Jewish sanitary laws came from God

When the Black Plague hit Europe in the 14^th century it killed over 25 million people.  It was later determined that it was spread through fleas from infected rats.  Rats were in close proximity to people because of unsanitary practices (e.g. raw sewage in the streets).  Jewish populations weren’t as affected by the disease.  This brought suspicion and even persecution from panicked mobs.  The Old Testament laws commanded strict procedures for quarantining the sick and burial of human waste.  They also didn’t use public water sources (which had become infected) because of laws against defilement.  These practices protected them from much of the epidemic.  How did they know to do this?  It was in the Bible centuries before man “discovered” it.