Summer sale: Save 58%

Leslie S. Leighton

A quarantine warning is displayed outside the horse racing track at Turf Paradise, Friday, Jan. 29, 2016, in Phoenix. Turf Paradise has euthanized one horse and is quarantining two others in the wake of a herpes outbreak that surfaced in New Mexico.(AP Photo/Matt York) (AP)

Quarantines have tried to keep out disease for thousands of years

Leslie S. Leighton