Deer keds are blood-feeding flies from which several human and animal pathogens have been detected, including the causative agent of Lyme Disease (Borrelia burgdorferi). Cervids, which are the primary hosts of deer keds, are not natural reservoirs of B. burgdorferi, and it has been suggested that deer keds may acquire bacterial pathogens by co-feeding near ticks that are infected with the bacteria. We tested this hypothesis by using a molecular assay to screen for presence of Anaplasma spp., Bartonella spp., Borrelia spp., and Rickettsia spp. in specimens of European deer keds (n=306) and blacklegged ticks (n=315) collected from 38 individual white-tailed deer in Pennsylvania. There was limited similarity in the bacterial DNA detected between these ectoparasites per host, suggesting that co-feeding may not be a mechanism by which deer keds acquire these bacteria. We discuss these results in relation to deer ked feeding biology, life history, and collection timepoints. In addition, we screened specimens of European deer keds (n=410), Neotropical deer keds (n=13), Western American deer keds (n=10), and Pacific deer keds (n=14) for these same bacterial pathogens.