Background: Health care workers (HCWs) are occupationally exposed to a multitude of biological hazards, and among these to the risk of tuberculosis (TB) infection, especially involving individuals working in specific workplace (TB and Chest divisions, Infectious Diseases wards, Microbiology laboratories) and performing thoracic endoscopy and "cough-inducing" procedures. According to national legislation (title VIII D.lgs. 626/94, 1998 Health Minister guide lines document) concerning the control and prevention of TB transmission among HCWs, health care facilities are required to (i) perform an accurate risk assessment and (ii) implement an exposure control plan and worker health surveillance program, thus involving the occupational health professionals.
Objectives: The aim of this paper is to provide a general view of the epidemiological and scientific evidence related to the effectiveness of health interventions in the prevention of occupational TB infection.
Methods: Comparative evaluation and critical review of U.S. CDC (1994) guidelines, OSHA (1997) rules, and the most recent ATS and CDC (2000) "statement" documents.
Results: In low risk groups TCT shows decreased positive predictive value, high variability, and can be confounded by other factors (age, BCG, MNT), thus reducing its diagnostic value for latent TB infection.
Conclusions: Recent recommendations on the control of TB infection in health care settings underline the need of implementing accurate risk evaluation in all hospital units, compared to the epidemiological profile in the community, and "targeted tuberculin testing" programs among high risk HCWs.