Demographic and Genetic Impact of the 1742–1743 Plague Epidemic in Córdoba, Argentina: A Bioanthropological Perspective

Background: This study investigates the demographic, genetic, and socioeconomic impact of the 1742–1743 plague epidemic on Córdoba, a key region within the Viceroyalty of Peru. The research focuses on the epidemic’s influence along the Royal Road (Camino Real), the main route connecting Buenos Aires and Lima, addressing a historically overlooked period with a multidimensional approach. Methods: Historical records of deaths, baptisms, and marriages from the Córdoba Archbishopric Archive were analyzed using techniques from historical demography and bioanthropology. Variables such as endogamy, exogamy, average marital distance (AMD), and consanguinity coefficients were evaluated. Results: The findings reveal a significant increase in endogamy (75–82%) and a peak exogamy index of 375 during the 1740–1744 cohort. The AMD rose to 705 km during the epidemic, indicating a shift toward marriages involving individuals from more distant regions. The total consanguinity coefficient (Ft) reached 0.00056, with the non-random component (Fn) driving this increase, suggesting heightened genetic isolation. Conclusions: The 1742–1743 plague epidemic intensified genetic isolation and consanguinity, potentially increasing homozygosity and the prevalence of recessive conditions. These changes highlight the epidemic’s long-term impact on Córdoba’s genetic diversity and demographic patterns within the colonial context.