Identification of Aspergillus terreus and Aspergillus pseudonomiae as causative agents of aspergillosis in endangered Okinawa Rails

We identified and characterized <i>Aspergillus terreus</i> and <i>Aspergillus pseudonomiae</i> as causative agents of aspergillosis in two captive Okinawa Rails. In Case 1, an <i>A</i>. <i>terreus</i> isolate showed low susceptibility to voriconazole. It remains unclear whether this low susceptibility was intrinsic or acquired during antifungal treatment. Two phenotypically distinct isolates of <i>A</i>. <i>pseudonomiae</i> were obtained from the second case. One of them lacked sclerotia and aflatoxin production, suggesting a possible adaptation during infection. This is the first report of <i>A</i>. <i>pseudonomiae</i> isolation from animal hosts in Japan. Accurate identification and genomic analysis of <i>Aspergillus</i> isolates provide insights into antifungal resistance and the ecological dynamics of aspergillosis in Okinawa's forest environment, with important implications for wildlife conservation.