16th-Century Skeletons of Children Infected With Smallpox Discovered in Peru

Researchers in Peru have concluded that two toddlers buried in the 16th century were victims of smallpox—specifically, a rare bone infection caused by the smallpox virus. The children died during the Europeans’ early colonization of South America, and their story has shed new light on disease outbreaks in the region.

The children’s remains were found in a cemetery in Huanchaco, a city on Peru’s northern Pacific coast. Huanchaco made news in recent years when archaeologists found a mass grave of over 260 children—many with their hearts removed—thought to be victims of a mass sacrifice 500 years ago.

Recent excavations revealed another graveyard in the town, near a church built by Spanish colonists around 1535. This cemetery holds 120 burials belonging to both colonial Europeans and the Indigenous Chimu-Inka people, according to a study published this month in the International Journal of Paleopathology.

The graves provide new insights into colonial influence in the area. For instance, Indigenous individuals were buried with Christian crosses and European glass beads, suggesting attempts at religious conversion.

As historians well know, European colonists brought much more than beads and Christianity to South America. They also carried diseases previously unknown to local communities. One of those was smallpox, a highly contagious sickness that caused millions of deaths over thousands of years before its eradication.

“Smallpox and other novel infectious diseases affected the most vulnerable segments of the Andean north coast population,” write the researchers. Smallpox probably traveled from Europe to Peru with conquistador Francisco Pizarro in the 1530s. By 1620, infectious disease had wiped out over 70 percent of the Indigenous occupants of Peru’s northern coast.

Children suffered the most. Over 67 percent of the burials in the Huanchaco cemetery belong to infants and children under 12, whose developing immune systems would have made them especially vulnerable to disease.

Upon careful examination, researchers found the skeletons of two interred children—who died between the ages of 1 and 2—to be abnormal. There were “numerous destructive lesions, almost like moth holes, in the joints of the kids’ shoulders, elbows, wrists, hips, knees and ankles,” writes Live Science’s Kristina Killgrove. The lesions are marks of a bone infection, osteomyelitis variolosa, caused by the smallpox virus.

These cases of osteomyelitis variolosa are the earliest ever found in South America—“which is surprising given the numerous smallpox outbreaks that occurred after European contact,” writes Live Science.

As lead author Khrystyne Tschinkel, a bioarchaeologist at Hamline University, tells All That’s Interesting’s Amber Morgan, there is a lack of reliable data on disease spread and impact in some Indigenous South American populations. Still, the lesions provide some hints about these particular children’s experiences.

“We can guess that it is possible, after their symptoms started, that they lived with smallpox for a few weeks,” Tschinkel tells Live Science. “There was enough time for the bones to become severely infected.”

Not all smallpox patients experience bone deformities, but the researchers think many archaeological cases have yet to be identified. As they write in the study, disease alters populations for many years after an outbreak, and “understanding how viruses and humans have interacted across time can contribute to how current and future societies evaluate new and emerging diseases.”

As Tschinkel tells All That’s Interesting, identifying these particular cases of smallpox helps historians develop a more comprehensive understanding of early colonial outbreaks.

“What we can say is that there was likely a smallpox outbreak in Huanchaco around 1540, and if it was happening there it was likely it was also happening nearby,” she adds. “It is a small piece [of] the puzzle, and I hope to continue to add more pieces.”

Sonja Anderson | READ MORE

Sonja Anderson is a writer and reporter based in New York City.