Operational definitions

Clinical description

Systematic screening for active TB This is the systematic identification of people with presumptive TB in a pre-determined target group, using tests, examinations or other procedures that can be applied rapidly. Among those screened positive, the diagnosis needs to be established by one or several diagnostic tests and additional clinical assessments, which together have high accuracy.

2 WHO. Systematic screening for active tuberculosis.2015. http://apps.who.int/iris/bitstream/10665/181164/1/9789241549172_eng.pdf?ua=1. Ac- cessed 27 March 2017.

18 National Tuberculosis Control Programme Active TB case-finding This is health care provider-initiated screening process that is implemented at community level in pre-determined geographical area using standard tests.

Intensified case finding (ICF)

This is a health care provider-initiated TB screening among PLHIV.

Enhanced TB case finding (ECF)

The creation of population awareness of TB symptoms through advocacy and community mobilization to encourage self-presentation for TB screening.

Passive tuberculosis case-finding A patient-initiated pathway to TB diagnosis involving:

• a person with active TB experiencing symptoms that he or she recognizes as serious;
• the person having access to and seeking care, and presenting spontaneously at an

appropriate health facility;

• a health worker correctly assessing that the person fulfils the criteria for presumptive

TB; and

• The successful use of a diagnostic algorithm with sufficient sensitivity and specificity

to diagnose TB.

Contact investigation Contact investigation is a systematic process intended to identify previously undiagnosed cases of TB among the contacts of an index case. In some settings, this includes testing for LTBI to identify possible candidates for preventive treatment. Contact investigation consists of two components, Identification and prioritization and clinical evaluation.3 Index Case For contact investigation, the index case is the initially identified and diagnosed case of new or recurrent pulmonary TB (bacteriological confirmed TB, including MDR /XDR TB and new clinically diagnosed Pulmonary TB) in a setting where others may have been exposed.

Household Contact A person who shared the same enclosed living space for one or more nights or for frequent or extended periods during the day with the index case during the 3 months before commencement of the current treatment episode.

Close TB Contact A person who is not in the household but shares an enclosed space (such as a social gathering, workplace, or facility) for extended periods with the index case (definition below) during the three months before the commencement of the current treatment episode 2 3 WHO. Recommendations for investigating contacts of persons with infectious tuberculosis in low- and middle-income countries. 2012.

http://apps.who.int/iris/bitstream/10665/77741/1/9789241504492_eng.pdf?ua=1. Accessed 30 March 2017.

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