MSH Applauds New Rapid Tuberculosis Test

MSH Applauds New Rapid Tuberculosis Test

The World Health Organization (WHO) recently endorsed a new and novel rapid test for tuberculosis (TB), especially relevant in countries most affected by the disease, and is calling for widespread use of this test and its incorporation into national plans.

MSH applauds the research and development experts who developed this new TB test and the WHO for endorsing it so quickly. The test could revolutionize TB care and control by providing an accurate diagnosis in less than two hours, compared to current tests that can take up to three months to produce results.

Evidence suggests that use of this test could result in a three-fold increase in the diagnosis of patients with drug-resistant TB and a doubling in the number of HIV-associated TB cases diagnosed in areas with high rates of TB and HIV. Finally, the test is easy and safe to use and also allows for testing in non-health facility settings, including in people’s homes.

As with all new technologies, there are some challenges that need to be overcome to roll this new test out on a large scale. The negotiated price per test sounds reasonable, however similar negotiations for other diagnostic tests (HIV tests, CD4, etc.) have met with little success. While there are global negotiated prices through WHO and other agencies, there is still huge variation of cost of diagnostics in countries. Mechanisms to ensure countries access these negotiated prices have to be well thought through for this rapid test, and as recommended in the CD4 testing in developing countries, follow the medicine's design.

Temperature is another factor. While the technology can be implemented at any TB diagnostic center/management unit (TBMU), infrastructure considerations still need to be kept in mind because the test cartridges are stable at room temperatures (max 28 degrees C). Temperatures in tropical African, Mediterranean, Middle Eastern, and some Asian regions where the technology is needed often exceed 28 degrees C in some months of the year. More data is needed to confirm stability and performance of the reagents in such settings. Primary health facilities may not have refrigerators or air conditioners to maintain the required temperatures.

Another potential obstacle is storage space for the ‘mini-lab’ cartridges, which are quite bulky and will require considerable storage space to maintain enough stock even for a few months in any proficient TB unit. Classical TBMU in most high burden countries actually do not have dedicated store rooms for supplies and mostly make use of small cupboards and lockers to store supplies. Supply management issues require close consideration to ensure frequent deliveries of this single item. Supply chains in the countries have (or are the process) to harmonize schedules for delivery of health supplies based on individual country challenges. Instituting frequent delivery schedules may pose as additional hurdle to health systems in countries.

The GeneXpert equipment requires annual calibration. Proximity to countries of the equipment maintenance support is a practical challenge that must to be addressed from the start. The cost to TB programs to maintain hundreds of these machines will ultimately be an issue of discussion, particularly after demand for the technology has been created.

Other red flags to a large scale roll out of this new test include the cost of the machine, the daily through-put, whether the lab techs will need specialized training, whether the test is subject to user error, and whether continuous electricity is required.

These operational challenges provide an opportunity for stronger collaboration among TB control implementers and specifically to MSH with such vast experience of successfully implementing programs in challenging settings. If some or all of these issues are addressed, this test may revolutionize TB testing and finally bring TB testing into the 21st century.

Sara Holtz is MSH’s HIV & AIDS Initiative Manager. This blog post was based on comments from multiple HIV/TB experts at MSH.