Subclinical BCG-osis in a Captive Badger (Meles meles) with Lymphoma

Subclinical systemic dissemination of Bacillus Calmette-Guérin (BCG) is described in a captive badger (Meles meles) with lymphoma. An adult female European badger was vaccinated per os with BCG and after 8 weeks post-mortem examination identified marked lymphadenomegaly and multinodular hepatic lesions. The histopathology and immunohistochemistry confirmed a multicentric T-cell lymphoma, associated with high BCG bacterial load in numerous tissues. The histology did not identify BCG-associated lesions. The scenario suggested that the T-cell lymphoma likely favoured the dissemination of the BCG ('BCG-osis'). Given that lymphoma is rare in badgers, this neoplasm should not interfere with the efficacy of large-scale vaccination programmes.