That's very interesting for sure, Italy is not "prone" to having vampires, such as the likes of Eastern Europe. However, mass disease, like a plaque, were often thought to be brought on by "vampires."
However, what was described is not unusual. Many corpses were checked during the 15th and 16th centuries to make sure that a person wasn't a "vampire," especially if there were any indication that they were. If it were believed that person was a "vampire," then its body was mutilated for certain.
Common beliefs at how a person could become a "vampire" would include: suicide, drowning, or sudden death. (Some cultures believed that if an animal walked over the corpse they would become a "vampire.") If a person were born with teeth, or had a "tail" or was born with a "caul"-they were certain to be a "vampire."
Preventative measures were taken when a person was buried, just in case. It was commonly believed that the soul escaped via the mouth, so often times the mouths of the dead were tied shut or stuffed with items such as garlic, dirt, or wool, for instance...or maybe even a brick!