Identification of microbial pathogens in Neolithic Scandinavian humans

With the Neolithic transition, human lifestyle shifted from hunting and gathering to farming. This change altered subsistence patterns, cultural expression, and population structures as shown by the archaeological/zooarchaeological record, as well as by stable isotope and ancient DNA (aDNA) data. Here, we used metagenomic data to analyse if similar transitions in the microbiome composition could be found in 25 Mesolithic and Neolithic hunter-gatherers and 13 Neolithic farmers from several Scandinavian Stone Age cultural contexts. Two pathogenic species of the genus Neisseria were identified in individuals from both Mesolithic and Neolithic hunter-gatherers and represent the earliest findings of these species. Salmonella enterica, a bacterium that may have been the cause of death for the infected individuals, was only found in Neolithic samples from Battle Axe culture contexts. Several species of the bacterial genus Yersinia were found in Neolithic individuals from Funnel Beaker culture contexts as well as from later Neolithic context. Transmission of e.g. Y. enterocolitica may have been facilitated by the denser populations in agricultural contexts.