A new study published in the journal PLOS Medicine reveals that one of the reasons why many countries have not yet implemented the five interventions recommended by the World Health Organization could be because of a lack of evidence that they are effective in controlling tuberculosis.
Over the past few years, WHO has recommended that countries implement several interventions to help control the spread of tuberculosis through measures to improve prevention, diagnosis, and treatment. The authors led by Frank Cobelens from the Amsterdam Institute of Global Health and Development in the Netherlands reviewed 208 appropriate studies to investigate the evidence for the effectiveness of each of these interventions and also for additional information on the setting and conditions of implemented interventions, which might be useful to other countries.
The authors found that there were very few real-world studies reporting on the effectiveness of interventions in program settings (rather than in optimal conditions under research settings). Few studies evaluated the methods used to implement the intervention or addressed delivery and operational issues (such as adherence to treatment) and there were few economic evaluations of the recommended interventions.
The authors say: "There are substantial gaps in published evidence for scale-up for five WHO-recommended TB interventions settings at country level, which for many countries possibly precludes program-wide implementation of these interventions."
They continue: "This lack of ''evidence for scale-up'' may be an important cause of the shortfall in implementation of these interventions in many countries."
The authors add: "There is a strong need for rigorous operational research studies to be carried out in programmatic settings to inform on best of existing and new interventions in TB control."