Commentary on Seersholm Et al.: Yersinia pestis Infection Is Not Synonymous With Deadly Plague in Neolithic Scandinavia

OBJECTIVES: Emerging genomic evidence has identified ancestral strains of Yersinia pestis in ancient human populations, which has sparked debates about its pathogenic role in later Neolithic societies. Here, we review published evidence linking anthropological and biological data reflecting the past natural history of Y. pestis infection. MATERIALS AND METHODS: Review of reported ancient Y. pestis genomes, paleomicrobiological, archaeological, and ecological data related to ancient plague. RESULTS AND DISCUSSION: While some researchers attributed the Scandinavian Neolithic population decline to plague epidemics, we argue that early Y. pestis strains were more likely associated with outbreaks of food-borne enteritis rather than flea-borne plague. This hypothesis is supported by genetic, archaeological, and ecological analyses, which indicate that Y. pestis evolved key flea-borne transmission mechanisms only later in its history.