Plague epizootic dynamics in chipmunk fleas, Sierra Nevada Mountains, California, USA, 2013–2015

Abstract

We describe Yersinia pestis minimum infection prevalence in fleas collected from Tamias spp. chipmunks in the Sierra Nevadas (California, USA) during 2013–2015. Y. pestis–positive fleas were detected only in 2015 (year of plague epizootic), mostly in T. speciosus chipmunks at high-elevation sites. Plague surveillance should include testing vectors for Y. pestis.