In ancient times, leprosy was a greatly feared disease. The Centers For Disease Control report that:

Hansen's disease (also known as leprosy) is a long-lasting infection caused by bacteria. The disease was once feared as a highly contagious and devastating disease. Now, however, the disease is very rare and easily treated. Early diagnosis and treatment usually prevent disability related to the disease.[i]

Did you know that Canada had leper colonies?

Sheldrake Island, New Brunswick was set up as a lazaretto in 1844. 18 people with leprosy (including children) were forced to live in isolation on the island. Social services dropped off food and firewood, but they were not allowed to leave. More were added to the colony. Five years later a new colony was established in Tracadie, New Brunswick and the Sheldrake lepers were moved. There were now 31 people and all Caucasian.

The Religious Hospitallers of Saint Joseph came from Montreal, in 1868 to take care of the lepers at Tracadie and they continued this ministry until the last leper left in 1965.[ii] 

There was another island colony in British Columbia. D’Arcy Islands were a destination with no return.

From 1891 till 1924 these islands were home to a lazaretto, or leper colony. People who were discovered to have leprosy were simply exiled there, with no possibility of reprieve. The lazaretto was first established by the municipal council of Victoria in 1891. They did it in response to five Chinese lepers being discovered in a shack in Chinatown. The traditional horror of this disease moved the council to action.[iii] 

All residents of D'Arcy Islands colony were Chinese. 

When we read about leprosy in the Scriptures, we are exposed to the same protective fear that we still have about modern diseases. Lepers in Israel had to live outside the community and were not allowed to associate freely. One with the disease was required to warn you verbally at a distance so you would stay away. They believed that it was contagious and so lepers were permanently quarantined.

If you were pronounced unclean, the only way to be restored to the community was to have the priests examine you. If they determined that you were not diseased, you could come back into society. The modern priests of medicine are whom we see now to get a clean bill of health.