"Plague's 'durability' over the ages as an infectious disease of major consequence for society stands in testimony to the ability of 'Yersinia pestis' to convert changes within its established, time-specific, host-agent-environment relations into opportunities that favor agent perpetuation through disease persistence and geographic expansion. Clearly, the ecology of plague is highly complex, a factor that contributes to various aspects of its ecology not yet being fully understood. The authors of this publication have admirably addressed this complexity within the context of an extraordinarily rich, well-illustrated, easily read and highly insightful synopsis for one of the classic and intriguing diseases of humanity. There is much to be contemplated here, taken into consideration, and acted upon, especially as the further urbanization of society continues to enhance opportunities for sylvatic plague. This situation involves both the movement of animals into 'metropolis' and the extension of 'metropolis' into free-ranging animal habitats."
National Wildlife Health Center, USGS Circular 1372
Geological Survey: http://pubs.usgs.gov/