Herodotus  tells us that the Jewish laws relating to leprosy were derived from the practice of the Egyptians. The same diseases indeed required the same remedies. These laws were unknown to the Greeks and to the early Romans, as was the disease. The climate of Egypt and Palestine made them necessary ; and the ease with which this disease spreads ought to make us see very clearly the wisdom and foresight of those laws.
We ourselves have experienced their effects. The Crusades had brought us leprosy ; the wise statutes that were enacted prevented it from spreading to the mass of the people.
We see from the law of the Lombards that this disease was widespread in Italy before the Crusades, and merited the attention of legislators.  Rotharis decreed that a leper cast out of his house and relegated to a particular place could not dispose of his property, because the moment he had been removed from his house he was considered dead ; to prevent any communication with lepers, they were made incapable of having possessions.
I think this disease was brought to Italy by the conquests of the Greek emperors, in whose armies there could be militias from Palestine or Egypt. However that may be, its advance was halted until the time of the Crusades.
It is said that Pompey’s soldiers brought back from Syria a disease much like leprosy. No statute enacted at the time has come down to us, but it is likely there were some, since the disease was suspended until the time of the Lombards.
Two centuries ago, a disease unknown to our fathers came from the New World to ours and attacked the human race in the very source of life and pleasures. Most of the greatest families of southern Europe perished from a disease that became too common to be dishonorable, and was now merely deadly. It was the thirst for gold that perpetuated this malady : men were constantly going to America, and forever bringing back new strains of it.
As it is incumbent on the wisdom of legislators to keep watch over the health of citizens, it would have been most sensible to halt this communication with laws written on the model of the Mosaic laws.
The ravages of the plague are even more immediate and rapid. Its principal seat is in Egypt, whence it spreads throughout the world. In most of the European states very good statutes have been enacted to prevent its establishment, and recently an admirable means has been conceived for checking it : a line of troops is placed around the infected country, which prevents all communication.
The Turks,  who have no policy on this subject, see the Christians in the same city escaping the danger, and themselves alone perishing : they buy the lepers’ clothing, put it on, and go their way. The doctrine of a rigid destiny that determines everything makes the magistrate into a tranquil spectator : he thinks that God has already done everything, and there is nothing for him to do.