(AZ Republic) -- When a number of fleas infected with the plague was found in northern Flagstaff, it warranted some concern.
The disease is the same one that wiped out an estimated 60percent of Europe's population in the last millennium and barely left enough people alive to bury the dead. But scientists and public-health officials say modern amenities and advances have left the bug that carries the plague a minor threat to most Americans.
The bacterium, Yersinia pestis, persisted for centuries, causing three major outbreaks: the Justinian plague, the Great Plague and the Modern Plague. The last one began in China in the 1860s and spread to port cities around the world, including in the United States. It's still present in today's rodent populations.