High-quality services for TB diagnosis, treatment and management and support services for patients should be in place before or scaled up at the same time as systematic screening for TB disease. The availability of high-quality TB services will minimize the risk of negative effects of screening, including the risk of a false-positive result and the accompanying anxiety, the risk of a false-negative diagnostic test and unnecessary treatment and delay in receiving an appropriate diagnosis (especially if the quality of TB diagnostic services is suboptimal) or worsening of TB treatment outcomes if treatment services are suboptimal and not properly tailored to the vulnerable groups that may be targeted through screening. Moreover, systematic screening in the context of poor-quality general services raises ethical concerns and may reduce the confidence of the population in the services provided. In addition, the capacity of specific health institutions and health staff to take on additional functions related to TB screening should be carefully assessed to avoid undermining the quality of TB and other services. Where people would benefit from systematic screening for TB but high-quality services and health system capacity for TB diagnosis, treatment, management and support are not in place, the gaps should be identified and should serve as an impetus for investment to improve TB services and capacity in those areas.
The critical conditions to be met or strengthened when implementing systematic screening are listed below.
- Quality-assured diagnostic services are available, including specimen transport from the community to the nearest health facility for onward transport or to the nearest laboratory. The services should include the capacity to deal with anticipated increased demand in diagnostic testing.
- Regular, reliable supplies of anti-TB medicines are available, and there is the capacity to treat the anticipated rise in cases of drug-susceptible as well as drug-resistant cases among adults and children.
- Regular, reliable supplies of TPT medicines are available, as those who are screened and do not have TB may be eligible for TPT.
- There should be sufficient integration between TB and HIV services to ensure that all people with possible TB are tested for HIV.
- The performance of TB diagnostic and treatment services must be considered acceptable by decision-makers, and processes should be in place to monitor and maintain quality
- There are sufficient mechanisms to provide social support for diagnosed patients, and there is capacity to tailor treatment programmes to the specific needs of the population to be screened.
- If mWRDs are used to assess drug resistance, there is adequate capacity for further drugsusceptibility testing and for programmatic management of drug-resistant TB.
- A mechanism should be in place to ensure that access to tests (mWRDs, radiography, other) for diagnostic purposes is appropriately prioritized in relation to tests for screening.
- Adequate financial and human resources can be made available for screening without adversely affecting other key functions of the health-care system.