Prevention of Clostridium difficile infections-The role of vaccines and therapeutic immunoglobulins

Clostridium difficile is a spore-forming gram-positive bacterium that causes sometimes severe infections of the gut of affected individuals. The high prevalence of C. difficile infections has caused the Center for Disease Control to characterize this disease as “an immediate health threat that requires urgent and aggressive action.” A major issue with existing treatments for C. difficile is their reliance on antibiotics to kill the bacterium. These antibacterial agents cause disruptions in the gut flora that normally compete with C. difficile, rendering the gut lumen susceptible to a new round of infection or to germination of persistent C. difficile spores. This cycle of infection and recurrence underscores the need for novel approaches to the treatment and prevention of C. difficile infections. This review summarizes previous and ongoing efforts to develop active and passive immunization strategies for the prevention of primary and recurrent C. difficile infections.