The Dutch researchers said that trained animals could screen hospital wards to prevent C.diff outbreaks.
They trained a two-year-old male beagle called Cliff to identify the infection.
After two months of training, Cliff's detection abilities were tested on 50 stool samples from infected patients and 50 normal samples.
He correctly identified all 50 positive samples and 47 out of 50 negative samples.
He was also tested in a hospital setting -- and identified 25 out of 30 infected patients and 265 out of 270 patients who did not carry the infection.
Screening took just 10 minutes to detect the presence of C.diff in patients on the ward.
The authors wrote: "It is feasible to use a dog to detect Clostridium difficile in stool samples and in patients.
"The dog's diagnostic accuracy with stool samples suggests that immediate identification of C.difficile is possible. Moreover, our data suggest that the same may be true for the rapid diagnosis of C.difficile infection on clinical wards.
"The dog did not need a stool sample or physical contact with patients.
"It would seem dogs can detect C.difficile in the air surrounding patients.
"In addition, dogs are quick and efficient: patients in a hospital ward can be screened for the presence of C.difficile infection in less than 10 minutes."
C.diff is the most common bacterial cause of infectious hospital-acquired diarrhoea in developed countries. It can cause diarrhoea ranging from mild symptoms to a very severe illness and can be fatal.