How APOPO’s detection rats connect mine clearance and tuberculosis screening

How APOPO’s detection rats connect mine clearance and tuberculosis screening | Photo: APOPO

Published on 15 August 2026 at 04:57 GMT

By Editorial Team SDG3

African giant pouched rats have become an unusual part of two very different public-interest systems: clearing explosive hazards left by war and finding additional tuberculosis cases missed during routine testing. APOPO, a Belgian-founded non-profit with operational headquarters in Tanzania, trains the animals for both tasks. The shared principle is scent detection, but the consequences of an alert are determined by trained people, laboratory procedures, national authorities and formal quality controls.

The organisation’s work offers a practical example of how animal scent detection can supplement established methods without replacing them. In mine action, a rat’s indication leads to investigation by qualified deminers. In tuberculosis programmes, sputum samples indicated by rats undergo confirmatory testing before a patient is reported for treatment. The distinction matters because neither a scratch on the ground nor a pause over a sample is, by itself, a clearance decision or a clinical diagnosis.

From explosives to public health

APOPO emerged from research begun in the late 1990s into whether the strong sense of smell of African giant pouched rats could be used for humanitarian purposes. The animals are commonly known through the organisation’s HeroRAT label. They are conditioned through positive reinforcement to identify a target odour and communicate a finding through a learned behaviour.

Mine detection rats search prepared areas for vapour associated with explosive ordnance. Their low body weight means they can move across contaminated ground without exerting the pressure typically required to trigger an anti-personnel mine. They also respond to odour rather than metal, an operational advantage in places where fragments, coins and other scrap can produce repeated metal-detector signals.

The rats form one component of a wider land release process. Teams first examine records and consult communities to establish whether credible evidence of contamination exists. Suspected areas can then be surveyed using a combination of vegetation-clearing machinery, animal detection systems and manual deminers. When a rat indicates a location by scratching the surface, the point is marked. A human deminer subsequently investigates, identifies the item and arranges its removal or destruction.

This division of labour is reflected in the International Mine Action Standards. The standards recognise dogs and rats as animal detection systems that may support technical survey and clearance, while requiring external accreditation, operational testing and continuing quality management. The system includes handlers, supervisors, procedures, veterinary support, performance data and national oversight, rather than treating the animal as a standalone instrument.

Conditions also limit deployment. APOPO reports that mine detection rats require vegetation to be removed so handlers can maintain line of sight, and that the animals are not suited to cold climates. Terrain, contamination density, national accreditation and the availability of other assets therefore shape where the method is used. The organisation’s 2025 annual report describes mine-action operations that combine rats and dogs with conventional demining techniques in countries including Angola, Azerbaijan and Cambodia.

For communities living beside suspected minefields, the relevant outcome is not the novelty of the detector but whether land can be released under an accredited process.

Explosive contamination can restrict farming, movement, access to water and infrastructure long after fighting has ended.

Clearance can reopen land, although post-conflict recovery also depends on land tenure, services, finance and local security.

A second screening layer for tuberculosis

The tuberculosis programme applies the same olfactory capability in a controlled laboratory setting. Clinics collect sputum from people being investigated for pulmonary TB and test it using routine methods. Samples are transported to an APOPO laboratory, heat-treated for safety and presented to trained rats. Samples indicated by the animals are then checked with an approved confirmatory test. Only confirmed results are communicated through the health system.

A 2025 peer-reviewed study in PLOS ONE examined 43,153 samples from 34,565 people attending 69 health facilities in Tanzania in 2023. It evaluated the incremental yield of rats after initial smear microscopy or Xpert MTB/RIF testing. The study reported that the rats identified additional samples later confirmed as TB-positive, with an incremental yield of 44 per cent at Xpert facilities and 59 per cent at smear facilities in the analysed groups. The additional yield was lower where the more sensitive molecular test was already in use.

The authors concluded that the trained rats added case-finding value within the studied programme, while their results also underline the technology’s role as a supplementary screen. The study was conducted by researchers affiliated with APOPO and partner institutions, and its funders were reported as having no role in study design, analysis or publication. Broader assessments in other settings remain relevant to decisions about generalisability and programme design.

The World Health Organization estimated that 10.7 million people developed TB in 2024 and that 1.23 million died, including people with HIV. Its 2025 reporting identifies persistent gaps in access to rapid molecular diagnostics and in bacteriological confirmation. WHO guidance prioritises recommended rapid diagnostic tests because they can detect TB and, in some cases, drug resistance. Detection rats are not listed as a WHO-recommended diagnostic test, which places APOPO’s operational model alongside, rather than in place of, nationally approved diagnostic pathways.

That boundary is especially important for drug-resistant TB. Smell-based screening does not establish resistance to medicines. Molecular testing, culture or sequencing is required for that purpose. The rats may help flag samples for further attention, but clinical decisions remain with health services using validated diagnostic procedures.

One technique, two systems

The two programmes connect to SDG 3 (Good Health and Well-being) through the prevention of injury from explosive hazards and the detection of a major infectious disease. The link does not make mine clearance and TB screening interchangeable. Each has different evidence requirements, regulators, risks and definitions of success.

APOPO’s detection rats illustrate both the attraction and the constraint of specialised innovation. An animal can rapidly screen ground or samples for a learned odour, but the public-interest result depends on the surrounding system. Accreditation, confirmatory testing, trained staff, transparent performance data and long-term funding determine whether an alert becomes safe land or a correctly managed TB case.

Further information:

APOPO Annual Report 2025, used for the organisation’s current programme model, operational locations and integration of animal detection with conventional methods. https://apopo.org/wp-content/uploads/2026/06/APOPO_AR-2025-fin.pdf

PLOS One, “The incremental value of tuberculosis detecting African giant pouched rats over smear microscopy and Xpert MTB/RIF for Tanzanian TB detection”, used for the 2025 Tanzania study design, results and limitations. https://doi.org/10.1371/journal.pone.0321866

World Health Organization, Global tuberculosis report 2025, used for current global TB estimates and diagnostic context. https://www.who.int/teams/global-programme-on-tuberculosis-and-lung-health/tb-reports/global-tuberculosis-report-2025

International Mine Action Standards 07.31, used for accreditation and operational-testing requirements for mine detection rats and other animal detection systems. https://www.mineactionstandards.org/standards/07-31/