On-host Flea Phenology and Flea-Borne Pathogen Surveillance among Mammalian Wildlife of the Pineywoods of East Texas

Flea-borne diseases are endemic in Texas, U.S.A., with an increasing incidence of flea-borne typhus and cat scratch disease. Knowledge of flea natural history could provide information to protect public health, yet many knowledge gaps remain outside of plague-endemic regions. Our objective was to characterize seasonal activity patterns of fleas on common mammalian wildlife species and test fleas and wildlife for Rickettsia and Bartonella pathogens. We performed one year of monthly trapping for rodents and medium-sized mammals in a national forest with high recreational use and urban encroachment in East Texas. From 90 mammal captures representing seven species, 101 fleas were collected representing Polygenis spp., Ctenocephalides felis, and Orchopeas species. Virginia opossums (Didelphis virginianus) hosted 99% of the collected fleas (100 fleas) and a single flea was on an eastern woodrat (Neotoma floridana). Flea infestation prevalence of opossums was 79% (23/29). Mean flea abundance was 4.39 fleas, with intensity peaking in spring. One cat flea removed from an opossum was positive for Bartonella henselae. Furthermore, we identified tissue or blood of four raccoons (Procyon lotor) and one golden mouse (Ochrotomys nuttalli) positive for Rickettsia amblyommatis. These findings provide an ecological basis for the maintenance of vectors and pathogens from sylvatic settings.