Revisiting the Medieval Black Death of 1347-1351: Spatiotemporal Dynamics Suggestive of an Alternate Causation

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Geography Compass




Recent research points to multiple inconsistencies regarding modern Yersinia pestis (in Bubonic, Pneumonic, or Septicemic Plague variants) as a causative agent for the Medieval Black Death (MBD). Published arguments at odds with a Y. pestis-caused epidemic include differences in recorded periodicity, seasonal mortality peaks, relevant biogeographical details, genetic findings, and spatiotemporal dynamics, among other inconsistencies. Here, we describe and expand on some of the recent literature noting these items. In addition, we discuss preliminary research related to our recently published theory, in which we agree with research suggesting that the MBD was caused by a virus, not a bacterium, and elucidate our contention that seasonal changes and medieval human trade patterns controlled the timing of peak mortality during the MBD and subsequent ‘plagues’. Epidemic evidence from the first epidemic wave and later outbreaks is presented in support of our hypothesis.