Sample Transport Medium

India’s National TB Elimination Program (NTEP) has expanded access to nucleic acid amplification testing (NAAT) platforms such as CBNAAT/Truenat, enabling rapid and accurate TB diagnosis. However, the impact of these technologies is often limited by conventional sample collection, preservation, and transport practices, which are unable to consistently maintain the quality of specimens from peripheral sites to testing laboratories.

Shortcomings of Existing Preservation and Transport Systems

Despite standardized guidelines, several persistent challenges reduce the effectiveness of current sputum sample logistics:

1. Sample Degradation: Sputum specimens often deteriorate during long transit, especially when cold chain conditions are not maintained, leading to false negatives and repeat testing.
2. Cold Chain Dependency: Transport media such as CPC (cetylpyridinium chloride) and other preservatives require temperature control to maintain viability, which is difficult to sustain in rural and remote areas.
3. Leakage and Contamination Risk: Conventional containers and manual handling increase the chance of spills, contamination, and biosafety hazards during transit.
4. Delayed Turnaround: Transport from peripheral health facilities to NAAT hubs can take 1–3 days, particularly in hard-to-reach tribal and high-burden areas, delaying diagnosis and treatment initiation.
5. Operational Burden: Multi-step packaging, courier dependence, and repeated follow-ups increase workload for health workers and raise costs for the program.
6. Limited Specimen Flexibility: Sputum dependence creates barriers for children and patients unable to produce adequate samples, further delaying testing.

Emerging innovations include:

1. Point-of-care sample processing devices (e.g., rapid lysis buffers like Truelyse) that stabilize and prepare samples for NAAT testing directly at the collection site, eliminating the need for a cold chain.
2. Advanced sample transport media and cards, such as the TB Send Card from Wobble Base Bioresearch, which allows safe, ambient-temperature transport of TB specimens while preserving nucleic acid integrity.
3. Dry storage and preservation solutions like BiomLife, which maintain DNA/RNA stability without refrigeration, extend sample viability during transit.
4. Integrated Sample Collection Kits like truGnom from Ruhvenile Biomedical OPC Pvt Ltd are designed to simplify collection, inactivate infectious agents, and ensure sample integrity for downstream NAAT testing.
5. Alternative specimen types (e.g., tongue swabs, urine, stool-based assays) that are easier to collect, safer to transport, and less prone to degradation.
6. Drone-based transport for rapid, reliable movement of specimens and cartridges from remote sites to testing hubs, reducing transport time to less than 2 hours.

These innovations can dramatically reduce sample-to-result turnaround times, maintain sample integrity, and improve case detection rates, particularly in underserved regions.

Conclusion

Overcoming the shortcomings of current sample preservation and transport systems is critical to closing the diagnostic gap and ensuring timely TB care. By adopting innovative collection, stabilization, and transport solutions such as TB Send Card, BiomLife, truGnom, Truelyse, and drone-based logistics, NTEP can reduce diagnostic delays, maintain sample quality, and move closer to India’s goal of a TB-free nation.