Two cases of smallpox from 1540 CE circum-contact (early colonial) Northern Coastal Peru

Objective

This project seeks to create a differential diagnosis for lesions found on the skeletal remains of two children as a means to explore the presence of viral disease in 16th- century Peru.

Materials

Extremely well-preserved human remains of two children who died between the ages of 1–2 years old, recovered from the circum-contact (∼1540 CE) cemetery in Huanchaco, Peru.

Methods

Macroscopic and radiographic analysis.

Results

Both individuals present with cortical thickening, symmetrical destructive lesions, metaphyseal expansion, perforations, exposure of the medullary cavity, resorption of metaphyseal ends and necrosis of the long bones, and deposited reactive new bone. These features are consistent with osteomyelitis variolosa and bacterial osteomyelitis.

Conclusions

Three features of Individuals IG-124 and IG-493 suggest a highly consistent diagnosis of osteomyelitis variolosa: multiple skeletal lesions, the historical context of the area, and the high mortality rate of non-adults in the circum-contact cemetery.

Significance

Although viral infections are ubiquitous and well documented historically, their etiologies are often difficult to determine in archaeological populations. Orthopoxvirus variola (smallpox) is one of the many viruses whose archaeological impact is still under explored in skeletal remains.

Limitations

The absence of smallpox in other children from the Huanchaco cemetery creates difficulty in ascertaining true prevalence rates or information on potential outbreaks.

Suggestions for further research

Further research analyzing aDNA from calculus and/or residues using a DIP-GC-MS method might create a better understanding of how smallpox spread through the region.