Isolation of Toxigenic Clostridium difficile from Animal Manure and Composts Being Used as Biological Soil Amendments.

The well-known nosocomial pathogen has recently been recognized as a community-associated pathogen. As livestock animals carry and shed in their feces, animal manure-based composts may play an important role in disseminating toxigenic strains into the agricultural environment. The present study surveyed contamination of commercially available composts and animal manure. Presumptive isolates were confirmed by testing for the housekeeping gene in addition to Gram staining. The confirmed isolates were further tested for toxigenicity, PCR ribotype, and susceptibilities to selected antibiotics. was found in 51 out of 142 samples (36%). A total of 58 strains were isolated from those 51 positive compost/manure samples. The presence of in compost did not significantly correlate ( > 0.05) with the physical and most microbiological parameters, including the presence of fecal coliforms. The majority of isolates were toxigenic, with 63.8% positive for the toxin A gene () and 67.2% positive for the toxin B gene (). Only 3 isolates (5.17%) were positive for the binary toxins. There were 38 different PCR ribotypes among the 58 isolates, and ribotype 106 was the most prevalent, followed by ribotypes 020 and 412. All isolates were susceptible to the selected antibiotics, but >50% of the isolates had reduced susceptibility to clindamycin by the agar dilution method. This study indicates that compost may be a reservoir of toxigenic strains. infection (CDI) is a leading cause of antibiotic-associated diarrhea in health care facilities in developed countries. Extended hospital stays and recurrences severely increase the cost of treatments and the high mortality rate that is observed among the elderly. Community-associated CDI cases that occur without any recent contact with the hospital environment are increasing. Studies have reported the isolation of virulent strains from water, soil, meat, vegetables, pets, livestock animals, and animal manure. The objective of this study was to isolate and characterize strains from animal manure and commercially available compost products. Our results demonstrate that not only unprocessed animal manure but also finished composts made of different feedstocks can serve as a reservoir for as well. Most importantly, our study revealed that properly processed compost is a potential source of toxigenic and clindamycin-resistant isolates.