Leviticus 13 (résumé): Regulations about Infectious Skin Diseases

At the time that Leviticus was written the matter of skin diseases was clearly a great concern as can be seen by the dedication of two long chapters to them. I am sure dermatologists must be delighted. It is also interesting to note that it is the priests who coordinate the skin disease control. It was previously mistakenly thought that this chapter was a discussion of leprosy as can be seen in older translations such as that of Almeida Revista e Atualizada in Portuguese. However as G. J. Wenham points out this is incorrect, as the more modern translations reflect such as NIV. So in this chapter 21 different cases of skin diseases are distinguished as are 3 cases of "diseased" garments with mildew. 

So it was that if anyone had symptoms of skin problems they were to present themselves to the priest who was to examine them and if the hair in the sore had turned white, and the sore was more than skin deep, then the patient would be declared ceremonially unclean and he would be put in isolation. He would have to wear torn clothes, let his hair be unkempt, cover the lower part of his face, cry out unclean and live outside the camp.

However, if the diagnosis was dubious then the patient would be put in quarantine for two weeks and kept under observation every 7 days.

Thus the chapter proceeds to give instructions on how to examine a swollen sore, a boil, a burn, sores in the head, raw flesh, bright spots, skin conditions causing hair loss, itchy diseased skin etc. so as to determine whether the condition is more serious requiring the diagnosis of unclean or not. And when the skin condition cleared up the person could be re-examined by the priest and declared clean again and return to normal life.

Attached to the question of skin disease the latter part of the chapter discusses the problem of mildew which is a mold-like fungus. Quite why the link between skin disease and fungus I don't know, but the concern was about mildew on clothes and leather articles. This matter was also adjudicated by the priest and contaminated articles were defined as unclean and had to be burnt.