Chile's ancient mummies confirm smallpox introduced by European colonists

Scientists analyzing bone fragments from two 16th‑century mummies discovered at the Camarones archaeological site in northern Chile identified DNA of the smallpox (Variola) virus. The remains, dated between 1492 and 1631, contained viral genomes that sit between medieval European strains and later variants, providing the strongest genetic link yet that smallpox arrived in the Americas through European colonisation.

The study examined 13 bone samples, but only two showed clear evidence of infection. Researchers led by geneticist Shigeki Nakagome of Trinity College Dublin compared the ancient viral DNA with other historic genomes and concluded the virus likely entered the continent with early Spanish settlers, though the exact pathway—direct settlers or via the trans‑Atlantic slave trade—remains uncertain. Biologist Patricia Foster of Indiana University noted the finding confirms long‑standing historical accounts of European‑borne epidemics.

The discovery not only settles a centuries‑old debate about the origin of the disease in the New World but also raises new questions about how quickly the virus spread through indigenous trade networks before written records documented it.