old woman died in Vienna as she was returning to Italy from the Catholic Church's World Youth Day event in Krakow, Poland. The student came from Rome and had stayed in Tuscany the week before her death.
The maximum incubation period for the meningitis bacteria is 10 days.
Italy's health minister Beatrice Lorenzin has strongly urged the public to get vaccinated against the disease.