When Rat Is A ‘Hero’ And Reward A Banana: Tanzania’s Unique Way To Sniff Out TB, Landmines

Last Updated:September 14, 2025, 17:09 IST

How hero rats became front-line responders in Tanzania and beyond

A rat is rewarded after a successful search and rescue training mission in simulated earthquake rubble at APOPO's facility in Morogoro, Tanzania. (AP)

Finding survivors amid earthquake rubble, detecting explosives, tuberculosis (TB) to landmines, they can detect them all. This is what makes them the hero rats and front-line responders in Tanzania.

APOPO’s Training & Research Center based in Morogoro, Tanzania has been researching and developing the technology for 20 years. Here’s all you need to know.

FAQs from APOPO website: What makes them the heroes?

Landmines: A HeroRAT can search an area the size of a tennis court in 30 minutes – a human deminer with a metal detector can take up to 4 days

TB: A HeroRAT screens 100 sputum samples in 20 minutes. A lab technician using microscopy takes up to 4 days.

During the week, trained rats live on a reward diet that consists mainly of bananas, avocado and peanuts. They eat a balanced diet of grains, maize, fresh vegetables, fresh fruits, fish, nuts and rodent chow pellets.

How are the rats trained?

APOPO trains the rats using operant conditioning to shape and reward behaviour with a handheld clicker and food rewards. Training begins with socialising the rat to humans when its eyes first open around four weeks old.

APOPO’s trainers introduce the baby rats to the sights, sounds, and textures of the human world. The young rats are later weaned from their mothers at 10 weeks and begin clicker training, where they learn to associate a click sound with a food reward – usually a nutritious mix of mashed banana, avocado, and rodent chow.

Once the association is established, they are ready to begin training on a target scent of either TNT or TB-positive sputum. Once the rat learns how to signal to its handler that it smells the target odor, training complexity gradually increases to teach the rat to ignore irrelevant odours and to search for targets according to the needs of the operational environment. This training continues until the rat passes a blind test to earn its accreditation.

What are their training hours?

Normally, the rats are trained about half an hour per day, five days per week. During the weekend, they relax and can feast on an extensive variety of fresh foods.

What is the cost of training one of these rats?

€ 12 per month covers basic nutrition, daily care, housing and healthcare for one rat. Training, evaluation, and care costs an average of € 6,000 (Rs 530997.60) to fully train one detection rat.

How long do they live?

The hero rats live for around eight years. They can work in the field for up to four-five years.

Manjiri Joshi

At the news desk for 17 years, the story of her life has revolved around finding pun, facts while reporting, on radio, heading a daily newspaper desk, teaching mass media students to now editing special copies ...Read More

At the news desk for 17 years, the story of her life has revolved around finding pun, facts while reporting, on radio, heading a daily newspaper desk, teaching mass media students to now editing special copies ...

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