Remember meForgot password?
    Log in with Twitter

article imageTraining rats to sniff out TB sufferers

By Tim Sandle     Mar 30, 2016 in Science
East African researchers are considering using the highly developed sense of smell of rats to screen for tuberculosis among prisoners in the crowded prisons in Tanzania and Mozambique.
According to News Daily, African Giant Pouched Rats can be trained to sniff out a number of objects, from explosives to infections.
Tuberculosis is a major killer around the world, with many incidences on the increase (including a slight rise in the U.S. based on new Centers for Disease Control and Prevention figures.)
Tuberculosis is a widespread infectious disease caused by various strains of mycobacteria, typically Mycobacterium tuberculosis. The symptoms of infection consist of a chronic cough with blood-tinged sputum, fever, night sweats, and weight loss. Tuberculosis is closely linked to both overcrowding and malnutrition.
One region where tuberculosis levels are very high is East Africa and given that the disease spreads readily in crowded places, prisons are a place where transmission can happen quite rapidly.
An effective tuberculosis detection system will be both sensitive and specific. The purpose of any such detection system will be to classify people into two discrete categories: those who have the disease and those who do not. According to microbiologist Alan Poling: “the sensitivity of a given test refers to its ability to do the former; whereas its specificity refers to its ability to do the latter.”
If it is known that a prisoner is carrying the diseases, then it is possible to isolate the individual and prevent others from becoming infected. However, screening techniques are expensive and slow. This is where the idea of using rats comes in. A laboratory analyst can take up to four days to detect tuberculosis using standard methods; in contrast, a trained rat can screen 100 samples in 20 minutes and correctly identify which samples contain the bacterial infection.
Based on funding from the United States Agency for International Development (USAID), health authorities plans to recruit and train rats to carry out prison screening. Early tests suggest that the method is successful.
The training is being conducted by the Belgian charity APOPO (Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling.) APOPO's mission is to develop detection rats technology to provide solutions for global problems and inspire positive social change.
The African giant pouched rat (Cricetomys gambianus) is a large, nocturnal pouched rat that can grow up to 3 feet in length. The rat has poor eyesight, although this is compensated by a highly developed sense of smell and hearing.
With the training of the rats, the rodents learn to recognize the presence of tuberculosis in samples of sputum. On completion of the training, rats can be shown a row of 10 sputum samples (some disease free, some containing the bacterial infection.) When a rat detects tuberculosis it hovers over the sample for 3 seconds.
Speaking with The Guardian, Charlie Richter, APOPO’s U.S. director, stated: “We believe our unique TB Detection Rat technology will prove itself as an effective mass-screening tool.”
Further trials are underway. If successful, the rats will be introduced for the screening of prisoners in Tanzania and Mozambique later this year.
More about Tuberculosis, Rats, Prision, mycobacterium, mycobacteria
More news from
Latest News
Top News