Participating researchers and public health personnel at a Canadian workshop in 2007, noted considerable gaps in current understanding of community-associated Clostridium difficile infection (CA-CDI), specifically infection sources and risk factors. A disease transmission model for CA-CDI was requested as an initial step towards a risk assessment, to analyse infection sources and risk factors, addressing priority research areas. The developed model contains eight infection states (susceptible, gastrointestinal exposure, colonized, diseased, deceased, clinically resolved colonized, relapse diseased, and cleared) and notes directional transfers between the states. Most published research used focused on hospital-associated C. difficile infection (HA-CDI) and further studies are needed to substantiate the use of HA-CDI knowledge in the transmission of CA-CDI. The aim was to provide a consistent framework for researchers, and provide a theoretical basis for future quantitative risk assessment of CA-CDI.
(Accepted December 08 2009)
(Online publication January 22 2010)
c1 Author for correspondence: Mrs A. M. Otten, Laboratory for Foodborne Zoonoses, Public Health Agency of Canada, 110 Stone Road West, Guelph, ON, N1G 3W4, Canada. (Email: Ainsley.Otten@phac-aspc.gc.ca)