Between 2001 and 2006, epidemic of the bacterium Clostridium difficile infection (CDI), appeared as severe disease form when it is caused by a hypervirulent strain characterized as North American ribotype 027; this strain has caused outbreaks of CDI in the United States, Canada, and Europe. The first reports of outbreaks of CDI due to type 027 originated from Canada, where Quebec was most severely affected. In the United States, CDI due to type 027 has been reported from at least 38 states. In addition, the European Centre for Disease Prevention and Control reported infections due to type 027 in 16 European countries.
Clostridium difficile which inhabit the bowel and cause dangerous diarrhoea, and most of the strains originated from a single lineage of C. difficile known as ribotype 027, which has now spread around the world. Of particular concern has been the correlation between RT027 and a dramatic increase in deaths related to C. difficile. The mystery of why this ribotype and a second one, RT078, became so prevalent apparently out of thin air has remained largely unsolved. Collins and his colleagues from Baylor College of Medicine Texas found that the seemingly harmless addition of a sugar called trehalose to the food supply contributed to this disease epidemic. These two strains can use low concentrations of trehalose as a sole source of carbon. They analysed the genomes of RT027 and RT078, and discovered that each encodes unusual sequences that might explain their ability to grow in low levels of trehalose.
Collins and colleagues propose a surprising answer. Before 1995, high production costs made trehalose untenable as a food additive. But manufacturing innovations reduced the cost of trehalose production more than 100-fold8, and the US Food and Drug Administration and European agencies approved the sugar as a safe food additive in 2000 and 2001, respectively
Trehalose is now added to a variety of food products, including pasta, ice cream and minced beef and supplementing the food supply with trehalose preceded the C. difficile outbreaks. They therefore suggest that the addition of trehalose to the food supply might have increased the sugar in the human bowel to levels high enough to enable growth of these ribotypes.
" It is impossible to know all the details of events surrounding the recent C. difficile epidemics, but the circumstantial and experimental evidence points to trehalose as an unexpected culprit. "