The aim of this study was to evaluate the prevalence and molecular characteristics of methicillinresistant Staphylococcus aureus (MRSA) among pigs and estimate the impact of this animal reservoir on human healthcare. Nasal swabs were derived from 1,600 pigs at 40 German farms. The MRSA were characterized using S. aureus protein A (spa) typing, multilocus sequence typing (MLST) and detection of toxin genes. In a retrospective case control study, we compared risk factors for the carriage of MRSA between patients carrying spa types found among regional pigs and patients with other MRSA molecular types. Pigs carrying MRSA were identified on 70% of the farms (spa types t011, t034, t108, t1451 and t2510, all associated with MLST sequence type ST398). Contact to pigs and cattle were independent risk factors for the carriage of these spa types in patients at hospital admission. Our results indicate that livestock represents a relevant reservoir for the import of MRSA into regional German hospitals.

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dLivestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is frequently transmitted from pigs to farmers. This study analyzed whether an absence from direct contact with pigs during holidays had an impact on nasal MRSA colonization rates of pig farmers. Overall, 59% of the farmers did not clear MRSA colonization during their leave.

dClostridium difficile was isolated from 147 of 201 (73%) rectal swabs of piglets from 15 farms of Lower Saxony and North Rhine-Westphalia. In 14 farms, 14 to 100% (mean, 78%) of the animals tested were culture positive. The rate of isolation was 68% postpartum, increased to 94% in animals 2 to 14 days of age, and declined to 0% for animals 49 days of age and older. There was no link between isolation and antibiotic treatment or diarrhea of piglets. Strains were assigned to 10 PCR ribotypes, and up to 4 PCR ribotypes were found to be present at the same time on a farm. The closely related PCR ribotypes 078 (55%) and 126 (20%) were most frequently recovered and were present in 13 of the 14 positive farms. The comparison of multilocus VNTR (variable number of tandem repeats) analysis (MLVA) data from this study and previously published data on human, porcine, and bovine PCR ribotype 078 isolates from 5 European countries revealed genetic differences between strains of different geographic origin and confirmed the relatedness of human and porcine C. difficile isolates. This study demonstrated that the human-pathogenic PCR ribotypes 078 and 126 are predominant in piglets in Germany. The results suggest that presence of C. difficile is correlated with animal age but not with antibiotic treatment or clinical disease. MLVA indicated that strains of the same geographical origin are often genetically related and corroborated the hypothesis of a close epidemiological connection between human and porcine C. difficile isolates.

g Colonization of livestock with bacteria resistant to antibiotics is considered a risk for the entry of drug-resistant pathogens into the food chain. For this reason, there is a need for novel concepts to address the eradication of drug-resistant commensals on farms. In the present report, we evaluated the decontamination measures taken on a farm contaminated with methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae expressing extended-spectrum ␤-lactamases (ESBL-E). The decontamination process preceded the conversion from piglet breeding to gilt production. Microbiological surveillance showed that the decontamination measures eliminated the MRSA and ESBL-E strains that were detected on the farm before the complete removal of pigs, cleaning and disinfection of the stable, and construction of an additional stable meeting high-quality standards. After pig production was restarted, ESBL-E remained undetectable over 12 months, but MRSA was recovered from pigs and the environment within the first 2 days. However, spa (Staphylococcus aureus protein A gene) typing revealed acquisition of an MRSA strain (type t034) that had not been detected before decontamination. Interestingly, we observed that a farmworker who had been colonized with the prior MRSA strain (t2011) acquired the new strain (t034) after 2 months. In summary, this report demonstrates that decontamination protocols similar to those used here can lead to successful elimination of contaminating MRSA and ESBL-E in pigs and the stable environment. Nevertheless, decontamination protocols do not prevent the acquisition of new MRSA strains. N umerous studies have highlighted the emergence of methicillin-resistant Staphylococcus aureus (MRSA) (1-4) and Enterobacteriaceae expressing extended-spectrum ␤-lactamases (ESBL-E) (5-7) in livestock production, particularly in pigs. Hence, there is an ongoing debate whether the use of antibiotics in food animal production represents an important source of continuous spread of MRSA and ESBL-E to humans (8-10). Farmers are confronted with two different consequences of this problem: the potential danger of animal colonization with drug-resistant bacteria for (i) humans living on or in the vicinity of farms (11-13) and for (ii) consumers of animal products (14-18). Indeed, livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have been found in humans living and working in close contact with pigs and also in hospitals in rural areas (11,(19)(20)(21)(22)(23)(24)(25). In contrast, ESBL-E could possibly be transferred from animals to humans via meat products (16,(26)(27)(28). As a consequence, control points to limit transmission of resistant pathogens "from stable to table" have been demanded (29).Notably, bacteria not only persist on/in the living animal but also on surfaces that are in contact with the animals, such as barn walls and equipment (30, 31). LA-MRSA isolates were detected in dust samples from the investigated breeding farms in Germany as part of the EFSA (European Food Safe...