Mycobacterium bovis as an occupational hazard in abattoir workers.

Five cases of bovine tuberculosis occurred in a two year period in South Australia, which represents a higher incidence than in previous years. All five patients had a history of employment in an abattoir (although four different abattoirs were involved) and four of the cases had pulmonary or pleural TB. A voluntary survey of one of the abattoirs was conducted which discovered the fifth case of active pulmonary TB. We suggest that bovine TB should be considered an occupational hazard in abattoir workers, and that suitable pre-employment screening programmes for workers be established. The transmission of disease in these cases is almost certainly by inhalation causing pulmonary TB and is therefore different from the 'classic' form of bovine TB transmitted by ingestion of infected milk and resulting in extrapulmonary disease.