ReacciónNote: The definitions listed below apply to the terms as used in these guidelines. They may have different meanings in other contexts.
Active case finding (ACF): is synonymous with systematic screening for tuberculosis (TB) disease, although usually implemented outside a health facility.
Adolescent: is a person aged 10–19 years.
Adult: is a person aged > 19 years.
Bacteriologically confirmed TB: refers to TB diagnosed in a biological specimen by smear microscopy, culture or a WHO-approved rapid diagnostic test such as Xpert® MTB/RIF or a urinary lipoarabinomannan assay.
Child: is a person aged < 10 years.
Contact: is any person who has been exposed to a person with TB disease.
Contact investigation: refers to the systematic identification of previously undiagnosed TB disease and TB infection (TBI) among the contacts of an index person and/or in settings where transmission occurs. Includes clinical evaluation and/or testing and provision of appropriate anti-TB therapy (for people with confirmed TB) or TB preventive treatment (TPT) (for those without TB disease).
High TB transmission setting: refers to a setting with a high frequency of individuals with undetected or undiagnosed TB disease, or where infectious TB patients are present and there is a high risk of TB transmission. TB patients are most infectious when they are untreated or inadequately treated. Transmission will be increased by aerosol-generating procedures and by the presence of highly susceptible individuals.
Household contact: is a person who shared the same enclosed living space as the index person for one or more nights or for frequent or extended daytime periods during the 3 months before the start of current treatment.
Index person with TB: is the initially identified person of any age with new or recurrent TB in a specific household or other comparable setting in which others may have been exposed. An index person is the one on whom a contact investigation is centred but is not necessarily the source.
Infant: is a child aged < 1 year (12 months).
People who use drugs: are those who engage in harmful or hazardous use of psychoactive substances, which could negatively affect their health, social life, resources and legal situation.
Programmatic management of TB preventive treatment (PMTPT): refers to all coordinated activities by public and private health caregivers and the community for providing TPT to people who need it.
Skin test: refers to the intradermal inoculation of either tuberculin (TST) or M. tuberculosis antigen (TBST) to elicit a response indicative of TBI.
TB preventive treatment (TPT): is treatment offered to individuals who are considered to be harbouring TBI and to be at risk of developing TB disease in order to reduce that risk. Also referred to as treatment of LTBI or TB infection, or TB preventive therapy.
Tuberculosis (TB): is the disease state due to M. tuberculosis. In this document, it is referred to as “TB disease” in order to distinguish it from “TB infection”.
Tuberculosis infection (TBI): is a state of persistent immune response to stimulation by M. tuberculosis antigens with no clinically manifest TB disease. Most infected people have no signs or symptoms of TB but are at risk of TB disease. TBI was previously referred to as “latent TB infection” or LTBI, but, as infection cannot always be considered latent, the term TBI (TBI) is preferred. There is no gold standard test for direct identification of M. tuberculosis infection in humans.
Underweight: in people ≥ 19 years, usually refers to a body mass index < 18.5 kg/m2 ; in people aged < 19 years, refers to a weight-for-age < –2 z-scores.