It seemed no amount of praying could diminish the plague’s wrath. By the time city officials realized it was the rats that were causing the disease, … - Dan Brown

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It seemed no amount of praying could diminish the plague’s wrath. By the time city officials realized it was the rats that were causing the disease, it was too late, but Venice still enforced a decree by which all incoming vessels had to anchor offshore for a full forty days before they would be permitted to unload. To this day, the number forty — quaranta in Italian — served as a grim reminder of the origins of the word quarantine.