Programmatic approaches to screening for active tuberculosis.

Passive case finding, the detection of tuberculosis (TB) cases among persons presenting to health facilities with symptoms suggestive of TB, has remained the principal public health approach for TB diagnosis. While this approach, in combination with improved treatment, has led to substantial global progress, the overall epidemiological impact has been inadequate. Stagnating case notifications and sluggish decline in incidence prompt the pursuit of a more active approach to TB case detection. Screening among contacts of TB patients and people living with human immunodeficiency virus infection, long recommended, needs scaling up. Screening in other risk groups may also be considered, depending on the epidemiological situation. The World Health Organization (WHO) has recently produced recommendations on systematic screening for active TB, which set out principles and provide guidance on the prioritisation of risk groups for screening and choice of screening and diagnostic algorithms. With a view to help translate WHO recommendations into practice, this concluding article of the State of the Art series discusses programmatic approaches. Published literature is scanty. However, considerable field experience exists to draw important lessons. Cautioning against a hasty pursuit of active case finding, the article stresses that programmatic implementation of TB screening requires a systematic approach. Important considerations should include setting clear goals and objectives based on a thorough assessment of the situation; considering the place of TB screening in the overall approach to enhancing TB detection; identifying and prioritising risk groups; choosing appropriate screening and diagnostic algorithms; and pursuing setting-specific implementation strategies with engagement of relevant partners, due attention to ethical considerations and built-in monitoring and evaluation.