Plasmodium falciparum immunodetection in bone remains of members of the Renaissance Medici family (Florence, Italy, sixteenth century)

Medical accounts and ancient autopsy reports imply that tertian malarial fevers caused the death of four members of the Medici family of Florence: Eleonora of Toledo (1522-1562), Cardinal Giovanni (1543-1562), don Garzia (1547-1562) and Grand Duke Francesco I (1531-1587). All members of the Medici family hunted in the endemic malarial areas of Tuscany, such as the marshy areas surrounding their villas and along the swampy Maremma and were, therefore, highly exposed to the risk of being infected by Falciparum malaria. To determine if the original death certificates issued by the court physicians were correct, we carried out immunological investigations and then compared the biological results to the historical sources. Bone samples were examined for the presence of Plasmodium falciparum histidine-rich- protein-2 (PfHRP2) and P. falciparum lactate dehydrogenase (PfLDH) using two different qualitative double-antibody immunoassays. Our findings provide the first modern laboratory evidence of the presence of P. falciparum ancient proteins in the skeletal remains of four members of the Medici family. We confirm the clinical diagnosis of the court physicians, using modern methods. Finally, this study demonstrates that immunodetection can be successfully applied not only to mummified tissues but also to skeletal remains, thus opening new paths of investigation for large archaeological series.