Molecular isolation and identification of Mycobacterium avium subsp. hominissuis in Didelphis virginiana from Hidalgo, Mexico

Objective: To isolate and identify the exact species of the genus Mycobacterium from Didelphis (D.) virginiana, and the direct implications of this bacterium to public health and veterinary medicine. Methods: Thirty-one D. virginiana were captured and necropsied in Hidalgo, Mexico. Tissue samples were collected to culture mycobacteria present and examine individual specimens’ histopathology. Mycobacterium identification was obtained through the application of amplification and sequencing of 16S rDNA techniques. Results: Three strains were isolated and identified as Mycobacterium (M.) avium subsp. hominissuis by utilizing M. avium complex- specific primers. Granulomatous lesions were observed in the subpleural zone (granuloma grade Π ) and bronchial (granuloma grade I ) of the lungs of D. virginiana with positive isolation. Conclusions: Three strains of M. avium subsp. hominissuis, from lung tissue samples of D. virginiana were identified. This subspecies of M. avium has important implications in public health and veterinary medicine.