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Lab Rats Save Lives

Lab rats are being trained to detect a deadly disease called tuberculosis.

A rat in an enclosure sniffs a slide as a woman in a lab coat observes.

Courtesy of APOPO

An APOPO rat that has been trained to detect tuberculosis sniffs saliva samples for signs of the disease.

When you hear the term “lab rat,” you may picture a rat running through a maze while scientists in lab coats take notes for research. Specially trained lab rats in Tanzania and Mozambique have a different job. They help their human colleagues detect a deadly infectious disease.

The African giant pouched rat isn’t just the largest rat species in the world. It also has a keen sense of smell, which people have realized could be useful for detecting things that humans and machines cannot. An organization called APOPO has trained some of these rats to detect tuberculosis (TB), a bacterial disease that affects the lungs and causes coughing, difficulty breathing, and chest pains.

TB spreads quickly and can be deadly if left untreated. The World Health Organization says that 10 million people around the world get sick with TB each year. Fortunately, medicine and antibiotics can treat TB if it is caught in time. This is where the helpful lab rats, which APOPO calls HeroRATs, come in.

A man wearing a rubber glove holds up a slide containing a saliva sample.
Courtesy of APOPO

A lab technician shows a slide with a saliva sample that is being used in APOPO’s tuberculosis detection program.

Here’s how the rats do their job: a doctor sends patient saliva samples to a laboratory for testing, where human lab technicians perform an initial screening with bacteria-detecting tools. Afterward, the HeroRATs do a sniff test of the samples to “double check” whether any TB-containing samples have been missed. In many cases, the rats can identify samples where the bacterial amounts are too small for conventional laboratory tools to detect.

As a result, the rats have been successful in helping humans identify TB patients who would otherwise be missed. APOPO reported that its HeroRATs increased the TB detection rate by 48 percent in facilities in Tanzania. In other words, the HeroRATs detected an additional 2,176 TB patients, meaning thousands of sick people received treatment for the disease so that they would not spread it to others.

A man smiles and looks at a rat that he is holding up to the camera.
Courtesy of APOPO

An APOPO employee holds one the African giant pouched rats that have been trained to detect signs of danger.

Since APOPO began this work, HeroRATs have detected enough missed cases to prevent more than 300,000 possible TB infections.

“One untreated person can infect 10-15 people, [so] multiply that by 24,000 people correctly treated, who had been missed through regular tests,” Joseph Soka, a manager at APOPO’s laboratory in Dar es Salaam in Tanzania, told The Guardian. “These were not just samples, these were lives saved.”

Experts don’t expect the HeroRATs to fully replace conventional TB detection methods, but the animals are showing promise as a tool to help the human experts identify patients and fight the spread of disease.

Did You Know?

APOPO has also trained African giant pouched rats to sniff out dangerous situations in war zones and help find people trapped in buildings after earthquakes.  

A brown rat wearing a tiny backpack walks down a wood plank that leads from a window to a room with cement brick walls and containing tires.

Courtesy of APOPO

An APOPO rat climbs into a building during a search and rescue training session.

Dogs with Jobs

A white dog wearing a service dog harness uses a cord to pull a gate closed as a man in a wheelchair looks on.

© 24K-Production/stock.adobe.com

Dogs make great pets and companions, but some dogs have jobs! Service dogs are trained to perform tasks for people with disabilities or those who need medical support. Here are some types of service dogs you may encounter while in public:

  • Guide dogs: Possibly the most recognized type of service dog, these dogs are trained for people who have visual impairments. Guide dogs help people avoid obstacles as they travel between destinations. They can even look out for traffic!
  • Hearing dogs: Similar to guide dogs, hearing dogs use their sense of hearing to help those who may be deaf or hard of hearing navigate the world. They can alert their owners when they hear sounds like doorbells, knocking, or smoke alarms.
  • Medical alert dogs: Dogs that can perform medical alerts use their sense of smell to sense chemical changes in a person’s body. 
    • Diabetic alert dogs can sense if someone’s blood sugar is too high or too low.
    • Seizure response dogs can assist people with epilepsy, guarding them or finding help if their owner is having an episode. Some dogs are trained to lie next to or on top of their owners to help apply pressure to the person’s body while they are seizing or unconscious.
  • Mobility assistance dogs: These dogs help people with physical disabilities from brain injuries, arthritis, or cerebral palsy. Mobility assistance dogs can open doors, turn on lights, and retrieve a variety of necessary objects to make life easier for their owners. Some are specially trained to help owners who use wheelchairs.

Service dogs often wear special harnesses that indicate their job as an assistance animal. Never pet or interact with a service dog while it’s working. Distractions could be dangerous if they prevent a service dog from providing a medical alert in time or avoiding an obstacle in its owner’s path. 

Even when a service dog doesn’t appear to be doing anything, it’s still working and doing its job! Service dogs get to play when they take breaks.

Why Are Some Animals Pets?

A woman hugs a small goat wearing a tag reading Gizmo in a park setting with a few other people in the background.

© Araya Doheny/Getty Images

Humans have domesticated, or tamed, a variety of animals to provide food or clothing, to perform tasks, and to keep us company as pets. But not all animals can be domesticated, and some can be tamed more than others. Find out why at Britannica!

WORD OF THE DAY

reinforcement

PART OF SPEECH:

noun

Definition:

: the act of strengthening or encouraging something

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