Two skeletons from a burial site in northern Chile called Camarones 9 have been sitting in a museum collection for years, mummified naturally in the Atacama’s punishing aridity, catalogued as part of a Late Period Inca-affiliated community with signs of Spanish contact. Nobody was looking for a virus in them. The bone samples had been collected to study human DNA, not pathogens. But when researchers1 ran the femur fragments through a pathogen-screening pipeline, two of the thirteen individuals came back positive for variola virus, the cause of smallpox.
That’s the kind of find that sounds almost too clean, and for a while, epidemiological history has run on exactly this kind of narrative without the molecule to back it up. We’ve had the written record: Columbus arrives in 1492, a documented outbreak hits the Caribbean in 1518, the disease reaches Mexico by 1520, spreads down through the Isthmus of Panama into Inca territory by 1525, and eventually finds its way to Chile, with a well-documented 1561 outbreak generally marking its confirmed regional arrival. What we haven’t had, until this study, is the virus itself, isolated from a body that lived through it, with a genome that can be dated, sequenced, and placed on a family tree.
That’s what makes the Camarones 9 genomes matter. They’re not just old. They’re the first ancient smallpox genomes ever recovered from the Americas, full stop.
