Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Food and Food Products of Poultry Origin in Germany

Abstract

ABSTRACTDuring a survey of fresh chicken and turkey meat as well as chicken and turkey meat products for the presence of methicillin-resistantStaphylococcus aureus(MRSA) isolates in Germany, 32 (37.2%) of 86 samples were MRSA positive. Twenty-eight of these MRSA isolates belonged to clonal complex 398 (CC398), which is widespread among food-producing animals. These CC398 isolates carried SCCmecelements of type IV or V and exhibitedspatype t011, t034, t899, t2346 or t6574 and either the knowndrutypes dt2b, dt6j, dt10a, dt10q, dt11a, dt11v, and dt11ab or the noveldrutypes dt6m, dt10as, and dt10at. In addition, two MRSA sequence type 9 (ST9) isolates with a type IV SCCmeccassette,spatype t1430, anddrutype dt10a as well as single MRSA ST5 and ST1791 isolates with a type III SCCmeccassette,spatype t002, anddrutype dt9v were identified. All but two isolates were classified as multiresistant. A wide variety of resistance phenotypes and genotypes were detected. All isolates were negative for the major virulence factors, such as Panton-Valentine leukocidin, toxic shock syndrome toxin 1, or exfoliative toxins. In contrast to the MRSA CC398 isolates, the four ST9, ST5, or ST1791 isolates harbored theegcgene cluster for enterotoxin G, I, M, N, O, and U genes. Although the relevance of contamination of fresh poultry meat or poultry products with MRSA is currently unclear, the presence of multiresistant and, in part, enterotoxigenic MRSA emphasizes the need for further studies to elucidate possible health hazards for consumers.