Prevalence and molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) among pigs on German farms and import of livestock-related MRSA into hospitals

Abstract

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.

Epidemiological Aspects of Oxacillin-Resistant Staphylococcus spp.: The Use of Molecular Tools with Emphasis on MLST

“…Smith et al (2009) reported the presence of ST398 samples in swines and farmers in the mid-western region of the United States, which suggests transmission between animals and their breeders. In Germany, 1,600 swabs from swines from 40 farms were analyzed in a study where samples typed as ST398 were also identified (Köck et al, 2009).…”

L’histoire de Staphylococcus aureus ST398 : un paradigme médical du 21ème siècle

“…Mais aucun prélèvement n'a été effectué (Wulf et al 2008a). Plus récemment en Allemagne, l'impact du réservoir animal (porc) a été jugé capital (70 % d'éle-vages hébergeant ST398) avec en corollaire, l'éventuelle diffusion de souches, en particulier dans les hôpitaux régionaux (Köck et al 2009 …”

Methicillin-Resistant Staphylococcus aureus (MRSA) in Food- Producing and Companion Animals and Food Products

“…The acquisition of enterotoxin genes along with the virulence factors, such as Panton-Valentine leukocidin (pvl) genes by LA-MRSA may eventually pose a threat to humans, suggesting that animals have the potential to be a source of primary contamination as well [16,44]. prevalent strains of S. aureus in pig farmers was CC398 [45][46][47][48][49]. Forty-ive percent of veterinarians atending pig farms in the Netherlands were positive for MRSA [48].…”

“…In Belgium and Denmark, the prevalence of MRSA in veterinarians was 9.5% and 1.4%, respectively [47]. German researchers reported that MRSA ST398 that carried SCCmec IV or V, accessory gene regulator type I and capsule type 5 [25] in pig primary production herds was higher in their country (45-70%) than in the rest of the European Union [45,46]. In an interesting report, 12.5% of atendees at an international meeting concerning pig health carried MRSA and 91.2% (31/34) of them CC398 [50].…”

“…A recent Dutch study indicated that the annual incidence of MRSA in humans more than tripled from 2001 to 2006 where 23%, 26%, 16%, and 10% of the patients acquired MRSA from a foreign hospital, animals, nosocomial transmission, and the community, respectively [105]. The presence of MRSA CC398 in pig farms with a concomitant increase in CC398 infections in humans clearly suggests that pigs or catle are speciically a risk factor and CC398 MRSA colonization and prevalence in humans is associated with animal contact [23,46,106,107]. The above argument is further strengthened by the indings that the CC398 carrier status of farm workers decreased dramatically when they took a break from direct animal care duties [19,100].…”