Giant Rats Are Helping Doctors in Mozambique Sniff Out Tuberculosis

According to the Global Tuberculosis Report nearly 20,000 people die from TB every year in Mozambique and most of those who are infected never know they have the disease. Dr. Emilio Valverde, a tuberculosis expert with the Belgian aid organization APOPO, trains African giant pouched rats to sniff out tuberculosis. The cat-sized creatures — each about a foot long and weighing roughly 10 pounds — use their keen sense of smell to detect the presence of tuberculosis in saliva samples.

Here's how it works:

• The scientists use a clicker — similar to the tool commonly used for dog training — to create an association between food and the clicking noise.
• Once the rat associates the clicker sound with a treat, it begins training on scent discrimination. The rat is offered choices of negative and positive TB samples placed under sniffer holes.
• When the rat pauses above a positive sample, a lab technician will sound the clicker. The rat then goes the corner of its cage and awaits a treat.

Read more about how these rats are saving lives: VICE News