Cross sectional study on the prevalence of Clostridium difficile in pig farmers, their family members and the pigs on the farm; an indication for interspecies transmission?

Abstract

Identical Clostridium difficile ribotype 078 isolates were cultured from piglets with diarrhea and from humans with CDI. This led to the hypothesis that interspecies transmission could occur. The aim of this study was to investigate whether people who have occupational contact with pigs, and their family members, have higher colonization rates with C. difficile and to determine if similar C. difficile ribotypes could be found in farmers, employees, family members, and pigs on the same farm. Therefore, fecal samples from pig famers and their employees, family members and pigs on the same farms were analyzed for the presence of C. difficile. In total 125 of the 400 pig samples were found positive for Clostridium difficile. Ribotype 078 was the most common ribotype, found in fecal samples from pigs at 37 of the 40 farms. Beside this ribotype also type 001, 126, 045 and an unknown ribotype were found in the pigs. At 16 farms humans were found positive for the bacterium. At all these farms corresponding ribotypes were found in the humans and the pigs. At 15 farms type 078 was predominant in the pigs and found in the humans, and at 1 farm only type 045 was found in the pigs and the humans. In total 13 (24%) farmers and employees, and 5 (16%) partners carried Clostridium difficile in their feces. All the partners that were positive for the bacterium reported a regular contact with the pigs. None of the children was positive for the bacterium. The results of this study indicate that occupational contact with pigs may lead to a higher risk of colonization with C. difficile, since higher colonization rates in people in direct contact with pigs, then in the general population were found.