Giant Rats are saving lives by sniffing out TNT in unexploded landmines as featured in National Geographic’s video of detector rats on the job in Cambodia(6). While people with metal detectors not only risk their lives in looking for unexploded landmines, we are slower than the rats. Rats can a 200 square meter area in 16-25 minutes, while humans take 2 -3 days with a manual metal detector (which pings at any metal). The rats specifically target only the TNT scent in explosives. Rest assured the rats are light enough to walk over the mines without setting them off. When they find TNT, they scratch to indicate. They don’t understand verbal cues, but they do enjoy food rewards. Trained dogs are also used, but they are larger, more expensive and more difficult to transport. These rats are making a difference, saving lives and improving the quality of life for local residents. APOPO Training Manger Abdullah Ramadhan captured the emotional impact, when he said “Being able to move around freely and not having to fear anymore was a great relief for everybody I met”.
A new area of study also found that trained scent detection rats are surprisingly efficient at detecting tuberculosis infections in children. In fact, they can be even more accurate than when hospitals analyzed sputum samples under a microscope(2). Tuberculosis (TB) is a serious infection that mainly affects the lungs(4). According to the World Health organization, as of 2018, TB is one of the world’s top 10 causes of death worldwide (1). In 2016, 10.4 million people became ill with TB and 1.7 million died. Most deaths occurred in low and middle-income countries. Unfortunately lab tests aren’t 100% accurate, and many children are missed, such as when they can’t produce enough saliva to analyze. Without treatment, it can be fatal.
Could millions more lives be saved through improved diagnosis using detector rats? TB emits a specific scent, which rats can be trained to detect, much like dogs can detect a variety of conditions from cancer to diabetic emergencies. A Tanzanian study (5) took a second look at 982 children whose saliva had been analyzed in laboratories. While the lab test found 34 children had TB, trained sniffer rats found 57 actually had the disease. The rat detection program enabled 70% more to be treated. Georgies Mgode, lead researcher, commented: “As a result, many children with TB are not bacteriologically confirmed or even diagnosed, which then has major implications for their possible successful treatment… There is a need for new diagnostic tests to better detect TB in children, especially in low and middle-income countries (3).
In conclusion, rats are a cost-effective option for scent detection of TB infection, and landmines. For the rats, it’s all about the rewards. For appreciative researchers and communities, it means that many lives are saved.
- Tuberculosis Key Facts, World Health Organization Fact Sheet. http://www.who.int/news-room/fact-sheets/detail/tuberculosis
- Mgode GF et al. “Pediatric tuberculosis detection using trained African giant pouched rats” in Pediatric Research, 84, 99-103 (2018). https://www.nature.com/articles/pr201840.pdf
- Rats sniff out TB in children, Elizabeth Hawkins, Springer Nature. Downloaded from https://www.springer.com/gp/about-springer/media/research-news/all-english-research-news/rats-sniff-out-tb-in-children/15596062
- Tuberculosis, Mayo Clinic, Patient Care & Health Information. https://www.mayoclinic.org/diseases-conditions/tuberculosis/diagnosis-treatment/drc-20351256
- Study: Rats Better at Detecting Tuberculosis in Children Than Standard Test, Ben Renner, Study Finds, April 10, 2018. Downloaded from https://www.studyfinds.org/rats-better-detecting-tb-tuberculosis-children/
- Rachel Becker, Meet the Giant Rats That Are Sniffing out Landmines. National Geographic, Oct. 2015. https://news.nationalgeographic.com/2015/10/151006-giant-rats-landmines-cambodia-science-animals/