By about 450 BC, malaria had arrived in Rome. By the second century BC, malaria was endemic. It affected the lives of Roman people. To prevent infection, the popes adopted the custom of ancient affluent Romans who used to spend summer months in high plains far from Rome. The first to adopt the custom was Paul I in 767, who just moved his residence to Saint Paul, out of the walls. Sixtus V started the Congregation of Waters and Streets, which was routinely reinforced by his successors until 1860, when the Kingdom of Italy was born.