Global south's TB diagnostics innovations are key to fight the epidemic

After years of reliance on donor funding, many high TB burden countries now face a stark reality: As G7 nations slash aid, they must do more with less. But there's a silver lining. Innovations developed in the global south — such as affordable molecular tests, tongue swab sampling, and AI-powered screening tools — are ready to drive equitable TB diagnosis at scale. Before the COVID-19 pandemic, tuberculosis was the leading infectious killer among humans. For a few years, COVID-19 took the top spot. Today, TB is back as the leading infectious cause of mortality, claiming 1.23 million lives in 2024. And things are likely to get worse due to cuts to development assistance by the Group of Seven leading industrialized nations. A recent analysis done across 26 high-burden countries, which account for 80% of the global TB burden, showed that termination of aid funding could result in as many as 10.6 million additional TB cases and 2.2 million additional TB deaths during the period 2025-2030. With donor funding declining, the burden of sustaining TB services is likely to fall on governments of high TB burden countries that will need to test and treat more people with potentially fewer resources. This was recently reinforced in a Devex article by the health ministers of four of the largest high TB burden countries: “To end TB, time for us to own our disease response and financing for health.” One way to support this transition is to innovate and develop more affordable and impactful new tools and accelerate the pace of our fight against the disease. Improving diagnosis remains a critical need, as each year, 2.4 million people with TB are “missed” by health systems— undiagnosed or unreported — allowing the world’s deadliest infectious disease to persist across communities. Currently, the most widely used molecular test, Xpert MTB/RIF, continues to be expensive and hard to implement at the level of primary care. We urgently need testing options that can be easily decentralized and be less reliant on sputum, a sample that not all people with TB can produce. We also need diagnostics to be manufactured in the global south, at affordable prices. Thankfully, all of these are now a reality. Investments in the innovation ecosystem by global south countries are starting to pay off. Affordable, locally produced solutions have emerged, with examples such as molecular technologies — e.g., MiniDock by Pluslife from China; Truenat MTB and Ultima by Molbio Diagnostics from India; UniAmp and Quantiplus® MTB by Huwel Lifesciences from India; Pathodetect by MyLab from India; TB-LAMP from Japan; ultraportable digital X-ray hardware by several companies in Asia; AI-assisted detection and care management tools, such as Qure.ai, DeepTek from India, Lunit from Korea; urine antigen detection tests, such as FujiFilm from Japan; and improved infection testing, such as SIILTBICY from India, or Wantai TB-IGRA from China. Driving up access to diagnostics and screening tools In particular, innovative work has been done to develop the use of tongue swabs as another option for collecting samples that would enable TB testing outside of traditional TB clinics, in primary care and community settings where most people seek care. Given the sizeable proportion of people with TB who cannot produce sputum, easy-to-collect samples such as tongue swabs can help reach more people, and detect more cases with opportunities to start treatment on the same day. In parallel, R&D has resulted in lower-cost, near point-of-care tools developed by companies in the Global South. China’s PlusLife MiniDock — recently added to The Global Fund to Fight AIDS, Tuberculosis and Malaria’s Expert Review Panel for In Vitro Diagnostics list for procurement — is a small, portable, affordable technology that is capable of diagnosing multiple diseases, with 90% cheaper instruments and test kits priced at just $3.60. Alongside noninvasive sampling such as tongue swabs, it makes testing easier for patients and more efficient for health systems. Similar class products are also available from India, and UniAmp has been validated for use on tongue swabs by the Indian Council of Medical Research. The World Health Organization is expected to offer policy guidance on this class of products soon. Along with diagnostics, use of digital data systems such as Ni-kshay 2.0 from India has brought public and private sectors together in a single digital TB register, improved case notification, patient engagement and support, including direct benefit payments, supported adherence monitoring and data transparency, offering the option for lab results to be rapidly linked to patient records. Ensuring that front-line primary care providers — public and private — are equipped with tongue swabs and point-of-care tests will lead to wider coverage of quality TB diagnostic services. They will also allow community-based screening and active case finding. Earlier this year, India carried out a 100-day active case finding campaign that led to the notification of over 700,000 TB cases. Integrated testing for multiple diseases In the era of universal health coverage, it is hard to justify separate labs, machines, and staff for separate disease conditions. As molecular testing can detect multiple infectious diseases, its use could enable a diverse range of tests to be carried out simultaneously — for example, TB, HIV viral load, COVID-19, sexually transmitted infections, respiratory syncytial virus, influenza, and HPV, to name just a few. To enable and optimize this, countries can employ tools such as diagnostics network optimization, DNO, and use the existing infrastructure for multidisease rather than single-disease testing, and identify the right sites for deployment of new tools. India has actively adopted DNO to optimize nucleic acid amplification test services across the country. After years of research, we now have innovations that are more affordable, context-specific, and able to be decentralized. These innovations blend technology, local manufacturing, and health system integration. High TB burden countries must adopt this newfound capacity to address the massive diagnostic gap that is preventing them from ending the TB epidemic. With rapid uptake of novel and affordable solutions, high-burden countries can and must take a leadership role, invest more domestic funds — for example, India’s TB program has significantly increased funding over the past few years — revolutionize TB care, and sustain momentum toward ending TB. Disclosures: None of the authors has personal industry conflicts or financial interests in any products or services described. Sameer Kumta works for the Gates Foundation, a nonprofit fighting poverty, disease, and inequity around the world, which has supported funding of a wide range of technologies through its global access commitment requirements. Madhukar Pai serves as an adviser to nonprofit organizations such as WHO, the Gates Foundation, and Partners In Health.