The complex factors that contribute to Clostridium difficile infection

Over the past decade Clostridium difficile has emerged as a serious public health issue, causing both hospital-based epidemics and community-associated disease. The most commonly recognised cause of antibiotic-associated diarrhoea in the human population, C. difficile was initially seen as a nuisance pathogen causing limited disease in the hospital setting. However, the emergence of 'hypervirulent' strain types, associated with an increase in both morbidity and mortality, has made it a pathogen of great concern worldwide. Infection with C. difficile is also being increasingly documented in animals, with suggestions that animals destined for human consumption may provide a reservoir for disease. The use of antibiotics is considered the main risk factor for the development of human infection; however, many other factors such as strain type, patient age, and host immune response all contribute to disease caused by C. difficile.