ReacciónIn 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).
When considering implementing screening in the general population, it is important to know the epidemiology of TB and the prevalence of undetected TB in the community. This will help to estimate the impact of any screening programme. TB disease prevalence surveys are used to assess the baseline occurrence of TB in high-burden settings (81). However, these surveys represent a major undertaking and are not practical in all situations. Surveillance data based on TB notifications can be used as a starting point, but it must be carefully considered alongside other factors that affect the risk of TB and the likelihood of diagnosis, including the availability of health services and the prevalence of other risk factors for TB (e.g. HIV, diabetes mellitus, smoking, malnutrition, poverty, overcrowded living conditions, older age, substance use disorder, and other lung conditions, including silicosis or fibrotic chest lesions).
In settings that are generally considered to have a higher TB burden than is found in the overall population, such as prisons, careful monitoring and surveillance to assess TB prevalence and incidence should be done alongside TB screening. If the burden of TB is found to be low and sustained at a low level for a period of time, then TB screening can be discontinued. However, surveillance should be conducted to minimize the risks of TB disease and transmission.