Progress in the fight against TB is not sufficient to reach global goals. The 2020 WHO Global TB Report shows little change since the previous year. Nearly 1.4 million people died from TB in 2019. Of the estimated 10 million people who developed TB that year, approximately 3 million were either not diagnosed, or were not officially reported to national authorities.[1] TB continues to be one of the greatest infectious disease killers in the world, especially of the most vulnerable. Despite recent advancements in treatment and diagnosis, existing tools are inadequate and/or underutilized to close the gap in identifying missing cases.
In addition, the COVID-19 pandemic has started to undo progress made to date. There are major disruptions to TB programs and supply chains and substantial reductions in numbers of individuals being diagnosed and seeking care.[2],[3] COVID-19-related lockdowns have limited the mobility of people and access to healthcare, highlighting the need to bring care closer to those in need. In this context, there is a need for rapid diagnostic tools that can test for many pathogens and be implemented in primary healthcare settings including local health clinics, medical offices, health posts, or by community health workers during home visits. Advances in contact tracing and diagnosis for COVID-19 provide opportunities for adaptation and leveraging of such tools for TB.
Recent research and evidence on the patient pathway for TB highlight gaps in care often at the first point of contact with the health system, where affected individuals are not served adequately or are lost to follow-up. This leads to delays and misdiagnoses which translate to wasted resources, high costs for both the individual and the system, poor health outcomes, drug resistance, and onward transmission. [4],[5] TB diagnosis remains the weakest link in the TB cascade of care. Often, those affected by TB must interact with the health system many times before receiving accurate diagnosis and appropriate care.
Without substantial intervention to address the gap in finding missing TB cases, TB transmission will remain out of control, perpetuating the TB epidemic, leading to continued morbidity and mortality. This gap in case detection is in part due to inadequate uptake and national scale-up of existing WHO recommended TB diagnostic tools. Furthermore, many of these existing diagnostic tools fail to sufficiently meet the needs of people at risk of TB or of health systems in terms of accuracy, time to results, affordability, and appropriateness for use at the lowest health care levels.[6],[7] Existing tests with their complexity and cost are centralized mostly at secondary and tertiary levels of the health system. Some of this complexity is the heavy reliance on sputum samples, often difficult to obtain especially from children, to obtain bacteriological confirmation. There is a need to address the key barriers to providing true point-of-care solution for TB detection, including lack of infrastructure (e.g. unreliable power supply in remote settings), need for sputum samples, need for specialized laboratories and technicians, high testing and maintenance costs, and lack of robustness in rural and tropical settings.
Through this call for proposals, Unitaid aims to catalyse access and optimal introduction and placement of effective tools for the timely and accurate detection of TB.
[1] WHO Global TB Report 2020,
[2] http://www.stoptb.org/news/stories/2020/ns20_014.html
[3] https://www.theglobalfight.org/covid-aids-tb-malaria
[4] Conducting Patient-Pathway Analysis to Inform Programming of Tuberculosis Services, JID 2017:216 (Suppl 7). http://stoptb-strategicinitiative.org/wp-content/uploads/2018/07/Conducting-PPA-to-inform-TB-Services.pdf
[5] TB patients endure tortuous pathways and broken care cascades by Madhukar Pai. https://naturemicrobiologycommunity.nature.com/posts/22350-tb-patients-endure-tortuous-pathways-broken-care-cascades
[6] Treatment Action Group TB Diagnostic Pipeline Report 2020
[7] TAG’s an Activist’s Guide to Tuberculosis Diagnostic Tools