A Likely Plague Epizootic Involving Wild Lagomorphs in the Mojave Desert of California: Public Health and Ecological Implications

Abstract

Plague is a disease that poses serious threats to public and ecosystem health. Its causative bacterium, Yersinia pestis, was transported to North America around 1900, where it quickly became established in native rodent populations and spread throughout the western half of the United States by the mid-1900s. Many questions remain about plague circulation in the numerous rodent species involved, but its ecology in rabbits and other lagomorphs is even less understood. We describe a plague epizootic that appeared to involve both desert cottontail rabbits (Sylvilagus audubonii) and black-tailed jackrabbits (Lepus californicus). We believe this to be the first such description to involve both species of rabbits and the first description of a plague epizootic in the Mojave Desert. This epizootic also involved a human case of plague; we discuss human health ramifications of plague in rabbits and suggest a potential link between plague and the general long-term decline in rabbit populations, especially for jackrabbits.