Diagnostic testing of sera for microbial agents possibly related to FTLS Sera were tested by reverse transcription (RT)-PCR, PCR, and/ or indirect IFA serological assays for a number of microbial agents, including A. phagocytophilum, Ehrlichia chaffeensis, Dengue fever virus, Japanese encephalitis virus, Chikungunya virus, Eastern equine encephalitis virus, Western equine encephalitis virus, Crimean-Congo hemorrhagic fever virus, Rift Valley fever virus, Sandfly fever Naples Sabin virus, and Hantavirus [3] [4] [5] [6] [9] [10] [11] [12] [13] [14] [15] [16] 23] . Antigen slides for diagnosis of HGA (A. phagocytophilum) were purchased from Focus Diagnostics (IF1450G, CA, USA). Antigen slides for diagnosis of other pathogens were prepared by our laboratories. Fluorescein isothiocyanate (FITC)-conjugated goat anti-human