If the doctor did have fatal familial insomnia the idea has been suggested by his descendants in their search for the origin of their mutation he likely would have noticed his first symptoms there in the summer of 1764.

NPR: Book Traces Family Suffering from Deadly Insomnia

Many of the doctor's descendants would experience similar symptoms in the course of dying from fatal familial insomnia, suggesting that the Venetian doctor may have been the earliest recorded case of a disease that has gone on to torment his relatives for more than two centuries.

NPR: Book Traces Family Suffering from Deadly Insomnia