Dogs Can Sniff Out ‘Superbug’ Infections
Researchers see potential for screening hospital wards (Dec. 13)
Dogs can sniff out Clostridium difficile (the infective agent responsible for many hospital-acquired infections) in stool samples and even in the air surrounding patients in hospitals with a high degree of accuracy, according to a study published in the British Medical Journal.
The findings support previous studies of dogs detecting various types of cancer and could have potential for screening hospital wards to help prevent C. difficile outbreaks, say the authors.
In a proof-of-concept study, two Dutch teaching hospitals investigated whether a dog’s superior olfactory sensitivity could be used to detect C. difficile in stool samples and in 300 hospitalized patients (30 with C. difficile infection and 270 controls). A 2-year-old beagle trained to identify the smell of C. difficile was guided along the wards by its trainer, who was unaware of the participants’ infection status. Each detection round involved 10 patients (one case and nine controls). The dog was trained to sit or lie down when C. difficile was detected.
The dog’s sensitivity and specificity for identifying C. difficile in stool samples were both 100%. During the detection rounds, the dog correctly identified 25 of the 30 cases (sensitivity, 83%) and 265 of the 270 controls (specificity, 98%).
The authors conclude that a trained dog can detect C. difficile with high estimated sensitivity and specificity, both in stool samples and in infected patients, in a hospital setting. They further suggest that this finding could have potential for screening for C. difficile infection in healthcare facilities and thus could contribute to the control and prevention of outbreaks.
The authors acknowledge, however, that the use of dogs in hospitals might pose a risk to the dogs themselves, to hospital staff, and to patients. “Dogs can be carriers of C. difficile strains and other pathogens,” they write. “Similar to hospital staff, the dog could be a source of transmission. This risk could be minimized by using strict preventive measures, such as avoiding physical contact with patients and their surroundings.”
Source: BMJ; December 13, 2012.