Tuberculosis (TB) is a leading cause of death from a single infectious agent, despite being largely curable and preventable.
In 2019 an estimated 2.9 million of the 10 million people who fell ill with TB were not diagnosed or reported to the World Health Organization (WHO).
Systematic screening for TB disease can be done for an entire population (community-wide screening) or it can be targeted at selected risk groups or subpopulations of people who may be at higher risk of being exposed to TB, developing TB disease or suffering poor outcomes from the disease, or some combination of these. It can target people who seek health care (with or without symptoms or signs compatible with TB) and people who do not seek care (because they do not perceive that they have a health problem that warrants medical attention, barriers make it difficult to access health care, or for other reasons). Furthermore, screening can help identify people who are at particularly high risk of developing TB disease and thus may require repeat screening, for example, people with an abnormal CXR compatible with TB but who are not diagnosed with TB disease at the time of screening or people for whom TPT is recommended. Combining screening for TB with screening for TB risk factors can also help map individual- or community-level risk factors, comorbidities and socioeconomic determinants that need to be addressed to more effectively prevent the disease.
Strong recommendations are made for those risk groups or subpopulations for which the desirable effects of adhering to the recommendation are judged to clearly outweigh the undesirable effects: for these recommendations, screening is judged to be feasible, acceptable and affordable in all settings.
Conditional recommendations are made for those risk groups for which the desirable effects of TB screening probably outweigh the undesirable effects, but the trade-offs, cost–effectiveness, feasibility or affordability, or a combination of these, are uncertain. Reasons for uncertainty may include a lack of high-quality evidence to support the recommendation; limited evidence of benefit from implementing the recommendation; high costs or low feasibility or acceptability, or a combination of these.
Updated Guidance on Systematic Screening for TB
Key changes in the updated guidance
Link to the World TB Day 2021 site (contains links to the new guidance documents):
Link to a related WHO news release: