Raman scattering quantitative assessment of the anion composition ratio in Zn(O,S) layers for Cd-free chalcogenide-based solar cells

This work reports the use of Raman scattering for the chemical characterization of Zn(O,S) layers that are being developed as a Cd-free alternative for the buffer layer in advanced chalcogenide solar cells.

State-wide surveillance of antibiotic resistance patterns and spa types of methicillin-resistant Staphylococcus aureus from blood cultures in North Rhine-Westphalia, 2011-2013

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of bacteraemia. We aimed to obtain a complete picture of severe MRSA infections by characterizing all MRSA isolates from bloodstream infections in the largest German federal state (North Rhine-Westphalia, 18 million inhabitants) using S. aureus protein A (spa) sequence-typing and antimicrobial susceptibility testing. MRSA isolates (n = 1952) were collected prospectively (2011-2013) and spa-typed. Among 181 different spa types, t003 (n = 746 isolates; 38.2%) and t032 (n = 594; 30.4%) were predominant. Analysis of the geographical occurrence of spa clonal complexes (spa-CCs) and spa types revealed divergent distribution between federal state districts for spa-CCs 003 (p < 0.001; including t003, p < 0.001 and t264, p < 0.001), 008 (p 0.021), 011 (p 0.002), 032 (p < 0.001; including t022, p 0.014 and t032, p < 0.001) and spa type t2807 (p < 0.001). MICs of antimicrobial substances were tested using broth microdilution. Of all isolates, 96% were resistant to fluoroquinolones, 78% to erythromycin, 70% to clindamycin, 4% to gentamicin, 2% to rifampicin, 0.4% to daptomycin, 0.1% to linezolid and 0% to vancomycin, respectively. Vancomycin MICs of 2 mg/L involved 0.5% of the isolates. In conclusion, the detection of regional molecular clusters added valuable information for epidemiological case tracing and allowed conclusions to be reached on the importance of newly emerging MRSA reservoirs, such as livestock (spa-CC011), for MRSA bacteraemia in some parts of the federal state. Susceptibility testing revealed broad resistance to substances used for oral treatment, but demonstrated that those antibiotics that are mostly applied for treatment of MRSA bacteraemia and important combination partners were highly susceptible.

Systematic literature analysis and review of targeted preventive measures to limit healthcare-associated infections by meticillin-resistant Staphylococcus aureus

Meticillin-resistant Staphylococcus aureus (MRSA) is a major cause of healthcare-associated infections in Europe. Many examples have demonstrated that the spread of MRSA within healthcare settings can be reduced by targeted infection control measures. The aim of this systematic literature analysis and review was to summarise the evidence for the use of bacterial cultures for active surveillance the benefit of rapid screening tests, as well as the use of decolonisation therapies and different types of isolation measures. We included 83 studies published between 2000 and 2012. Although the studies reported good evidence supporting the role of active surveillance followed by decolonisation therapy, the effectiveness of single-room isolation was mostly shown in non-controlled studies, which should inspire further research regarding this issue. Overall, this review highlighted that when planning the implementation of preventive interventions, there is a need to consider the prevalence of MRSA, the incidence of infections, the competing effect of standard control measures (e.g. hand hygiene) and the likelihood of transmission in the respective settings of implementation.

[Vancomycin-resistant enterococci (VRE). Recent results and trends in development of antibiotic resistance]

Enterococci (mainly E. faecalis, E. faecium) are important nosocomial pathogens predominantly affecting older and/or immunocompromised patients. The bacteria possess a broad spectrum of intrinsic and acquired antibiotic resistance properties. Among these, the transferrable glycopeptide resistance of the vanA and vanB genotypes in vancomycin-resistant enterococci (VRE; reservoir: E. faecium) as well as resistance to last resort antibiotics (e.g. linezolid and tigecycline) are of special concern. Enterococci (including VRE) are easily transferred in hospitals; however, colonizations are far more frequent than infections. Resistance frequencies for vancomycin in clinical E. faecium isolates have remained at a relatively constant level of 8-15% (but with local or regional variations) in recent years whereas frequencies for teicoplanin resistance have shown a slight decrease. Glycopeptide resistance trends correlate with a spread of hospital-associated E. faecium strains carrying the vanA and, with rising frequency in recent years, the vanB gene cluster, the latter being associated with teicoplanin susceptibility. This increased occurrence of vanB-positive E. faecium strains may be caused by an increased use of antibiotics selecting enterococci and VRE as well as due to methodological reasons (e.g. reduced EUCAST MIC-breakpoints for glycopeptides; increased use and sensitive performance of chromogenic VRE agars, increased use of molecular diagnostic assays).

High prevalence of extended-spectrum-β-lactamase-producing Enterobacteriaceae in organic and conventional retail chicken meat, Germany

OBJECTIVES

To determine the prevalence of extended-spectrum β-lactamase (ESBL) production in Enterobacteriaceae in retail chicken meat in Germany.

METHODS

A total of 399 chicken meat samples from nine supermarket chains, four organic food stores and one butcher's shop in two geographically distinct regions (Berlin and Greifswald) were screened for ESBL production using selective agar. Phenotypic ESBL isolates were tested for bla(TEM), bla(CTX-M) and bla(SHV) genes using PCR and DNA sequencing. Antibiotic coresistances were determined and strain typing was performed using PCR-based phylogenetic grouping and XbaI-PFGE.

RESULTS

A total of 185 confirmed ESBL isolates were obtained from 175 samples (43.9%) from all tested sources. The majority of isolates were Escherichia coli producing ESBL types SHV-12 (n = 82), CTX-M-1 (n = 77) and TEM-52 (n = 16). No differences could be observed in the prevalence of ESBL producers between organic and conventional samples. 73.0% of the ESBL producers showed coresistance to tetracycline, 35.7% to co-trimoxazole and 7.6% to ciprofloxacin. Strain typing of selected E. coli isolates from Berlin revealed identical macrorestriction patterns for several isolates from samples taken from the same stores.

CONCLUSIONS

This is the first comprehensive study from Germany showing a high prevalence of TEM-, CTX-M- and SHV-type ESBLs in Enterobacteriaceae isolated from retail chicken meat. The high rate of coresistance to different classes of antibiotics in the ESBL producers might reflect the common veterinary usage of these and related substances. There is an urgent need to further evaluate the role of poultry in the transmission of highly resistant ESBL-producing bacteria in humans.

Phenotyping of Staphylococcus aureus reveals a new virulent ST398 lineage

Staphylococcus aureus sequence type (ST)398, which is commonly found as a colonization strain in pig farming, is emerging more frequently as the cause of human infections. In this study, we analysed ST398 of porcine and human origin at the genetic, protein and immunogenic levels. Although genetic analysis of the genes encoding the major virulence factors revealed the presence of the same genes in all strains studied, the results demonstrated spa type crossing alterations in adhesion abilities in addition to a strongly enhanced lysis activity directly linked to impaired clearance attributable to polymorphonuclear leukocytes (PMNs). This change in virulence pattern indicates high heterogenicity in the ST398 pool that is not based on a different genetic make-up, but probably on variations in the genetic regulation systems. These modifications, which are tightly connected to pathogenicity, cannot be detected by conventional diagnostic methods.

[The influenza pandemic 1968-1970: crisis management in separated Germany - "Vodka and Raspberry Tea"]

The Hong Kong Flu in the years 1968-1970 challenged both German health care systems. This article intends to analyse the patterns of reaction to the pandemic. Both German states faced the threat according to their respective ideological orientation. This applied to the two parts of Berlin - West and East - as well. In the GDR the control of influenza was centrally organized. When the pandemic passed away an influenza guiding document ("Führungsdokument") was made obligatory for the fight against the plague. In the FRG hospital treatment maintained predominance while the outpatient sector was administrated by physicians in private practice. In West- Berlin outpatient clinics were declined by the Association of Physicians ("Kassenärztliche Vereinigung"). In 1970 a first concept of surveillance was presented on the level of the state in West Germany. In the years 1968-1970 vaccinations were not common in both German states. The essay is based on the analysis of archival sources, monographs, scientific and newspaper articles.

[Anesthesia and Angelman syndrome]

Angelman syndrome (AS) is a rare neurodevelopmental disorder with an incidence of 1:10,000-1:40,000 caused by deficient genetic imprinting in the chromosomal segment 15q11-q13. Experimental data suggest that the gamma-aminobutyric acid A (GABA(A)) receptor as well as the N-methyl-D-aspartate (NMDA) or α-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA) receptors may be affected by this condition. The first description of the syndrome goes back to 1965 when the British pediatrician Harry Angelman (1915-1996) recognized similar clinical features in three children. Angelman's description of puppet children was changed to happy puppet syndrome 2 years later before this euphemistic denotation was replaced by the concept Angelman syndrome over the years. Angelman syndrome is characterized by ataxia, jerky movements especially hand flapping, a seizure disorder with a characteristic electroencephalogram (EEG), severe learning difficulties, a happy disposition, lack of verbal communication and dysmorphic facial features. Most hospitalizations are caused by epilepsy and the most common indications for surgical procedures are in dental medicine. The first anesthesiology case report to be published dates back to 2001. A total of 13 cases have now been published and in 11 cases the age was registered (mean age 11.6 years, standard deviation 11.7 and 2 outliers aged 27 and 40 years). In this paper, the published case reports are contrasted with 15 cases of anesthesia in 6 patients with AS who underwent surgery during 14 years of routine operations at a Berlin anesthesiology clinic (mean age 15.9 years, standard deviation 4.2 with no outliers). Besides neurosurgical and orthopedic operations most were dental interventions. Summarized, these cases of anesthesia and the results of the published case reports allow the formulation of guidelines for administration of anesthesia in AS cases but do not permit conclusions on which method of anesthesia is the safest for AS patients. For the preoperative consultation and anesthetization, communication with the patients requires the aid of parents or other relatives. Water and reflecting surfaces may be used to gain contact with AS patients. Patients with AS feel pain like any other person although they are frequently smiling and laughing and this has to be considered especially in major surgery (e.g. scoliosis surgery). The most important life-threatening complication is bradycardia due to vagal hypertonia which can lead to asystole with delayed response to atropine. None of the Berlin patients had severe bradycardia but the complication has to be taken into consideration. The use of drugs to ensure complete reversal of neuromuscular relaxation should be avoided because anticholinergic agents could cause bradycardia. The use of sugammadex in cases of AS has not been tested. To avoid elevation of the vagal tone, the indications for laparascopy have to be considered very carefully. There is no evidence that any drug or hypnotic may be more appropriate or advantageous. Balanced anesthesia and total intravenous anesthesia are possible but the duration of drug effect has to be taken into account. If ketamine is used the side-effects of the drug (psychomimetic reactions, muscular rigidity) should be prevented by the consistent administration of propofol, midazolam or thiopental. Usually AS patients are agitated so that regional anesthesia techniques are difficult to administer. If regional anesthesia does have considerable advantages over general anesthesia in a particular case, peripheral regional anesthesia should be preferred, especially because scoliosis is often present. There is no evidence that AS patients cause more intubation problems but because of facial dysmorphia accurate evaluation is needed in advance. This is even more important for older AS patients because the dysmorphia tends to accelerate during the course of life. Although epilepsy is the primary feature of AS, not every EEG alteration indicates the presence of epilepsy. The advantage in using neuromonitoring for measuring the depth of anesthesia is limited. Administration of anticonvulsants must be continued if they were used preoperatively.

Methicillin-resistant Staphylococcus aureus (MRSA): burden of disease and control challenges in Europe

Methicillin-resistant Staphylococcus aureus (MRSA) isa major cause of healthcare- and community-associated infections worldwide. Within the healthcare setting alone, MRSA infections are estimated to affect more than 150,000 patients annually in the European Union (EU), resulting in attributable extra in-hospital costs of EUR 380 million for EU healthcare systems. Pan-European surveillance data on bloodstream infections show marked variability among EU Member States in the proportion of S. aureus that are methicillin-resistant, ranging from less than 1% to more than 50%. In the past five years, the MRSA bacteraemia rates have decreased significantly in 10 EU countries with higher endemic rates of MRSA infections. In addition to healthcare-associated infections, new MRSA strains have recently emerged as community and livestock-associated human pathogens in most EU Member States. The prevention and control of MRSA have therefore been identified as public health priorities in the EU. In this review, we describe the current burden of MRSA infections in healthcare and community settings across Europe and outline the main threats caused by recent changes in the epidemiology of MRSA. Thereby, we aim at identifying unmet needs of surveillance, prevention and control of MRSA in Europe.

[Epidemiology of severe Clostridium difficile infections in Hesse, Germany in 2008-2009]

BACKGROUND AND OBJECTIVE

Clostridium difficile is a major cause of health care associated infections in industrialized countries. During the past decade, the incidence and clinical severity of C. difficile infections (CDI) have increased markedly. This increase has been associated with the emergence of a possibly highly virulent strain, the C. difficile PCR ribotype 027. We investigated the emergence of severe CDI and the associated PCR ribotypes in Hesse, Germany.

PATIENTS AND METHODS

We conducted a retrospective analysis of clinical information and ribotyping results of all cases of severe CDI that were reported to the Hesse State Health Office or sent to our microbiologic diagnostic laboratory for detection and molecular typing of C. difficile in severe cases of CDI from 01/2008 to 12/2009. The data of a of 88 patients and 50 isolates were analysed.

RESULTS

89% of patients were at least 65 years old; the mean age was 77 years. The clinical outcome was known in 85 patients. 27% had died within 30 days of the diagnosis of CDI. Ribotyping results were available in 39 and 11 patients from 2008 and 2009, respectively. The isolates were assigned to nine different ribotypes. RT 027 and RT 001 were the most frequent ribotypes with 31 and 10 isolates, respectively. All other ribotypes were isolated once or twice.

CONCLUSION

Our data indicate that C. difficile RT 027 and RT 001 are prevalent in Hesse and are often associated with severe or notifiable CDI. The high prevalence of RT 027 among the reported CDI cases does not indicate a generally high prevalence of the latter strain in Hesse, because detection of RT 027 was a case definition criterion, a fact that may cause a bias in the reported data. Further investigation would help to improve our understanding of the molecular epidemiology of severe CDI and to improve the prevention strategies.

Nosocomial Staphylococcal scalded skin syndrome caused by intra-articular injection

BACKGROUND

The pathogenic role of nasal carriage as a source for cutaneous and soft-tissue Staphylococcus aureus (SA) infections, and Staphylococcal scalded skin syndrome (SSSS) in particular, is unclear.

OBSERVATION

We herein describe a nosocomial outbreak of SSSS in three orthopaedic patients who received intra-articular injections by a single orthopaedic surgeon. Bacteriological samples from the index patients and medical personnel involved in their care were assessed by phage typing, polymerase chain reaction for exfoliative toxin genes, SmaI macro-restriction analysis and molecular spa-typing. These studies first revealed SA cultural growth in synovial fluid of all three patients as well as nasal mucosa of one medical assistant. Moreover, all SA isolates had the same phage typing and antibiotic susceptibilities and were positive for exfoliative toxin ETa by polymerase chain reaction. SmaI macro-restriction and spa-typing further confirmed all proband isolates to be identical.

CONCLUSION

These findings provide evidence that SA nasal colonization of otherwise healthy carriers is a risk factor for SA infections, including SSSS, in predisposed individuals.

Clostridium difficile ribotypes 001, 017, and 027 are associated with lethal C. difficile infection in Hesse, Germany

From January 2008 to April 2009, 72 cases of severe Clostridium difficile infection were reported from 18 different districts in the state of Hesse, Germany. A total of 41 C. difficile isolates from 41 patients were subjected to PCR ribotyping. PCR ribotype (RT) 027 was the most prevalent strain accounting for 24 of 41 (59%) of typed isolates, followed by RT 001 (eight isolates, 20%), RT 017 and 042 (two isolates each), and RT 003, 066, 078, 081, and RKI-034 (one isolate each). Eighteen patients had died within 30 days after admission. C. difficile was reported as underlying cause of or contributing to death in 14 patients, indicating a case fatality rate of 19%. The patients with lethal outcome attributable to C. difficile were 59-89 years-old (median 78 years). Ribotyping results were available for seven isolates associated with lethal outcome, which were identified as RT 027 in three and as RT 001 and 017 in two cases each. Our data suggest that C. difficile RT 027 is prevalent in some hospitals in Hesse and that, in addition to the possibly more virulent RT 027, other toxigenic C. difficile strains like RT 001 and 017 are associated with lethal C. difficile infections in this region.

Laboratory tools and strategies for methicillin-resistant Staphylococcus aureus screening, surveillance and typing: state of the art and unmet needs

The public health burden caused by methicillin-resistant Staphylococcus aureus (MRSA) infections is now widely recognized, and is a cause of public alarm. Effective MRSA risk management in the healthcare system as well as in the community should rely on accurate detection of reservoirs and sources of transmission, as well as on close monitoring of the impact of interventions on disease incidence and bacterial dissemination. MRSA carrier screening and disease surveillance, coupled with molecular typing, are key information tools for integrated MRSA control and individual risk assessment. These tools should be tailored to the distinct needs of local interventions and national prevention programmes. Surveillance schemes should primarily inform local staff and serve as quality assurance about MRSA risk management. New technologies, including the use of selective culture media and real-time PCR assays, allow faster detection of MRSA carriers upon admission or during stay in healthcare institutions. More research is needed to ascertain their cost-effectiveness for MRSA control. Likewise, tremendous progress has been made concerning molecular typing methods, with optimization and standardization of sequence-based technologies offering broad applicability and high throughput. However, no single S. aureus typing method is yet providing fully reliable information within the range of discrimination needed for public health action. Further refinement of genotyping methods and international harmonization of surveillance and typing schemes must be achieved to facilitate global MRSA control.

Emergence and spread of vancomycin resistance among enterococci in Europe

Vancomycin-resistant enterococci (VRE) first appeared in the late 1980s in a few European countries. Nowadays, six types of acquired vancomycin resistance in enterococci are known; however, only VanA and to a lesser extent VanB are widely prevalent. Various genes encode acquired vancomycin resistance and these are typically associated with mobile genetic elements which allow resistance to spread clonally and laterally. The major reservoir of acquired vancomycin resistance is Enterococcus faecium; vancomycin-resistant Enterococcus faecalis are still rare. Population analysis of E. faecium has revealed a distinct subpopulation of hospital-acquired strain types, which can be differentiated by molecular typing methods (MLVA, MLST) from human commensal and animal strains. Hospital-acquired E. faecium have additional genomic content (accessory genome) including several factors known or supposed to be virulence-associated. Acquired ampicillin resistance is a major phenotypic marker of hospital-acquired E. faecium in Europe and experience has shown that it often precedes increasing rates of VRE with a delay of several years. Several factors are known to promote VRE colonisation and transmission; however, despite having populations with similar predispositions and preconditions, rates of VRE vary all over Europe.

Emergence and spread of vancomycin resistance among enterococci in Europe

Nowadays, six types of acquired vancomycin resistance in enterococci are known; however, only VanA and to a lesser extent VanB are widely prevalent. Various genes encode acquired vancomycin resistance and these are typically associated with mobile genetic elements which allow resistance to spread clonally and laterally. The major reservoir of acquired vancomycin resistance is Enterococcus faecium; vancomycin-resistant Enterococcus faecalis are still rare. Population analysis of E. faecium has revealed a distinct subpopulation of hospital-acquired strain types, which can be differentiated by molecular typing methods (MLVA, MLST) from human commensal and animal strains. Hospital-acquired E. faecium have additional genomic content (accessory genome) including several factors known or supposed to be virulence-associated. Acquired ampicillin resistance is a major phenotypic marker of hospital-acquired E. faecium in Europe and experience has shown that it often precedes increasing rates of VRE with a delay of several years. Several factors are known to promote VRE colonisation and transmission; however, despite having populations with similar predispositions and preconditions, rates of VRE vary all over Europe.

Direct detection of methicillin-resistant Staphylococcus aureus in clinical specimens by a nucleic acid-based hybridisation assay

The occurrence of methicillin-resistant Staphylococcus aureus (MRSA) is still increasing worldwide and is associated with significant morbidity, mortality and hospital costs. Screening for MRSA plays a key role in limiting further nosocomial spread of this organism. Control measures require a rapid and sensitive test for direct detection of MRSA carriage. This study evaluated an easy-to-use PCR-hybridisation assay for the direct detection of MRSA in clinical swab specimens. In total, 508 pairs of swabs from 242 patients at risk for MRSA carriage were analysed by the standard culture method and the PCR assay. One swab was used for PCR and culture, while the second was used for culture only. Of the 508 pairs tested, 37 were positive by culture and 35 were positive by PCR. Among the 471 culture-negative specimens, 465 were negative by PCR and six were PCR-positive. The PCR assay had a sensitivity of 94.59%, a specificity of 98.73%, a positive predictive value of 85.37%, and a negative predictive value of 99.57%. The PCR-hybridisation assay enabled reliable detection of MRSA carriage in c. 4 h, thereby allowing its effective use in an MRSA control strategy.

A European laboratory network for sequence-based typing of methicillin-resistant Staphylococcus aureus (MRSA) as a communication platform between human and veterinary medicine – an update on SeqNet.org

Binary file ES_Abstracts_Final_ECDC.txt matches

[Occurrence of MRSA in pigs and in humans involved in pig production--preliminary results of a study in the northwest of Germany]

In 2007, 678 pigs of all age groups out of 347 different farms from Lower Saxony and Northrhine-Westphalia and 86 persons occupationally exposed to pigs were investigated for their nasal colonisation with methicillin-resistant Staphylococcus areus (MRSA) by the Field Station for Epidemiology of the University of Veterinary Medicine Hannover and the Robert Koch-Institute. At the individual animal level, a frequency of positive results of 13% (n = 85 positive animals) and at the herd level, a frequency of positive results of 18% (n = 62 positive herds) were found. All isolates were assigned to the Multilocus Sequence Typing Type ST398. Within MRSA-positive herds, there were more MRSA-negative than MRSA-positive animals. Among the occupationally exposed persons (veterinarians, laboratory personnel and meat inspection personnel), 20 persons (23%) showed a nasal colonisation with MRSA ST398. A quite strong association between the intensity of the contact to pigs with the frequency of nasal colonisation in the occupationally exposed persons was detected. None of the animals or the humans nasally colonised by MRSA ST398 showed any clinical symptoms of a staphylococcal infection. Conclusions are drawn on the herd and intra-herd prevalence of the nasal colonisation of pigs with MRSA ST398 in pigs, but especially on which questions need to be addressed by further research.

Community-associated methicillin-resistant Staphylococcus aureus ST8 ("USA300") in an HIV-positive patient in Cologne, Germany, February 2008

The first cases of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) were reported in 1996 in Minnesota, United States (US) and were deep-seated skin and soft tissue infections and a few cases of necrotising pneumonia, mainly in children and among the Native American population [1]. A few years later, a large outbreak of CA-MRSA infections was reported in the men who have sex with men (MSM) community in California, predominantly among human immunodeficiency virus (HIV)-positive patients; data on sexual transmission was not available [2]. A recent report on the spread of CA-MRSA, mainly due to the widely disseminated strain ""USA300"", in numerous MSM in San Francisco and in one patient in Boston suggested sexual transmission [3], but initiated critical reviews concerning the transmission route and the corresponding public health message [4,5].

A case of Clostridium difficile-associated disease due to the highly virulent clone of Clostridium difficile PCR ribotype 027, March 2007 in Germany

Here, we report the isolation of C. difficile PCR ribotype 027 from a patient suffering from pseudomembranous colitis in Germany in March 2007. The strain was identified during a retrospective PCR ribotyping survey of stored isolates.

Occurrence of the USA300 community-acquired Staphylococcus aureus clone in Austria

Methicillin-resistant Staphylococcus aureus isolates are emerging as significant pathogens in the community.

Management of a large healthcare-associated outbreak of Panton-Valentine leucocidin-positive meticillin-resistant Staphylococcus aureus in Germany

We report the largest documented healthcare-associated outbreak of Panton-Valentine leucocidin-positive meticillin-resistant Staphylococcus aureus (PVL(+) MRSA) in Europe. Six index patients from three long-term care facilities (LTCFs) were screened positive for PVL(+) MRSA in 2004 on admission to a community hospital in Germany. The purpose of this prospective study was to describe the prevalence of PVL(+) MRSA in the LTCFs before and after infection control interventions. Screening for MRSA with or without PVL was performed in all three LTCFs in 2004 [453 residents, 240 healthcare workers (HCWs)] and 2005 (440 residents, 192 HCWs). Swabs from anterior nares and wounds, if applicable, were collected. Colonised residents and staff were treated with mupirocin nasal ointment and topical antiseptics, and staff were provided with hygiene education. Total MRSA carrier rate of residents and HCWs in 2004 was 11.3% (PVL(+) MRSA 9.1%, PVL(-) MRSA 2.2%). There were comparable carrier rates between residents and HCWs in each LTCF. All PVL(+) MRSA isolates were of clonal origin (MLST 22) representing a novel spa sequence type t310. A decrease in total MRSA prevalence (from 11.3 to 5.5%) and PVL(+) MRSA (from 9.1 to 3.3%) was observed in 2005. The rate of PVL(-) MRSA remained unaffected. No symptomatic skin infections were noted among residents or HCWs. In this outbreak incomplete control of PVL(+) MRSA presumably resulted from difficult and delayed detection and decolonisation of carriers, incomplete compliance with control measures and lack of enforcement by public health authorities.

Prämedikation, prä- und postoperative Visite

Proceeding from German and English language textbooks on anaesthesia as sources, this article asks what concepts of preoperative and postoperative visits have dominated since 1880 and what types of premedication have been preferred. The idea of obligatory premedication became widespread in the first third of the twentieth century. The premedication approach was gradually supplanted by concepts of anaesthesia introduction (basal anaesthesia). The preoperative visit was usually a separate topic in the textbooks and the focus was on the patient's psyche. Much less attention was devoted to the postoperative visit. The current emphasis on the postoperative visit in the framework of perioperative anaesthesia is barely dealt with at all in the textbooks that were consulted.

Clonal distribution of superantigen genes in clinical Staphylococcus aureus isolates

Staphylococcus aureus is both a successful human commensal and a major pathogen. The elucidation of the molecular determinants of virulence, in particular assessment of the contributions of the genetic background versus those of mobile genetic elements (MGEs), has proved difficult in this variable species. To address this, we simultaneously determined the genetic backgrounds (spa typing) and the distributions of all 19 known superantigens and the exfoliative toxins A and D (multiplex PCR) as markers for MGEs. Methicillin- sensitive S. aureus strains from Pomerania, 107 nasal and 88 blood culture isolates, were investigated. All superantigen-encoding MGEs were linked more or less tightly to the genetic background. Thus, each S. aureus clonal complex was characterized by a typical repertoire of superantigen and exfoliative toxin genes. However, within each S. aureus clonal complex and even within the same spa type, virulence gene profiles varied remarkably. Therefore, virulence genes of nasal and blood culture isolates were separately compared in each clonal complex. The results indicated a role in infection for the MGE harboring the exfoliative toxin D gene. In contrast, there was no association of superantigen genes with bloodstream invasion. In summary, we show here that the simultaneous assessment of virulence gene profiles and the genetic background increases the discriminatory power of genetic investigations into the mechanisms of S. aureus pathogenesis.

Detection of low-level oxacillin resistance in mecA-positive Staphylococcus aureus

Detection of low-level oxacillin-resistant Staphylococcus aureus is a problem that needs special attention, particularly in relation to methicillin-resistant S. aureus (MRSA) strains in the community that belong to clonal lineage ST80. This study compared different phenotypic methods for the detection of 74 low-level oxacillin-resistant S. aureus strains (oxacillin MIC <or=1 mg/L), 46 MRSA strains (oxacillin MIC >or=2 mg/L) and 117 methicillin-susceptible S. aureus strains. Determination of microbroth dilution MICs for oxacillin was wholly unsatisfactory, and gave a limited specificity for cefoxitin. The sensitivity of disk-diffusion performed according to CLSI recommendations was 92% with an oxacillin 1-microg disk, and 96% with a cefoxitin 30-microg disk; use of a 10-microg cefoxitin disk and a semi-confluent inoculum (breakpoint for resistance <18 mm zone diameter) gave a sensitivity of 97%. When disk-diffusion was performed on IsoSensitest agar with a zone diameter breakpoint for resistance of <22 mm (as recommended by the Swedish Reference Group for Antibiotics), the sensitivity was 95%.

Community MRSA

Additional to epidemic methicillin resistant Staphylococcus aureus (haMRSA) which had been disseminated in and between hospitals, MRSA emerged in the community independent upon the nosocomial setting (caMRSA). caMRSA possess the capacity to form Panton-Valentine-Leukocidin (PVL) as a special virulence factor. In general PVL-positive S. aureus isolates are associated with necrotizing skin and soft tissue infections as well as with necrotizing pneumonia. caMRSA are less "broad" resistant against different groups of antibiotics as haMRSA and require special attention when performing antimicrobial susceptibility testing. Prevention of further dissemination of caMRSA requires appropriate diagnosis, therapy and sanitation of the carrier state. Hygienic measures have not only to be taken in ambulant treatment but also in households of affected patients.

Subtyping of ST22-MRSA-IV (Barnim epidemic MRSA strain) at a university clinic in Germany from 2002 to 2005

Emergence of the meticillin-resistant Staphylococcus aureus (MRSA) Barnim epidemic strain (ST22-MRSA-IV) was demonstrated recently at University Hospital in Magdeburg, Germany. To aid the study of transmission events, it is important to have an epidemiological typing method with the ability to distinguish among MRSA isolates. The aim of this study was to determine the ability of phenotypic and genotypic methods to type ST22-MRSA-IV strains within a hospital for microevolution events. Forty-two ST22-MRSA-IV strains collected from 2002 to 2005 were analysed using antimicrobial testing, toxin gene analysis, PFGE, spa typing, fluorescent amplified fragment length polymorphism (fAFLP) and determination of staphylococcal interspersed repeat units (SIRUs). Four different antimicrobial patterns were observed. The majority of the isolates (n=31) were resistant towards erythromycin, ciprofloxacin and clindamycin, in addition to penicillin and oxacillin. All strains harboured the sec gene and showed a homogeneous profile of toxin genes. One isolate was typed as spa t022, two as spa t474 and the remainder belonged to spa type t032. PFGE yielded eight profiles and SIRU typing resulted in six different patterns. The fAFLP technique subdivided the individual PFGE profiles, but the grouping of isolates differed from that obtained by PFGE or SIRU typing. These results showed a diversity of ST22-MRSA-IV strains within a narrow clinical setting, indicating microevolution of the Barnim MRSA clone. The ability to distinguish among MRSA strains within an endemic setting will lead to a greater understanding of the transmission of MRSA and is necessary to be able to control the spread of various clones.

[Control of methicillin-resistant S. aureus by active surveillance. Results of a workshop held by the Deutsche Gesellschaft für Hygiene und Mikrobiologie]

In Germany, methicillin-resistant S. aureus (MRSA) is increasing continuously. To control the spread of MRSA, active surveillance and admission screening are recommended. In most cases, screening cultures of patients at risk for MRSA will be sufficient. Screening of all patients admitted to an ICU is cost-effective when the incidence of MRSA and nosocomial MRSA infections is high (>2 cases/100 patients and 0.3 MRSA infections/100 patients, respectively): Under these circumstances, a decrease in the incidence of nosocomial MRSA infections of 50% leads to cost-effectiveness at costs of 16 Euro/sample (including subsequent costs). If the incidence of nosocomial MRSA infections decreases by 75%, costs of 24 Euro/sample (including subsequent costs) are cost-effective. If the incidence of MRSA is high, screening by PCR may be cost-effective for patients at high risk for MRSA, especially if they are isolated prophylactically. Recently, PCR methods have been developed which allow the specific identification of MRSA even from nasal swabs.

Assignment of Staphylococcus isolates to groups by spa typing, SmaI macrorestriction analysis, and multilocus sequence typing

The implementation of the new clustering algorithm Based Upon Repeat Pattern (BURP) into the Ridom StaphType software tool enables clustering based on spa typing data for Staphylococcus aureus. We compared clustering results obtained by spa typing/BURP to those obtained by currently well-established methods, i.e., SmaI macrorestriction analysis and multilocus sequence typing/eBURST. A total of 99 clinical S. aureus strains, including MRSA and representing major clonal lineages associated with important kinds of infections which have been prevalent in Germany and Central Europe during the last 10 years, were used for comparison. SmaI macrorestriction analysis revealed the highest discriminatory power, and clustering results for all three methods resulted in concordance values ranging from 96.8% between the two sequence-based methods to 93.4% between spa typing/BURP and SmaI macrorestriction/cluster analysis. The results of this study indicate that spa typing, together with BURP clustering, is a useful tool in S. aureus epidemiology, especially because of ease of use and the advantages of unambiguous sequence analysis as well as reproducibility and exchange of typing data.

Microarray-based characterisation of a Panton-Valentine leukocidin-positive community-acquired strain of methicillin-resistant Staphylococcus aureus

Recent years have witnessed the emergence of novel methicillin-resistant Staphylococcus aureus (MRSA) strains that produce the potent toxin Panton-Valentine leukocidin (PVL). PVL-positive strains can cause complicated skin infections or necrotising pneumonia with high mortality, and these strains have the potential for epidemic spread in the community. In 2004-2005, two case clusters and two isolated cases were observed in eastern Saxony and southern Brandenburg. These were the first known infections with PVL-positive community-acquired MRSA (caMRSA) in this part of Germany. The isolates belonged to agr type III, spa type 44 or spa type 131, and showed a SmaI macrorestriction pattern that corresponded to caMRSA of clonal group ST80. The isolates were susceptible to levofloxacin, macrolides, clindamycin, gentamicin and vancomycin. Most isolates showed resistance to tetracycline and fusidic acid because of the presence of the tetK and far1 genes. A novel plasmid (designated pUB102) harbouring far1, tetK and blaZ was characterised and partially sequenced. Microarray analysis revealed that the caMRSA isolates harboured genes encoding several bi-component toxins (lukF/S-PVL, lukD/E, lukS/F plus hlgA, and another putative leukocidin homologue). Neither tst1 nor genes for enterotoxins A-Y were detected, but the isolates harboured several staphylococcal enterotoxin-like toxin genes (set genes), as well as genes encoding an epidermal cell differentiation inhibitor (edinB) and exfoliative toxin D (etD). Comparative analysis of other isolates from Australia, Germany, Switzerland and the UK showed that these isolates were representative of a widespread clone of caMRSA.

Characterization of methicillin-resistant Staphylococcus aureus from Ulaanbaatar, Mongolia

In order to expand current knowledge of the types of methicillin-resistant Staphylococcus aureus (MRSA) strains circulating in central Asia, six MRSA strains collected from hospitals in Ulaanbaatar, Mongolia during 2000-2002 were examined. Three strains possessed a staphylococcal cassette chromosome mec (SCCmec) element of type IV c, were sequence type (ST) 154 according to multilocus sequence typing (MLST), and contained lukS-lukF (Panton-Valentine leukocidin). Another three strains contained a SCCmec element of type III and were MLST type ST 239. Using automated ribotyping, the six MRSA strains were divided into four different EcoRI ribotypes, and two groups of isolates were distinguished by means of SmaI-macrorestriction patterns. In comparison to other countries, the incidence of MRSA in Mongolia is low.

High interlaboratory reproducibility of DNA sequence-based typing of bacteria in a multicenter study

Current DNA amplification-based typing methods for bacterial pathogens often lack interlaboratory reproducibility. In this international study, DNA sequence-based typing of the Staphylococcus aureus protein A gene (spa, 110 to 422 bp) showed 100% intra- and interlaboratory reproducibility without extensive harmonization of protocols for 30 blind-coded S. aureus DNA samples sent to 10 laboratories. Specialized software for automated sequence analysis ensured a common typing nomenclature.

[Community-based MRSA. A new challenge for dermatology]

Treatment options for infections with MRSA are extremely limited because of resistance to all beta-lactam antibiotics and primarily because of the fast acquisition of further antibiotic resistance. During the past six years MRSA possessing the genomic determinant of an additional virulence factor emerged. This virulence factor, Panton-Valentine-Leukocidin, seems to be responsible for deep skin infections as well as necrotizing pneumonia. In order to avoid a continuous spread of MRSA, consequent prevention measures both in dermatological practices and for colonized patients in their general environment are essential.