Human mortality and survival may have improved in the generations following the Black Death, according to results published May 7, 2014, in the open access journal PLOS ONE by Sharon DeWitte from University of South Carolina.
As one of the most devastating epidemics in human history, the medieval Black Death (c. 1347-1351) killed tens of millions of Europeans. Previous studies have shown that the disease targeted elderly adults and sick or stressed people; however, not much is known about any substantial changes in the population, like overall health and mortality, before and after its occurrence.
Following the epidemic, standards of living—particularly diet—improved, and in this study, Dr. DeWitte examined whether the deaths of frail people during the Black Death, combined with consequent rising standards of living, may have resulted in a healthier post-epidemic population in London. Unfortunately, most available data is in historical documentation (e.g., tax records and postmortem analysis), but in this study, Dr. DeWitte sampled nearly 600 skeletons from several pre- and post-Black Death London cemeteries and then analyzed their age and modeled age estimates, mortality hazards, and birth rate data for these samples.
Post-Black Death samples had a higher proportion of older adults, suggesting that survival may have improved following the epidemic. Additionally, results of hazards analysis indicate that overall, mortality risks were lower in the post-Black Death population than before the epidemic. Together, these results may indicate enhanced survival and decreased mortality after the Black Death, and by inference, improved health in some age groups in the post-epidemic population.
Although other factors could have influenced these differences, like the migration of people to London after the plague, Dr. DeWitte suggests that this study highlights the power that infectious diseases may have in shaping population-wide patterns of health and demography over both the short- and long-term.
Sharon DeWitte added, “This study suggests that even in the face of major threats to health, such as repeated plague outbreaks, several generations of people who lived after the Black Death were healthier in general than people who lived before the epidemic.”
Header Image : Illustration of the Black Death from the Toggenburg Bible (1411)
Contributing Source : PLOS