DNA recovered from centuries-old mummies in Chile has provided the strongest evidence yet that smallpox arrived in the Americas after European colonization.
The recent research, published in the journal Science, centers on Chilean mummies whose ancient DNA yielded evidence of smallpox infections dating to the early colonial period.
Geneticist Shigeki Nakagome of Trinity College Dublin and his colleagues analyzed 13 bone samples previously collected from an archaeological site at Camarones in northern Chile.
EXPERTS IDENTIFY VICTIMS FROM ONE OF HISTORY'S MOST 'CATASTROPHIC' ARCTIC DISASTERS
They then uncovered evidence of two smallpox infections in one man and one woman believed to have died between 1492 and 1631.
While historians have long known that smallpox reached the Americas following European contact, the discovery marks the first evidence of the disease in that part of South America.
The research raises questions about how the virus traveled so far south.
Smallpox, which was eradicated in 1980 and no longer naturally circulates, was once one of the world's deadliest diseases.
EXPERTS FINALLY SOLVE MYSTERY OF TEENAGE REVOLUTIONARY WAR SOLDIER 246 YEARS AFTER HIS DEATH
It killed roughly one-third of those infected.
Those who survived the disease were often left disfigured and scarred.
Smallpox devastated Native populations after Europeans arrived in the Americas — and researchers are still unsure exactly who first brought the virus or how it spread across the continents.
CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER
The virus may have spread through long-established Native trade networks, while researchers say it also could have passed through Africa amid the expansion of the slave trade.
Patricia Foster, a biologist at Indiana University who was not involved in the research, told The Associated Press (AP) that the findings provide genetic proof of something historians have long understood.
CLICK HERE FOR MORE LIFESTYLE NEWS
"Nobody would ever question that smallpox came to this hemisphere from colonization, but this proves it," said Foster.
The discovery is the latest example of DNA offering new clues about diseases and deaths that have puzzled researchers for centuries.
TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZ
Earlier this year, researchers recovered ancient DNA from 5,500-year-old human remains in Colombia containing bacteria related to syphilis, pushing the known history of the disease back more than 3,000 years.
This summer, researchers analyzed ancient DNA from the remains of Renaissance ruler Francesco I de' Medici, potentially solving the centuries-old mystery surrounding his sudden death in 1587.
The Associated Press contributed reporting.