Researchers have identified a protein in saliva that protects the body from traveller's diarrhoea a finding that may lead to the development of new preventive therapies for the disease. Traveller's diarrhoea is a digestive tract disorder that commonly causes loose stools and abdominal cramps. The findings showed that the protein histatin-5 in human saliva helps the body defend itself from the gut infection. According to the US Centres for Disease Control and Prevention (CDC) estimates up to 80 per cent of cases of travellers' diarrhoea are caused by bacteria. The most common bacterium that causes travellers' diarrhoea is enterotoxigenic Escherichia coli (ETEC)