Health workers are exposed to numerous infectious diseases from which the patients they attend are suffering and that have been recognised as occupational infectious diseases. Those most frequently reported are acquired by the haematogenous path, especially hepatitis due to virus B. Numerous infectious diseases are transmitted through airways and until the coming of acute severe respiratory syndrome caused by a coronavirus, tuberculosis was one of the most dreaded. In this paper we analyse the reasons why tuberculosis is considered to be an occupational disease in health personnel; which activities entail most risk and the measures that should be adopted to reduce nosocomial transmission.