Ancient Chilean Mummies Provide First Genetic Proof Smallpox Arrived via European Colonization

Key points

• Geneticist Shigeki Nakagome and colleagues analyzed 13 bone samples from the Camarones site in northern Chile, recovering smallpox DNA from two individuals who died between 1492 and 1631.
• The recovered viral genomes are closely related to European strains, providing the first direct molecular link between European colonization and the introduction of smallpox to South America.
• The discovery was accidental; researchers were initially seeking human DNA for ancestry studies or tuberculosis markers but found well-preserved smallpox DNA instead.
• The study suggests the virus may have spread through Indigenous trade networks, as no historical records document a smallpox epidemic in northern Chile during that period.
• Smallpox, eradicated in 1980, killed approximately one-third of those infected and caused severe scarring in survivors, devastating Indigenous populations across the Americas.

Background

This development follows earlier reports in July 2026 that highlighted the significance of ancient DNA recovered from Chilean remains. Previous coverage noted that the CAM9 lineage sits between medieval European strains and later variants, offering clues on viral evolution. The current synthesis confirms these earlier findings, emphasizing that while the arrival of smallpox was historically accepted, this study provides the first tangible biological evidence linking the disease to European contact in South America.

How outlets are covering it

Fox News emphasizes the discovery as the 'strongest evidence yet' that smallpox arrived after colonization, quoting biologist Patricia Foster to highlight the definitive nature of the genetic proof. The Economic Times focuses on the accidental nature of the discovery, noting that researchers were looking for tuberculosis or ancestry data but found smallpox DNA instead, and details the victims' ages and burial practices. VICE highlights the viral evolution, suggesting the virus became a 'highly efficient killing machine' before reaching Indigenous populations with no immunity. All sources agree on the core finding but differ in emphasis: Fox News frames it as a historical confirmation, The Economic Times details the methodological surprise, and VICE focuses on the biological implications of the virus's lethality.

Why it matters

This finding resolves a long-standing historical question by providing direct biological evidence that European colonizers introduced smallpox to the Americas. It underscores the devastating impact of colonial contact on Indigenous populations, who lacked immunity to the disease. The discovery also offers insights into viral evolution, showing how smallpox adapted over centuries, and highlights the potential of ancient DNA to uncover historical truths that written records may have missed or omitted.

What to watch

Researchers will continue to analyze the smallpox family tree to understand how the virus evolved and spread across the Americas. Further studies may explore whether the virus spread through Indigenous trade networks or via the slave trade, as suggested by some experts. Additionally, the discovery may lead to new insights into other diseases that affected Indigenous populations during the colonial period, potentially revealing more about the biological history of the Americas.