New pooled testing toolkit to help expand TB diagnosis to ‘missed millions’ 

A new pooled TB testing toolkit will help healthcare providers to reach the ‘missed millions’ who go undiagnosed with the disease each year.  

Evidence from Start4All, a four-year Unitaid-funded partnership led by Liverpool School of Tropical Medicine, has already shown that pooled sputum testing can cut costs and expand access to TB diagnosis without compromising accuracy.  

The findings have informed World Health Organization guidelines, and will now be part of a practical toolkit for National TB Programmes and others who are looking to implement or scale-up pooled testing.   

Dr Tom Wingfield, Principal Investigator on Start4All and Deputy Director of the LSTM Centre for TB Research at LSTM, said: “The launch of our Start4All pooled TB testing toolkit showcases the strength of this unique project’s research and partnerships in shaping global TB diagnosis strategies. Start4All’s evidence directly informed WHO’s 2026 pooled sputum testing guidelines and is now underpinning practical, open-access tools that can help National TB Programmes to expand equitable access to rapid TB testing, bringing diagnosis closer to communities while making better use of limited resources. This will contribute to more of the “missing millions” of people with TB starting treatment and, ultimately, becoming cured of TB.”

Start4All is delivered in collaboration with the Stop TB Partnership and eight partners across seven high TB burden countries, aimed at bringing TB diagnosis closer to communities most affected by the disease.  

Global efforts to tackle TB – a highly infectious disease that causes approximately 1.3 million deaths per year, more than any other single infection – are hampered by the large number of people sick with TB who remain undiagnosed, thereby going untreated and, unknowingly, able to spread TB in their homes and communities. Chronic underinvestment has led to limited and inequitable access to WHO-recommended molecular rapid diagnostic tests, which only one-in-two people globally receive as their initial test. 

By combining multiple sputum specimens into a single test cartridge, the new approach improves testing reach and maximises limited diagnostic resources, particularly in high TB burden settings in low- and middle-income countries, which are facing significant constraints.   

The newly released toolkit provides a set of practical resources designed to support the implementation of pooled sputum testing in routine settings.  

It includes a laboratory standard operating procedure that provides clear, step by step guidance to ensure that testing is conducted consistently and safely across sites, as well as a laboratory checklist to ensure that equipment and supplies are in place, as well as case studies to illustrate how pooled sputum testing has been implemented in real-world settings.  

The new toolkit marks a shift from proof of concept to real-world implementation of Start4All’s findings. In the next phase of the project, pooled testing will be combined with CAD-guided triage and expanded to tongue swab specimens, supporting simpler and scalable approaches that can expand access to molecular TB testing. 

The toolkit was launched at a special Start4All webinar on pooled sputum testing for TB diagnosis on April 16.