Brazzaville – Significant progress has been made in TB diagnostics in the past decade as countries in the African region embrace new technologies. However, many people still have no access to modern testing, which are often limited to major laboratories in large cities and leave out many due to high costs. Dr Jean de Dieu Iragena, a WHO expert on TB diagnostics in the African Region, discusses these technologies and how to bring them closer to people, so that challenges like multidrug-resistant TB (MDR-TB) can be properly managed and controlled.

What factors are impeding effective TB diagnosis in the African region?

Many rural and remote areas lack adequate healthcare infrastructure and essential diagnostic tools, for example, GeneXpert machines. There is also a significant shortage of trained health professionals, including laboratory technicians and tuberculosis specialists.

There are higher costs associated with TB diagnosis and often rapid, molecular diagnostic machines are only found in urban centres. Therefore, people in the remote areas often face longer travel distances to access these diagnostic services.  

Stigma and lack of awareness of TB prevents timely diagnosis and therefore treatment. We need massive campaigns across countries to help people better understand the disease, its implications, and to better learn about how quickly this disease can be diagnosed and treated. Stigma is based on the nature of the disease. TB is an infectious disease and someone who is infected might be subject to stigma from family, community and society. Its symptoms are unpleasant and hence someone who is very ill from the disease can be stigmatized.

What advances have been made in diagnostics and other key TB control measures in the region?

WHO has been doing a lot to advance diagnostic technologies to test for TB over the last 10 years. There are other traditional technologies like smear microscopy that miss a higher percentage of cases because they are unable to diagnose TB and drug-resistance early. The focus now is on rapid, molecular diagnostic methods, like GeneXpert, which can not only accurately detect TB but also the presence of drug-resistant TB in a sample. There are also other molecular diagnostic methods that have been endorsed for example, genome sequencing, which is really making progress in the speed of diagnosis. Other advances are related to screening methods. WHO has recommendations on the systematic screening of a higher-risk individuals who are most likely to have TB, which can accelerate early detection before symptoms appear.

WHO has made efforts to identify novel biomarkers – new indicators of the stage of disease that can help detect at an earlier stage – for more robust point of care tests, which are preferred because they can provide information on the nature of the disease close to the patient without having the patient to be referred to another laboratory, which is located in the big cities where most of the technologies are implemented. Governments have been working to make sure that those point of care diagnosis are available for the rollout and scale up at the country level.

What can countries and individuals do to avert MDR-TB?

There has also been major progress around enhanced TB treatment protocols. With multi-drug resistance, which has been affecting the African region, new regimens of medicines have been recommended to combat drug resistant TB strains, and those regiments includes shorter treatments, courses and new modifications. Countries are really required to uptake those treatment protocols to fight TB.

Of course, one size does not fit all and every technology has its advantage and it disadvantages, so the TB programme should do a needs assessment. Based on these requirements, there is a need to better identify technology that can fit in one or another setting, so that someone who is diagnosed with TB can also be diagnosed with a drug-resistance profile. This can help the clinician or the medical doctor to specifically prescribe the appropriate medicine, which will contribute to treatment success.

We need to ensure that once someone has symptoms, they are diagnosed early to avoid transmission of the disease and immediately put on the right treatment. This will help to cut the chain of transmission.

It is critical that the funding mechanisms for TB continue, to make sure that the gains from what has been achieved so far is not lost. If we do not invest in the laboratory system it will be more difficult to contain any pandemic or outbreak.