Coccidioides immitis isolated from armadillos (Dasypus novemcinctus) in the state of Piaui, northeast Brazil

Natural infection of armadillos with Coccidioides immitis was studied in th e state of Piaui, northeast of Brazil, endemic for coccidioidomycosis. In 1 998, 26 nine-banded armadillos (Dasypus novemcinctus) were captured in 4 di fferent counties. The animals were sacrificed under deep anesthesia with et her. At necropsy fragments of spleen, liver, lungs and heart were homogeniz ed and seeded onto Sabouraud dextrose agar with and without cycloheximide ( BBL, USA). Part of each organ was also processed for histological examinati on. Suspected colonies of filamentous fungi observed after the second week of incubation at room temperature, exhibiting barrel-shaped arthroconidia a lternating with empty spaces, were inoculated intraperitoneally into mice. Three armadillos proved to be infected with C. immitis. Mice inoculated wit h suspected colonies obtained from homogenized spleen of three and liver of two armadillos developed disseminated coccidioidomycosis and immature and mature spherules of C. immitis were disclosed in several organs. For the fi rst time armadillos (D. novemcinctus) were found naturally infected with C. immitis, adding new data on the ecology and on a possible role of these an cestral mammals in the evolutionary life cycle of this fungus.