Franziska Layer

Robert Koch Institut, Berlín, Berlin, Germany

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Publications (29)99.21 Total impact

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    ABSTRACT: Co-trimoxazole (trimethoprim/sulfamethoxazole) is clinically valuable in treating skin and soft tissue infections (SSTIs) caused by community-associated methicillin-resistant Staphylococcus aureus (MRSA). The genetic basis of emerging trimethoprim/sulfamethoxazole resistance in S. aureus from Africa is unknown. Such knowledge is essential to anticipate its further spread. We investigated the molecular epidemiology of trimethoprim resistance in S. aureus collected in and imported from Africa.
    Journal of Antimicrobial Chemotherapy 05/2014; · 5.34 Impact Factor
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    ABSTRACT: MALDI-TOF mass spectrometry (MALDI-TOF MS) is increasingly used as a reliable technique for species identification of bacterial pathogens. In this study we investigated the question of whether MALDI-TOF MS can be used for accurate sub-differentiation of strains and isolates of two important nosocomial pathogens Enterococcus faecium and Staphylococcus aureus. For this purpose, a selection of 112 pre-characterized E. faecium isolates (clonal complexes CC2, CC5, CC9, CC17, CC22, CC25, CC26, CC92 altogether 52 multilocus sequence types) and 59 diverse S. aureus isolates (mostly methicillin resistant; CC5, CC8, CC22, CC30, CC45, CC398) were studied using a combination of MALDI-TOF MS and advanced methods of spectral data analysis. The strategy of MS data evaluation included manual peak inspection on the basis of pseudo gel views, unsupervised hierarchical cluster analysis and supervised artificial neural network (ANN) analysis. We were capable of differentiating patterns of hospital-associated E. faecium isolates (CC17) from other strains of E. faecium with 87% accuracy, but failed to identify lineage-specific biomarker peaks. For S. aureus pattern analyses we were able to confirm a number of signals described in previous studies, but often failed to identify biomarkers that would allow a consistent and reliable identification of phylogenetic lineages, clonal complexes or sequence types. Hence, the discriminatory power of MALDI-TOF MS was found to be insufficient for reliably sub-differentiating E. faecium and S. aureus isolates to the level of distinct clones or clonal complexes, such as assessed by MLST. Further, a comparison between peak patterns of susceptible and resistant isolates did not identify statistically relevant marker peaks linked to glycopeptide resistance determinants (vanA, vanB) in E. faecium, or the methicillin resistance determinant (mecA) in S. aureus.
    Journal of microbiological methods 03/2014; · 2.43 Impact Factor
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    ABSTRACT: Frequency, persistence and molecular characteristics of multidrug resistant bacteria colonizing inhabitants of long term care facilities are topics of current concern. We performed a point-prevalence survey of 402 residents in 7 elderly care facilities in Berlin, Germany. Inguinal swabs were analyzed for the presence of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), and multidrug-resistant gram-negative bacteria. Three and six months following the initial investigation, all colonized residents were sampled again and the occurrence of intercurrent infections, hospital admissions and use of antimicrobials were registered. Genetic relatedness of the bacteria was investigated using multi-locus sequence typing (MLST), spa-typing and SmaI/XbaI-macrorestriction analysis. 33 (8.2%) residents were skin-colonized with multidrug-resistant bacteria. MRSA were found in 19 (4.7%) and ESBL-producing Enterobacteriaceae in 16 residents (3.98%). Independent risk factors for colonization with multidrug-resistant bacteria were a high level of care and the presence of chronic wounds. A large proportion of the observed bacteria persisted up to six months and showed a high degree of inter-individual diversity. Outcome analysis revealed that infections tend to occur slightly more often in residents colonized by multiresistant pathogens. We assume that a perceptible population of residents in nursing homes is at risk for individual colonization with multidrug-resistant bacteria as well as healthcare associated infections.
    International Journal of Medical Microbiology. 01/2014;
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    ABSTRACT: The findings from truly randomized community-based studies on Staphylococcus aureus nasal colonization are scarce. Therefore we have examined point prevalence and risk factors of S. aureus nasal carriage in a non-hospitalized population of Braunschweig, northern Germany.
    PLoS ONE 01/2014; 9(9):e107937. · 3.53 Impact Factor
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    ABSTRACT: In the early 2000s, a particular MRSA clonal complex (CC398) was found mainly in pigs and pig farmers in Europe. Since then, CC398 has been detected among a wide variety of animal species worldwide. We investigated the population structure of CC398 through mutation discovery at 97 genetic housekeeping loci, which are distributed along the CC398 chromosome within 195 CC398 isolates, collected from various countries and host species, including humans. Most of the isolates in this collection were received from collaborating microbiologists, who had preserved them over years. We discovered 96 bi-allelic polymorphisms, and phylogenetic analyses revealed that an epidemic sub-clone within CC398 (dubbed 'clade (C)') has spread within and between equine hospitals, where it causes nosocomial infections in horses and colonises the personnel. While clade (C) was strongly associated with S. aureus from horses in veterinary-care settings (p = 2×10(-7)), it remained extremely rare among S. aureus isolates from human infections.
    PLoS ONE 01/2014; 9(2):e88083. · 3.53 Impact Factor
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    ABSTRACT: In April 2013, a food poisoning outbreak caused by staphylococcal enterotoxins (SE) in ice-cream occurred in Freiburg, Germany, among the 31 participants of a christening party. Of the 13 cases, seven were hospitalized or obtained ambulatory treatment. Different types of ice-cream which was freshly produced at the hotel where the party took place, was found to contain SE and high amounts of coagulase positive staphylococci. Enterotoxigenic Staphylococcus aureus strains isolated from ice-cream and human cases were of the same spa-type (t127), harboured the sea gene and displayed identical phenotypic resistance-, Fourier transform infrared spectroscopy- (FT-IR) and microarray-profiles. Despite the strong microbiological and epidemiological evidence of ice-cream being the incriminated food vehicle of the outbreak, a common source of S. aureus from the ice-cream could not be deduced. As none of the employees carried the outbreak strain, either the equipment used for the production of the ice-cream or a contaminated ingredient are the most likely introduction source.
    International Journal of Food Microbiology. 01/2014;
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    ABSTRACT: To elucidate the evolutionary history of Staphylococcus aureus clonal complex (CC) 8, which encompasses several globally distributed epidemic lineages, including hospital-associated methicillin-resistant S. aureus (MRSA) and the highly prevalent community-associated MRSA clone USA300. We reconstructed the phylogeny of S. aureus CC8 by mutation discovery at 112 genetic housekeeping loci from each of 174 isolates, sampled on five continents between 1957 and 2008. The distribution of antimicrobial resistance traits and of diverse mobile genetic elements was investigated in relation to the isolates' phylogeny. Our analyses revealed the existence of nine phylogenetic clades within CC8. We identified at least eight independent events of methicillin resistance acquisition in CC8 and dated the origin of a methicillin-resistant progenitor of the notorious USA300 clone to the mid-1970s. Of the S. aureus isolates in our collection, 88% carried plasmidic rep gene sequences, with up to five different rep genes in individual isolates and a total of eight rep families. Mapping the plasmid content onto the isolates' phylogeny illustrated the stable carriage over decades of some plasmids and the more volatile nature of others. Strikingly, we observed trends of increasing antibiotic resistance during the evolution of several lineages, including USA300. We propose a model for the evolution of S. aureus CC8, involving a split into at least nine phylogenetic lineages and a subsequent series of acquisitions and losses of mobile genetic elements that carry diverse virulence and antimicrobial resistance traits. The evolution of MRSA USA300 towards resistance to additional antibiotic classes is of major concern.
    Journal of Antimicrobial Chemotherapy 10/2013; · 5.34 Impact Factor
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    ABSTRACT: The widespread use of antibiotics in association with high-density clinical care has driven the emergence of drug-resistant bacteria that are adapted to thrive in hospitalised patients. Of particular concern are globally disseminated methicillin-resistant Staphylococcus aureus (MRSA) clones that cause outbreaks and epidemics associated with healthcare. The most rapidly spreading and tenacious healthcare-associated clone in Europe currently is EMRSA-15, a lineage that was first detected in the UK in the early 1990s and subsequently spread throughout Europe and beyond. To understand the genetic events that have accompanied the emergence of the EMRSA-15 pandemic, we obtained genome sequences for 193 isolates that were chosen for their geographical and temporal diversity, and belong to the same multilocus sequence type as EMRSA-15. Using phylogenomic methods, we were able to show that the current pandemic population of EMRSA-15 descends from a healthcare-associated MRSA epidemic that spread through England in the 1980s, which had itself previously emerged from a primarily community-associated methicillin-sensitive population. The emergence of fluoroquinolone resistance in this EMRSA-15 sub-clone in the English Midlands during the mid-1980s appears to have played a key role in triggering pandemic spread, and occurred shortly after the first clinical trials of this drug. Genome-based coalescence analysis estimated that the population of this sub-clone over the last twenty years has grown four times faster than its progenitor. Using comparative genomic analysis we were able to identify the molecular genetic basis of 99.8% of the antimicrobial resistance phenotypes of the isolates, highlighting the potential of pathogen genome sequencing as a diagnostic tool. We document the genetic changes associated with adaptation to the hospital environment and with increasing drug resistance over time, and how MRSA evolution likely has been influenced by country-specific drug use regimens.
    Genome Research 01/2013; · 14.40 Impact Factor
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) may cause prolonged outbreaks of infections in neonatal intensive care units (NICUs). While the specific factors favouring MRSA spread on neonatal wards are not well understood, colonized infants, their relatives, or health-care workers may all be sources for MRSA transmission. Whole-genome sequencing may provide a new tool for elucidating transmission pathways of MRSA at a local scale. We applied whole-genome sequencing to trace MRSA spread in a NICU and performed a case-control study to identify risk factors for MRSA transmission. MRSA genomes had accumulated sequence variation sufficiently fast to reflect epidemiological linkage among individual patients, between infants and their mothers, and between infants and staff members, such that the relevance of individual nurses' nasal MRSA colonization for prolonged transmission could be evaluated. In addition to confirming previously reported risk factors, we identified an increased risk of transmission from infants with as yet unknown MRSA colonisation, in contrast to known MRSA-positive infants. The integration of epidemiological (temporal, spatial) and genomic data enabled the phylogenetic testing of several hypotheses on specific MRSA transmission routes within a neonatal intensive-care unit. The pronounced risk of transmission emanating from undetected MRSA carriers suggested that increasing the frequency or speed of microbiological diagnostics could help to reduce transmission of MRSA.
    PLoS ONE 01/2013; 8(1):e54898. · 3.53 Impact Factor
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    ABSTRACT: We investigated the population structure of Staphylococcus aureus clonal complex CC121 by mutation discovery at 115 genetic housekeeping loci from each of 154 isolates, sampled on five continents between 1953 and 2009. In addition, we pyro-sequenced the genomes from ten representative isolates. The genome-wide SNPs that were ascertained revealed the evolutionary history of CC121, indicating at least six major clades (A to F) within the clonal complex and dating its most recent common ancestor to the pre-antibiotic era. The toxin gene complement of CC121 isolates was correlated with their SNP-based phylogeny. Moreover, we found a highly significant association of clinical phenotypes with phylogenetic affiliations, which is unusual for S. aureus. All isolates evidently sampled from superficial infections (including staphylococcal scalded skin syndrome, bullous impetigo, exfoliative dermatitis, conjunctivitis) clustered in clade F, which included the European epidemic fusidic-acid resistant impetigo clone (EEFIC). In comparison, isolates from deep-seated infections (abscess, furuncle, pyomyositis, necrotizing pneumonia) were disseminated in several clades, but not in clade F. Our results demonstrate that phylogenetic lineages with distinct clinical properties exist within an S. aureus clonal complex, and that SNPs serve as powerful discriminatory markers, able to identify these lineages. All CC121 genomes harboured a 41-kilobase prophage that was dissimilar to S. aureus phages sequenced previously. Community-associated MRSA and MSSA from Cambodia were extremely closely related, suggesting this MRSA arose in the region.
    PLoS ONE 01/2013; 8(3):e58155. · 3.53 Impact Factor
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    ABSTRACT: Methicillin-susceptible Staphylococcus aureus (MSSA) attributed to clonal complex (CC) 398 and exhibiting spa-type t571 received attention in Europe and in the USA for being associated with severe infections in humans. As this spa-type is exhibited by livestock-associated (LA) Methicillin-resistant S. aureus (MRSA) as well, it is important to discriminate LA- and human-derived strains by easy to perform, PCR-based methods. MSSA t571 contain phage int3 carrying scn and chp, whereas LA-MRSA t571 lack these markers. In contrast, pathogenicity island SaPIbov5 (detected by PCR bridging vwbbov and scn) is contained by LA-MRSA t571 and absent in the human MSSA subpopulation. Furthermore, MSSA t571 contain erm(T), the particular genomic arrangement of which was assessed by a PCR bridging erm(T) and the adjacent transposase gene. MSSA t571 are rare so far in Germany among isolates from infections in humans (0.14%) as well as among isolates from nasal colonization (0.13%). LA-MRSA t571 are also infrequent among MRSA isolated from carriage at admission to hospitals (0.1%) and also among isolates from infections in humans (0.013%).
    PLoS ONE 01/2013; 8(12):e83165. · 3.53 Impact Factor
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    ABSTRACT: Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are a problem in hospital settings worldwide. The National Reference Centre for Staphylococci performs molecular typing on a representative sample set of MRSA isolates from German hospitals for assessing long-term trends thus following the dynamics of emergence and spread of MRSA clones. The article focuses on recent data concerning antibiotic resistance and epidemic MRSA in nosocomial settings and also reflects the impact of community-acquired MRSA and MRSA from zoonotic reservoirs. Identifying common and newly emerging clones is an on-going challenge in the changing epidemiology of MRSA and prevention of further spread needs molecular surveillance.
    Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz 11/2012; 55(11-12):1377-86. · 0.72 Impact Factor
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    ABSTRACT: We developed, tested, and applied a TaqMan real-time PCR assay for interrogation of three single-nucleotide polymorphisms that differentiate a clade (termed 't003-X') within the radiation of methicillin-resistant Staphylococcus aureus (MRSA) ST225. The TaqMan assay achieved 98% typeability and results were fully concordant with DNA sequencing. By applying this assay to 305 ST225 isolates from an international collection, we demonstrate that clade t003-X is endemic in a single acute-care hospital in Germany at least since 2006, where it has caused a substantial proportion of infections. The strain was also detected in another hospital located 16 kilometers away. Strikingly, however, clade t003-X was not found in 62 other hospitals throughout Germany nor among isolates from other countries, and, hence, displayed a very restricted geographical distribution. Consequently, our results show that SNP-typing may be useful to identify and track MRSA clones that are specific to individual healthcare institutions. In contrast, the spatial dissemination pattern observed here had not been resolved by other typing procedures, including multilocus sequence typing (MLST), spa typing, DNA macrorestriction, and multilocus variable-number tandem repeat analysis (MLVA).
    PLoS ONE 01/2012; 7(3):e32698. · 3.53 Impact Factor
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    ABSTRACT: Tracing the spatial spread of pathogens is a key objective of molecular infectious disease epidemiology. Accordingly, a wide range of genotyping approaches have been used to monitor the dissemination of Staphylococcus aureus strains, from localized outbreaks to global spread. We provide a critical review of available methods, revealing that molecular markers currently in use for typing S. aureus acquire changes so slowly that they monitor evolutionary change over timescales that are largely irrelevant to epidemiology. Moreover, the more variable markers frequently do not reflect the pathogen's evolutionary history and, hence, provide potentially misleading information about spread. More recent work has demonstrated that staphylococcal evolution proceeds sufficiently fast that the dynamics of S. aureus spatial spread can be elucidated at great detail on the basis of genome-wide single-nucleotide polymorphisms.
    International journal of medical microbiology: IJMM 12/2011; 301(8):614-8. · 4.54 Impact Factor
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    Sophia Johler, Franziska Layer, Roger Stephan
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    ABSTRACT: Staphylococcus aureus is the etiological agent in a variety of infections in humans and livestock and produces enterotoxins leading to staphylococcal food poisoning (SFP), one of the most prevalent foodborne intoxication diseases worldwide. Pork and bovine milk are considered possible sources of SFP because pig skin is often colonized by S. aureus and bovine mastitis caused by S. aureus is common, but conclusive data are limited. The objective of the present study was to compare S. aureus isolates associated with cases of SFP with isolates obtained from bovine mastitis milk and pig carcasses. DNA microarray analysis and spa gene typing were performed with 100 S. aureus isolates: 20 isolates related to outbreaks of SFP in humans, 39 isolates obtained from pig carcasses, and 41 isolates collected from bovine mastitis milk. No overlap in spa types was observed for SFP isolates (t008, t015, t018, t024, t056, t084, t279, t377, t383, t648, t733, t912, t1239, t1270, t4802, and t6969) and isolates gathered from milk or pork. The porcine isolates were assigned to t034, t208, t337, t524, t899, t1939, t2922, t2971, t4475, and t7006, and the bovine isolates belonged to t267, t524, t529, t1403, t2953, t7007, t7008, and t7013. Comparison of microarray profiles revealed similar virulence gene patterns for isolates collected from the same host (pigs or cattle) but few similarities between SFP isolate profiles and the profiles of isolates obtained from bovine mastitis milk and pig carcasses. Although only some bovine and porcine isolates possessed the β-lactamase gene blaZ (milk, 24%; pork, 28%), significantly higher numbers of SFP isolates contained blaZ (90%). Investigations of these isolates provided no evidence that pork or bovine mastitis milk represent common sources of SFP.
    Journal of food protection 11/2011; 74(11):1852-9. · 1.83 Impact Factor
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    ABSTRACT: Staphylococcus aureus represents an organism of striking versatility. While asymptomatic nasal colonization is widespread, it can also cause serious infections, toxinoses and life-threatening illnesses in humans and animals. Staphylococcal food poisoning (SFP), one of the most prevalent causes of foodborne intoxication worldwide, results from oral intake of staphylococcal enterotoxins leading to violent vomiting, diarrhea and cramps shortly upon ingestion. The aim of the present study was to compare isolates associated with SFP to isolates collected from cases of human nasal colonization and clinical infections in order to investigate the role of S. aureus colonizing and infecting humans as a possible source of SFP. Spa typing and DNA microarray profiling were used to characterize a total of 120 isolates, comprising 50 isolates collected from the anterior nares of healthy donors, 50 isolates obtained from cases of clinical infections in humans and 20 isolates related to outbreaks of staphylococcal food poisoning. Several common spa types were found among isolates of all three sources (t015, t018, t056, t084). DNA microarray results showed highly similar virulence gene profiles for isolates from all tested sources. These results suggest contamination of foodstuff with S. aureus colonizing and infecting food handlers to represent a source of SFP.
    European Journal of Clinical Microbiology 07/2011; 31(4):455-64. · 3.02 Impact Factor
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    ABSTRACT: Staphylococcus aureus is an important pathogen causing a wide range of infections in the hospital and community setting. In order to have adequate information for treatment of S. aureus infections, it is crucial to understand the trends in the antibiotic-resistance patterns. In addition, the occurrence and changes in types of S. aureus, clonal identities, and their geographic spread is essential for the establishment of adequate infection control programmes. In this study, 68 S. aureus isolates obtained from clinical and non-clinical sources in Nigeria between January and April 2009 were characterized using phenotypic and molecular methods. All the S. aureus isolates were susceptible to teicoplanin, vancomycin, phosphomycin, fusidic acid, rifampicin, daptomycin, mupirocin, linezolid and tigecycline. Sixteen percent of the isolates were resistant to oxacillin, while 55% and 72% of isolates were resistant to tetracycline and trimethoprim/sulphamethoxazole (cotrimoxazole), respectively (Table 1). There was excellent correlation between the broth microdilution assay and detection of antibiotic resistance genes by the multiplex PCR, in the determination of S. aureus resistance to erythromycin, gentamicin, methicillin and tetracycline. A total of 28 spa types were identified in the study, and the predominant spa type among the methicillin-susceptible S. aureus (MSSA) isolates was t084 (13 isolates). The t037-ST241-SCCmecIII type was the only clone identified in Maiduguri (North-East Nigeria) while in South-West Nigeria, diversity among the MRSA isolates (t451-ST8-SCCmecV; t008-ST94-SCCmecIV; t002-ST5-SCCmecV; t064-ST8-SCCmecV) was observed. The toxin genes seh and etd were detected in isolates affiliated with clonal complexes CC1, CC80 and sequence type ST25, respectively. The proportion of PVL-positive isolates among MSSA was high (40%). Most of the PVL-positive MSSA isolates were obtained from wound infections and associated with clonal complexes CC1, CC30, CC121 and with sequence type ST152. The use of phenotypic and molecular methods provided useful information on antibiotic resistance and molecular diversity of S. aureus in Nigeria. The high proportion of PVL-positive MSSA isolates affiliated to various clonal complexes and detected in all the health institutions is a major concern, both as a source of severe infections and as a potential reservoir that could lead to the emergence of PVL-positive MRSA. This study presents the first baseline information on the nature of the antibiotic resistance genes from S. aureus isolates in Nigeria. There is the need to curtail the spread and establishment of MRSA and PVL-positive MSSA clones in Nigerian health care institutions.
    BMC Microbiology 01/2011; 11:92. · 2.98 Impact Factor
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    ABSTRACT: MRSA CC130 containing the mecA homologue mecA(LGA251) were reported from the UK and from Denmark so far from cattle and humans. Here we report on 11 MRSA CC130 among a sample of 12691 isolates of human origin collected from January 2006 until June 2011. MRSA CC130 grew insufficiently on chromogernic agar plates for detection of MRSA; the agglutination test for presence of PBP2a was negative. We designed primers for specific detection of mecA(LGA251) as well as for concomitant detection of both, mec(LGA251) and mecA. As already described, the isolates exhibited spa-types t843, t1736, and t1773. The ccrA homologue indicated the presence SCCmec(XI). When subjected to further characterization by means of a commercially available microarray the isolates were negative for sak chp, and scn, and as expected positive for hla, untruncated hlb, and hld. They furthermore contained edinB, aur, slpA, slpB, slpE. From genes coding for surface and cell wall associated products the ica-operon, cap8, clfA, clfF, ebpS, fnbA, fnbB, sdrC were detected but not cna. The isolates were negative for enterotoxin genes and tst, as well as for eta, and etb; agr-type was III.
    PLoS ONE 01/2011; 6(9):e24360. · 3.53 Impact Factor
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    ABSTRACT: The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in animals such as horses, pet animals and productive livestock has raised questions of a probable human origin and in more general of host specificity of S. aureus. Particular clonal lineages are obviously specific for humans (e.g. ST15, ST25, ST45) and other for ruminants (e.g. ST151). MRSA associated with veterinary nosocomial infections (e.g. ST8 and ST254 in horses, ST22 in small animals) very likely have their origin in health care facilities. MRSA ST398 which became first known from widespread colonization in industrially raised pigs seems to have a limited host specificity and is able to colonize and to cause infections in various hosts. Mechanisms of host adaptation and their genomic background are poorly understood so far.
    International journal of medical microbiology: IJMM 12/2009; 300(2-3):109-17. · 4.54 Impact Factor
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    ABSTRACT: Phenotypic, genotypic, and toxin gene analyses have not yet been done all in one for the Nigerian Staphylococcus aureus population. This study provides a comprehensive overview of the molecular epidemiology and genetic diversity of S. aureus strains at the largest university clinic in Ibadan, Nigeria. From 1,300 patients' clinical samples collected at the University Teaching Hospital in Ibadan, Nigeria, during a 1-year-surveillance in 2007, 346 nonduplicate S. aureus isolates were obtained. All isolates underwent antibiotic susceptibility testing, toxin gene analysis, multilocus sequence typing, agr group typing, and spa typing. For methicillin (meticillin)-resistant S. aureus (MRSA), staphylococcal cassette chromosome mec (SCCmec) typing was also performed. Of the 346 isolates, 20.23% were methicillin resistant. Thirty-three patients' isolates (47.15%) fulfilled the definition criteria for community-associated MRSA (CA-MRSA) according to a review of the medical charts. The majority of MRSA strains analyzed were isolated from surgical or pediatric patients. The commonest types of MRSA infection identified were surgical-site infections (>70%), whereas those for CA-MRSA were conjunctivitis and otitis (19 patients [57.6%]) and accidental skin and subcutaneous tissue infections (14 patients [42.4%]). The methicillin-susceptible S. aureus strains (ST1, ST5, ST15, ST7, ST8, ST25, ST30, ST72, ST80, ST121, and ST508) were heterogeneous by phenotypic and genotypic analyses. The first report of a Panton-Valentine leukocidin-positive ST88 strain (agr III, SCCmec IV) in Nigeria, as well as genetic analyses of this strain, is presented in this study. The ST88 strain was resistant to trimethoprim-sulfamethoxazole as well as to penicillin and oxacillin. CA-MRSA infections are increasing rapidly among young patients with ophthalmologic and auricular infections. Urban regions with populations of lower socioeconomic status and evidence of overcrowding appear to be at high risk for the emergence of this clone.
    Journal of clinical microbiology 08/2009; 47(9):2975-80. · 4.16 Impact Factor

Publication Stats

530 Citations
99.21 Total Impact Points

Institutions

  • 2009–2014
    • Robert Koch Institut
      • Department for Infectious Disease Epidemiology
      Berlín, Berlin, Germany
    • University College Hospital Ibadan
      Ibadan, Oyo, Nigeria
  • 2013
    • Wellcome Trust Sanger Institute
      Cambridge, England, United Kingdom
  • 2011
    • Obafemi Awolowo University
      • Department of Microbiology
      Ilesa, Osun State, Nigeria
  • 2006–2008
    • Otto-von-Guericke-Universität Magdeburg
      • Institute for Medical Microbiology
      Magdeburg, Saxony-Anhalt, Germany