The plague is not dead.

Scientists recently discovered a collection of 1,500-year-old teeth from two people who met their demise after having been inflicted with the Justinian plague. DNA results indicate this illness is what mutated years later and wiped out millions of people.

Researchers published their findings in the latest issue of the journal Lancet Infectious Diseases, which shows the correlation between the pathogen that caused the Justinian Plague of the 6th Century and the Black Death of the 14th Century that was responsible for killing over 50 million Europeans.

Scientists believe their findings prove that the plague is simply lying dormant and could quite possible come back to kill again.

“What this shows is that the plague jumped into humans on several different occasions and has gone on a rampage,” said Tom Gilbert, professor at the Natural History Museum of Denmark. “That shows the jump is not that difficult to make and wasn’t a wild fluke.”

However, his message is more speculation laced with fear than something for civilization to worry about. There are actually thousands of cases of the plague every year all over the world, including the United States.

The plague is most commonly spread through rodent fleas. And while it can still be fatal, there haven't been any major outbreaks in many years.