Dr Dog: How beagle Cliff can sniff C. Diff (video)

He has 83pc success rate in sniffing out hospital superbug after only two months' training

He is the hound of the hospital ward. Cliff, a two year old beagle with trademark floppy ears, has been trained to sniff out patients infected with a superbug and could potentially save hundreds of lives.

Instead of tracking hares, rabbits and other small game, Cliff puts his nostrils to work on the wards chasing down patients suffering from Clostridium Difficile, the hospital infection that can spread rapidly among the elderly causing lethal outbreaks.

Existing laboratory tests to diagnose the condition are expensive and slow and can delay the start of treatment by up to a week. Using a dog with a sensitive nose to patrol the wards and pick out infected patients is fast, efficient - and popular.

As a scent hound the Beagle has few equals – it can find a mouse in a one acre field in less than a minute. In tests, Cliff correctly identified 25 out of 30 patients with C Difficile – an 83 per cent success rate – and 265 out of 270 negative controls, after just two months training.

Unlike the lab technicians, he could screen a complete hospital ward in less than 10 minutes, strolling past each patient’s bed until he came to one with an infected occupant. Then he promptly sat down.

Despite his interest in their personal aroma, patients welcomed his visits. “He brings a lot of joy to the hospital. Patients love to see him,” said his owner.

The tests were carried out at two hospitals in Amsterdam which, in common with hospitals in the UK and around the world, have made strenuous efforts to reduce C Difficile rates. The infection occurs in older people who have been treated with antibiotics, disrupting the balance of bacteria in their gut and causing diarrhoea which in the worst cases can lead to bowel inflammation and death.

Major outbreaks in the UK at Stoke Mandeville and Maidstone and Tunbridge Wells hospitals in the mid-2000s, and smaller outbreaks at other hospitals, have claimed hundreds of lives.

Details of Cliff’s performance are published in the British Medical Journal by Dutch researchers from the University Medical Centre in Amsterdam who say it holds “great potential” for screening hospitals for C Difficile.

His owner, Hotsche Luik, describes in an accompanying video how she trained Cliff by hiding a plastic phial containing a small stool sample from a patient with C Difficile in a field. Cliff finds it without difficulty.

She repeats the test by hiding the phial on the saddle of a bicycle left amongst hundreds of others in racks in a busy city centre. Again, Cliff identifies the correct bike by sitting down next to it.

“Our nose is only good for holding glasses,” Ms Luik explains. “A well trained dog can sniff 500-600 times better.”

Writing in the BMJ the researchers say: “For the purposes of detection the dog did not need a stool sample or physical contact patients. It would seem dogs can detect C Difficile in the air surrounding patients.”

Previous research has shown that dogs can detect cancers, including those of the bladder, breast, bowel and skin, when given a sample of malignant tissue. In 2011, Japanese researchers described a labrador retriever called Marine, which had worked as a water rescue dog saving people from drowning by dragging them to shore,  which was successfully trained to distinguish the smell of a dozen different cancers.  But this is the first study in which a dog has detected disease in a patient, rather than a sample.

The Dutch researchers admit there may be one drawback to their strategy: using a dog to detect infections in hospital could end up spreading them.