Screening

In order to obtain the required information for the indicators described above, a TB recording and reporting system needs to include a minimal set of data elements. Although paper-based systems have been used to collect such data, it is now becoming increasingly feasible to collect data electronically, and this should be the standard aspired to for monitoring TB screening activities. The following strategies can be used to collect the necessary data:

Continued monitoring can help programme managers assess the performance of the TB screening components that are within their purview. The following indicators should be considered for each targeted risk group:

1. the number of people eligible for screening;

2. the number of people screened (considering the first screening and second screening separately, if applicable);

3. the proportion of those eligible for screening who were screened;

4. the number of people with presumptive TB who were identified;

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) (1).

In this section, we consider the monitoring and evaluation required to support the implementation of TB screening programmes. The operational handbook contains more details about the monitoring, surveillance and evaluation of TB screening interventions (7).

Screening tests should distinguish between people with a high likelihood of having TB disease from those who are unlikely to have TB. A screening test is not intended to be diagnostic but rather to identify the subgroup of people with the highest likelihood of disease. Screening must always be conducted with a screening and diagnostic algorithm; thus, if people screen positive, they are referred to the next step in the algorithm, which could be a subsequent screening tool or diagnostic evaluation with bacteriological testing to confirm or rule out TB disease.

Tuberculosis (TB) is a major yet preventable airborne infectious disease. About one fourth of the world’s population is infected with TB bacilli, the vast majority of whom have no disease (1, 2). In 2019, an estimated 10 million new TB cases emerged worldwide, and more than 1.4 million people died of TB, making it the leading single infectious disease cause of death that year (2). Of the estimated 10 million people who fell ill with TB in 2019, TB was not diagnosed in an estimated 2.9 million, and they were not enrolled in quality-assured TB treatment (2).

mWRDs are now also recommended for screening people living with HIV. (See 3.1.4 for a full description of their use in screening). A positive mWRD screen result in a person with HIV must be followed by further diagnostic evaluation to confirm or rule out TB.