Wet springs and warm summers followed by dry cold snaps in Central Asia killed off flea-carrying great gerbils (Rhombomys opimus), possibly leading plague-harboring fleas to switch hosts and travel to Europe, according to a study published this week (February 23) in PNAS. The research provides evidence that repeated European plague outbreaks in the four centuries following the original Black Death (1347-1353) were due to reintroductions of the disease rather than a latent reservoir of the responsible Yersinia pestis bacterium in local rats.
Norwegian and Swiss researchers analyzed records of more than 7,700 European plague outbreaks between 1346 and 1837, finding 61 outbreaks in 17 harbors such as London, Hamburg, and Dubrovnik, which were likely imported with Asian shipments. In 16 separate years during that period, ...
