Dissemination of Klebsiella pneumoniae ST147 NDM-1 in Poland, 2015-19.

OBJECTIVES: To assess the spread of New Delhi metallo-ß-lactamase-1 (NDM-1)-producing Klebsiella pneumoniae ST147 organisms in Poland since an introduction from Tunisia in March 2015, including their phylogenetic position in the global population of the high-risk clone. METHODS: Out of 8925 unique NDM-positive K. pneumoniae isolates identified in Poland from April 2015 till December 2019, 126 isolates, including the Tunisian imports, were related by PFGE and blaNDM gene-carrying Tn125 transposon derivatives. Forty-seven representative isolates were sequenced by Illumina MiSeq. The phylogeny, resistome, virulome and plasmid replicons were analysed and compared with the international ST147 strains. Plasmids of six isolates were studied by the MinION sequencing. RESULTS: A high homogeneity of the 47 isolates was observed, with minor variations in their resistomes and plasmid replicon profiles. However, the detailed SNP comparison discerned a strict outbreak cluster of 40 isolates. All of the organisms were grouped within the ST147 phylogenetic international lineage, and four NDM-1 producers from Tunisia, Egypt and France were the closest relatives of the Polish isolates. Yersiniabactin genes (YbST280 type) were located within the ICEKpn12-like element in most of the outbreak isolates, characterized by O2v1 and KL64 antigen loci. The blaNDM-1 genes were located in double-replicon IncFIIK2+IncFIBK plasmids. CONCLUSIONS: The continuous spread of K. pneumoniae ST147 NDM-1 in Poland since 2015, largely in the Warsaw area, is demonstrated by this genomic analysis. The isolates showed a high degree of homogeneity, and close relatedness to organisms spreading in the Mediterranean region.

Cutaneous ulcers revealing diphtheria: A re-emerging disease imported from Indian Ocean countries?

INTRODUCTION: Diphtheria due to Corynebacteriumdiphtheriae (C. diphtheriae) has become rare in developed countries. In France only 10 cases of toxigenic diphtheria have been reported since 1989, in all cases causing pharyngitis and all emanating from endemic countries with exception of one contact case. We report herein 13 cases with cutaneous diphtheria, in 5 of which diphtheria toxin was produced, and all imported into France between 2015 and 2018. OBSERVATIONS: Thirteen patients aged 4 to 77 years presented painful and rapidly progressive round ulcerations of the legs, that were superficial and in some cases purulent, with an erythematous-purple border covered with greyish membrane. Bacteriological sampling of ulcers revealed the presence of C. diphtheriae. Only 6 patients had been properly immunized over the preceding 5 years. DISCUSSION: These cases underline the resurgence of cutaneous diphtheria and the circulation of toxigenic strains in France following importation from Indian Ocean countries. This may constitute an important reservoir for ongoing transmission of the disease. Re-emergence of this pathogen stems from the current migratory flow and decreased adult booster coverage. CONCLUSION: Cutaneous diphtheria should be considered in cases of rapidly developing painful skin ulcers with greyish membrane, especially among patients returning from endemic areas, regardless of their vaccination status. The clinician should order specific screening for C. diphtheriae from the bacteriologist, since with routine swabbing Corynebacteriaceae may be reported simply as normal skin flora. Vaccination protects against toxigenic manifestations but not against actual bacterial infection. Early recognition and treatment of cutaneous diphtheria and up-to-date vaccination are mandatory to avoid further transmission and spread of both cutaneous and pharyngeal diphtheria.

Genomic background of the Klebsiella pneumoniae NDM-1 outbreak in Poland, 2012-18.

OBJECTIVES: To characterize genomes of Klebsiella pneumoniae ST11 NDM-1 responsible for a countrywide outbreak in Poland and compare them phylogenetically with other Polish and international ST11 strains. METHODS: Seventy-one carbapenemase-producing K. pneumoniae ST11 isolates from Poland, including 66 representatives of the NDM-1 epidemic from 2012-18, were sequenced using Illumina MiSeq. Additionally, three outbreak isolates were also sequenced using MinION. The clonality and phylogenetic analysis was done by core-genome MLST and SNP approaches. Resistomes, virulomes, K/O antigens and plasmid replicons were screened for. The detailed plasmid analysis was based on full assemblies using Oxford Nanopore Technologies data. RESULTS: Chromosomes of the outbreak isolates formed an essentially homogeneous cluster (though accumulating SNPs gradually with time), differing remarkably from other Polish NDM-1/-5-, KPC-2- or OXA-48-producing K. pneumoniae ST11 strains. The cluster belonged to a clade with 72 additional isolates identified worldwide, including closely related NDM-1 producers from several countries, including organisms from Bulgaria and Greece. All these had KL24 and O2v1 antigens and the chromosomal yersiniabactin locus YbST230 residing in the ICEKp11 element. The specific blaNDM-1-carrying Tn125 transposon derivative, named Tn125A, was located in IncFII/pKPX-1- and/or IncR-like plasmids; however, the IncRs rearranged extensively during the outbreak, contributing to highly dynamic plasmid profiles and resistomes. CONCLUSIONS: The K. pneumoniae ST11 NDM-1 genotype that has been expanding in Poland since 2012 is largely monoclonal and represents a novel international high-risk lineage that is also spreading in other countries.

Phylogenetic lineages, clones and ß-lactamases in an international collection of Klebsiella oxytoca isolates non-susceptible to expanded-spectrum cephalosporins.

OBJECTIVES: The objective of this study was to examine Klebsiella oxytoca clonal and phylogenetic diversity, based on an international collection of carriage isolates non-susceptible to expanded-spectrum cephalosporins (ESCs). METHODS: The study material comprised 68 rectal carriage K. oxytoca isolates non-susceptible to ESCs recovered in 2008-11 from patients in 14 hospitals across Europe and Israel. ESC resistance was tested phenotypically; genes encoding ESBLs, AmpC cephalosporinases and carbapenemases were amplified and sequenced. The isolates were typed by PFGE and MLST, followed by sequencing of blaOXY genes. RESULTS: MLST and PFGE distinguished 34 STs and 47 pulsotypes among the isolates, respectively. Six STs were split into several pulsotypes each. Five STs were more prevalent (n = 2-9) and occurred in several countries each, including ST2, ST9 and ST141, which belong to a growing international clonal complex (CC), CC2. Four phylogenetic lineages were distinguished, each with another type of chromosomal OXY-type ß-lactamase. Three of these, with OXY-1/-5, OXY-2 types and OXY-4, corresponded to previously described phylogroups KoI, KoII and KoIV, respectively. A single isolate from Israel represented a distinct lineage with a newly defined OXY-7 type. The phylogroups showed interesting differences in mechanisms of ESC resistance; KoI strains rarely overexpressed the OXY enzymes but commonly produced ESBLs, whereas KoII strains often were OXY hyperproducers and carried ESBLs much less frequently. AmpCs (DHA-1) and carbapenemases (VIM-1) occurred sporadically. CONCLUSIONS: The study confirmed the high genetic diversity of the collection of K. oxytoca ESC-non-susceptible isolates, composed of phylogroups with distinct types of OXY-type ß-lactamases, and revealed some STs of broad geographical distribution.

The emergence of multidrug-resistant Klebsiella pneumoniae of international clones ST13, ST16, ST35, ST48 and ST101 in a teaching hospital in the Paris region.

Despite infection control measures, an important increase in the extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae incidence density occurred in our hospital from 2006 onwards. This study, focusing on the 2005-2007 period, was performed in an attempt to explain this increase. ESBLs were characterized, isolates were typed by ERIC2-PCR, and sequence type (ST) of clustered isolates was determined. Temporal-spatial relationships of patients were analysed to assess possible cross-contamination. Of the 74 ESBL-producing isolates, 30 (40%) were detected at admission, 53 (71∙5%) produced CTX-M enzymes, 40 displayed unique ERIC2-PCR profiles and 34 were assigned into six clusters: ST16 (n=21), ST101, ST48, ST35, ST13, and ST436. Relationships were identified in 22 of the 34 patients harbouring clustered isolates. This study highlights the complex epidemiology of ESBL-producing K. pneumoniae in the mid-2000s with potential cross-contamination for only 30% of the 74 patients in our hospital, and the emergence of clones that are currently spreading worldwide.

Human leptospira isolates circulating in Mayotte (Indian Ocean) have unique serological and molecular features.

Leptospirosis is one of the most widespread zoonoses in the world. However, there is a lack of information on circulating Leptospira strains in remote parts of the world. We describe the serological and molecular features of leptospires isolated from 94 leptospirosis patients in Mayotte, a French department located in the Comoros archipelago, between 2007 and 2010. Multilocus sequence typing identified these isolates as Leptospira interrogans, L. kirschneri, L. borgpetersenii, and members of a previously undefined phylogenetic group. This group, consisting of 15 strains, could represent a novel species. Serological typing revealed that 70% of the isolates belonged to the serogroup complex Mini/Sejroe/Hebdomadis, followed by the serogroups Pyrogenes, Grippotyphosa, and Pomona. However, unambiguous typing at the serovar level was not possible for most of the strains because the isolate could belong to more than one serovar or because serovar and species did not match the original classification. Our results indicate that the serovar and genotype distribution in Mayotte differs from what is observed in other regions, thus suggesting a high degree of diversity of circulating isolates worldwide. These results are essential for the improvement of current diagnostic tools and provide a starting point for a better understanding of the epidemiology of leptospirosis in this area of endemicity.

Multilocus microsatellite markers for molecular typing of Candida glabrata: application to analysis of genetic relationships between bloodstream and digestive system isolates.

Candida glabrata has emerged as the second most common etiologic agent, after Candida albicans, of superficial and invasive candidiasis in adults. Strain typing is essential for epidemiological investigation, but easy-to-use and reliable typing methods are still lacking. We report the use of a multilocus microsatellite typing method with a set of eight markers on a panel of 180 strains, including 136 blood isolates from hospitalized patients and 34 digestive tract isolates from nonhospitalized patients. A total of 44 different alleles were observed, generating 87 distinct genotypes. In addition to perfect reproducibility, typing ability, and stability, the method had a discriminatory power calculated at 0.97 when all 8 markers were associated, making it suitable for tracing strains. In addition, it is shown that digestive tract isolates differed from blood culture isolates by exhibiting a higher genotypic diversity associated with different allelic frequencies and preferentially did not group in clonal complexes (CCs). The demonstration of the occurrence of microevolution in digestive strains supports the idea that C. glabrata can be a persistent commensal of the human gut.

Re-emergence of Corynebacterium diphtheriae.

BACKGROUND: Diphtheria is re-emerging in Europe. A total of 36 cases were reported in Europe in 2015 versus 53 cases between 2000 and 2009. PATIENTS: We report two cases of Corynebacterium diphtheriae infection in a French hospital in 2016: a cutaneous infection with negative toxin testing in a French traveller, and a respiratory diphtheria carriage with positive toxin testing in an Afghan refugee diagnosed with pulmonary tuberculosis. The vaccination history of the Afghan patient could not be retrieved.

Guidelines for the validation and application of typing methods for use in bacterial epidemiology.

For bacterial typing to be useful, the development, validation and appropriate application of typing methods must follow unified criteria. Over a decade ago, ESGEM, the ESCMID (Europen Society for Clinical Microbiology and Infectious Diseases) Study Group on Epidemiological Markers, produced guidelines for optimal use and quality assessment of the then most frequently used typing procedures. We present here an update of these guidelines, taking into account the spectacular increase in the number and quality of typing methods made available over the past decade. Newer and older, phenotypic and genotypic methods for typing of all clinically relevant bacterial species are described according to their principles, advantages and disadvantages. Criteria for their evaluation and application and the interpretation of their results are proposed. Finally, the issues of reporting, standardisation, quality assessment and international networks are discussed. It must be emphasised that typing results can never stand alone and need to be interpreted in the context of all available epidemiological, clinical and demographical data relating to the infectious disease under investigation. A strategic effort on the part of all workers in the field is thus mandatory to combat emerging infectious diseases, as is financial support from national and international granting bodies and health authorities.

Identification of coagulase-negative staphylococci other than Staphylococcus epidermidis by automated ribotyping.

As routine identification of coagulase-negative staphylococci is problematic, the performance of automated ribotyping was evaluated for identification of coagulase-negative staphylococci other than Staphylococcus epidermidis. In total, 177 isolates were tested, comprising 149 isolates from blood samples, 15 isolates that were not identified by internal transcribed spacer (ITS)-PCR in a previous study, and 13 reference strains. The identification results were compared with those obtained by the API 20 Staph system, with standard phenotypic and molecular methods as reference. Most (n = 166; 93.8%) isolates were identified correctly by automated ribotyping. For 61 isolates, API 20 Staph and ribotyping were in agreement, but for 105 isolates, ribotyping provided correct identification and API 20 Staph did not. Four isolates not identified by automated ribotyping were recognised correctly by API 20 Staph. The remaining seven isolates could not be identified by either of the two methods. Automated ribotyping was able to distinguish Staphylococcus capitis reliably from Staphylococcus caprae. The results demonstrate the value of automated ribotyping for identification of coagulase-negative Staphylococcus (CoNS) isolates from human sources and may help to clarify the clinical relevance of CoNS species. In addition, automated ribotyping was able to detect polymorphisms that may be useful for epidemiological purposes within S. capitis, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus simulans, S. caprae, Staphylococcus warneri, Staphylococcus lugdunensis, Staphylococcus schleiferi, Staphylococcus sciuri, Staphylococcus pasteuri and Staphylococcus xylosus.

Identification of six Trypanosoma cruzi lineages by sequence-characterised amplified region markers.

Six discrete phylogenetic lineages were recently identified in Trypanosoma cruzi, on the basis of multilocus enzyme electrophoresis and random amplified polymorphic DNA (RAPD) characterisation. The objective of the present study was to develop specific PCR-based markers for the identification of each of the six lineages. Eighty-seven T. cruzi stocks representative of all the lineages were characterised by RAPD with three primers, resulting in the identification of three fragments that were specifically amplified in the given sets of lineages. After cloning and sequencing these fragments, three pairs of sequence-characterised amplified region (SCAR) primers were designed. After PCR amplification using the SCAR primers, the initial polymorphism was retained either as the presence or absence of amplification, or as size variation between the PCR products. Although most PCR products, taken individually, were distributed across several lineages, the combination of the three SCAR markers resulted in characteristic patterns that were distinct in the six lineages. Furthermore, T. cruzi lineages were distinguished from Trypanosoma rangeli, T. cruzi marinkellei and T. cruzi-like organisms. The excellent correspondence of these new PCR markers with the phylogenetic lineages, allied with their sensitivity, makes them reliable tools for lineage identification and strain characterisation in T. cruzi. The approach described here could be generalised to any species of microorganism harbouring clear-cut phylogenetic subdivisions.

A phylogenetic analysis of the Trypanosoma cruzi genome project CL Brener reference strain by multilocus enzyme electrophoresis and multiprimer random amplified polymorphic DNA fingerprinting.

We have assessed the phylogenetic status of the Trypanosoma cruzi Genome Project CL Brener reference strain by multilocus enzyme electrophoresis (MLEE) and multiprimer random amplified polymorphic DNA (RAPD) including a set of cloned stocks representative of the whole genetic diversity of T. cruzi. MLEE and RAPD data gave congruent phylogenetic results. The CL Brener reference strain fell into the second major phylogenetic subdivision of T. cruzi, and was genetically very close to the Tulahuen reference strain. No reliable RAPD character and only one MLEE character permitted us to distinguish between the CL Brener and Tulahuen reference strains. In contrast, many RAPD and MLEE characters were able to distinguish between the CL Brener reference strain and the other T. cruzi genotypes analyzed here, in particular the formerly described principal zymodemes I, II and III. It is suspected that both CL Brener and Tulahuen are hybrid genotypes, a fact that should be taken into account when interpreting sequence data. Moreover, our study confirms that the species T. cruzi is genetically very heterogeneous. We recommend future comparison of sequencing data from the CL Brener reference strain with those of at least one radically distinct T. cruzi genotype, belonging to the other major phylogenetic subdivision of this species.

Identification of six Trypanosoma cruzi phylogenetic lineages by random amplified polymorphic DNA and multilocus enzyme electrophoresis.

Genetic characterisation of Trypanosoma cruzi variants is of foremost importance, due to considerable genetic and biological heterogeneity in the parasite populations. Two major phylogenetic lineages, each highly heterogeneous, have been previously described within this species. Here we characterised a geographically and ecologically diverse sample of stocks representative of the breadth of the known clonal diversity of each major lineage, using random amplified polymorphic DNA with 20 primers and multilocus enzyme electrophoresis at 22 loci. Molecular hybridisation experiments were performed to control the homology of randomly amplified DNA markers. Both sets of data were highly consistent and supported the existence of two major lineages. Additionally, we found that lineage 2 appeared further partitioned into five sharply delineated phylogenetic clusters, each comprising one of the following reference strains: CanIII cl1 (Z3 reference), M5631 cl5, Esmeraldo cl3 (Z2 reference), CL Brener, and MN cl2. The two first clusters were found mainly in sylvatic environments, whereas the three latter were restricted to domestic transmission cycles and were only collected South to the Amazon Basin. In contrast, lineage 1, which included Miles' Z1 reference strain X10 cl1, was not further subdivided and was encountered across the entire endemic area, in both domestic and sylvatic cycles. Thus, T. cruzi appeared to be subdivided into six discrete typing units, or DTUs, exhibiting distinct geographic and ecological ranges. Reliable diagnostic markers for the two major lineages and the five smaller DTUs of lineage 2 are described, and correspondence with previous classifications of T. cruzi genotypes is given in order to help communication on T. cruzi phylogenetic diversity.

Characterisation of large and small subunit rRNA and mini-exon genes further supports the distinction of six Trypanosoma cruzi lineages.

It has been proposed that isolates of Trypanosoma cruzi, the agent of American trypanosomiasis, can be ordered into two primary phylogenetic lineages, first based on multilocus enzyme electrophoresis and random amplified polymorphic DNA, and subsequently based on the 24Salpha rRNA and mini-exon genes. Recent multilocus enzyme electrophoresis and random amplified polymorphic DNA data have additionally shown that the major multilocus enzyme electrophoresis/random amplified polymorphic DNA lineage II is further subdivided into five smaller lineages, designated IIa-IIe. In this study, the precise correspondence between the multilocus enzyme electrophoresis/random amplified polymorphic DNA and rRNA/mini-exon lineages was investigated. Using the 24Salpha rRNA and mini-exon markers in combination, five sets of strains were distinguished, corresponding to the multilocus enzyme electrophoresis/random amplified polymorphic DNA lineages I, IIa, IIc, IId and to lineages IIb/IIe together, respectively. The previous categorisation into only two primary lineages based on 24Salpha rRNA and mini-exon characterisation is explained, in part, by the lack of representativeness of the breadth of T. cruzi diversity in earlier study samples. Additionally, a PCR assay based on a length-variable region of the 18S rRNA gene distinguished lineage IIe from lineage IIb. Thus, the six multilocus enzyme electrophoresis/random amplified polymorphic DNA lineages could be readily identified by combining data from the 24Salpha rRNA, mini-exon and 18S rRNA characterisation assays, further supporting the relevance of these genetic units for T. cruzi strain classification and subspecific nomenclature. The recently proposed groups T. cruzi I and T. cruzi II correspond to multilocus enzyme electrophoresis/random amplified polymorphic DNA lineages I and IIb, respectively. Our findings show that T. cruzi lineage characterisation based on a single marker (either mini-exon or 24Salpha rRNA) has insufficient resolution, and leads to important reinterpretations of recent epidemiological and evolutionary studies based on the oversimplified rRNA/mini-exon dichotomic classification of T. cruzi isolates.

Phylogenetic diversity of bat trypanosomes of subgenus Schizotrypanum based on multilocus enzyme electrophoresis, random amplified polymorphic DNA, and cytochrome b nucleotide sequence analyses.

Trypanosome stocks isolated from bats (Chiroptera) and belonging to the subgenus Schizotrypanum were analyzed by multilocus enzyme electrophoresis (MLEE) at 22 loci, random amplified polymorphic DNA (RAPD) with 14 primers and/or cytochrome b nucleotide sequence. Bat trypanosomes belonged to the species Trypanosoma cruzi marinkellei (10 stocks), Trypanosoma dionisii (four stocks) and Trypanosoma vespertilionis (three stocks). One T. rangeli stock and seven stocks of T. cruzi sensu stricto, the agent of Chagas disease, were included for comparison. The homology of several RAPD fragments shared by distinct species was verified by hybridization. The sequence of a 516-nucleotide portion of the maxicircle-encoded cytochrome b (CYb) coding region was determined in representative stocks of the species under study. Phylogenetic analysis of the data confirmed the previous taxonomic attribution of these bat trypanosomes based on biological, epidemiological and ecological features. However, a new finding was that within T. cruzi marinkellei two major subdivisions could be distinguished, T.c.m. I, found in the spear-nose bats Phyllostomus discolor and Phyllostomus hastatus, and T.c.m. II, from P. discolor. In addition, the T. c. marinkellei 'Z' stock from a short-tailed bat (Carollia perspicillata) was distantly related to these two subdivisions, and the monophyly of T. c. marinkellei is unclear based on the present data. Based on the present sample, the European species T. dionisii and T. vespertilionis appeared to be more homogeneous. RAPD and CYb data both suggested the monophyly of a group composed of T. cruzi and the two major subdivisions of T. cruzi marinkellei. This study shows that MLEE, RAPD and CYb can be used for taxonomic assignment and provide valuable phylogenetic information for strains and taxa within the subgenus Schizotrypanum. An evolutionary scenario in which the broad host-range parasite T. cruzi would be derived from a bat-restricted trypanosome ancestor is discussed.

Development of a rapid identification method for Klebsiella pneumoniae phylogenetic groups and analysis of 420 clinical isolates.

A rapid method combining gyrA PCR-restriction fragment length polymorphism analysis, parC PCR and adonitol fermentation was developed to identify Klebsiella pneumoniae phylogenetic groups KpI, KpII and KpIII. Analysis of 420 clinical isolates from 26 hospitals showed that the three groups were widespread geographically. KpI comprised 80.3% of 305 isolates from blood and 82.2-97.2% of isolates from other clinical sources. KpIII was never found among isolates from urinary tract infections. KpI isolates from blood were generally less susceptible than KpIII isolates to the ten antimicrobial agents tested, with KpII being intermediate. The frequencies of ceftazidime resistance were 21.6% and 8.6% in KpI and KpIII isolates, respectively (p 0.01).

Molecular epidemiology of quinolone resistance and comparative in vitro activities of new quinolones against European Staphylococcus aureus isolates.

UNLABELLED: New fluoroquinolones (FQ) may possibly be used as alternative therapeutic options for Staphylococcus aureus infections. Our objectives were: (1) to define the in vitro activities of seven FQs in a collection of 434 methicillin-susceptible and 457 methicillin-resistant S. aureus from 23 European university hospitals; (2) to characterise the prevalence of mutations in the grlA and gyrA genes in all ciprofloxacin-resistant (n=433) isolates of S. aureus; (3) to determine the percentage of ciprofloxacin-resistant S. aureus strains with measurable quinolone efflux. METHODS: (1) The in vitro activities of different FQs were determined by microdilution tests. (2) PCR-amplified DNA was sequenced. (3) Ciprofloxacin minimum inhibitory concentrations (MIC) were determined in the presence and absence of reserpine, which inhibits efflux pumps. RESULTS: (1) Irrespective of the methicillin resistance of the isolates, sitafloxacin and clinafloxacin showed the best in vitro activities. (2) All ciprofloxacin-resistant isolates exhibited GrlA alterations, namely Ser-80-->Phe or Tyr or Glu-84-->Lys or Ala-116-->Glu or Pro or a combination of Ser-80-->Phe and Glu-84-->Val. These alterations in GrlA were combined with alterations in GyrA, namely Ser-84-->Leu or Lys or Glu-88-->Lys or Val. (3) Reserpine reduced ciprofloxacin MIC values in ca. 30% of the clinical isolates tested. CONCLUSIONS: (1) This current European overview of mutations involved in FQ resistance demonstrates that only a limited number of classical mutations in grlA and gyrA contributed to resistance in clinical isolates. (2) An efflux pump is involved in ca. 30% of ciprofloxacin-resistant S. aureus isolates. (3) Sitafloxacin and clinafloxacin are two very promising new FQs with good anti-staphylococcal activity. New FQs, perhaps in combination with efflux pump inhibitors, might play a role in the treatment of S. aureus infections.

Outbreak of a susceptible strain of Acinetobacter species 13 (sensu Tjernberg and Ursing) in an adult neurosurgical intensive care unit.

Between December 1999 and June 2000, an outbreak caused by Acinetobacter emerged on the neurosurgical intensive care unit of our hospital. It was shown using automated ribotyping using Eco RI and pulsed-field gel electrophoresis that the outbreak was caused by spread of a single strain, which was identified by ribotyping and amplified ribosomal DNA restriction analysis as Acinetobacter DNA group 13TU (sensu Tjernberg and Ursing). The outbreak strain, which showed no antibiotic resistance, was identified in 23 patients, five of whom developed an infection. The organism was also isolated from various environmental sites. Cross-transmission among patients continued despite contact isolation of colonized patients and reinforcement of basic disinfection procedures. Eventually, after implementation of additional stringent measures such as cohorting of positive patients and daily disinfection of the floor, the outbreak was brought under control. This study demonstrates that apart from Acinetobacter baumanii, Acinetobacter 13TU strains, even when they are fully susceptible, may cause outbreaks that are difficult to control. Correct identification to the species level of Acinetobacter by genotypic methods is necessary to get insight in the importance of the different Acinetobacter genomic species in hospital epidemiology.

A phylogenetic analysis by multilocus enzyme electrophoresis and multiprimer random amplified polymorphic DNA fingerprinting of the Leishmania genome project Friedlin reference strain.

We have assessed the phylogenetic status of the Leishmania genome project Friedlin reference strain by MLEE and multiprimer RAPD including a set of 9 stocks representative of the main Leishmania species and of the whole genetic diversity of the Leishmania genus. To our knowledge, the detailed genetic characterization of the Friedlin strain has never been published before. As previously recorded (Tibayrenc et al. 1993), MLEE and RAPD data gave congruent phylogenetic results. The Friedlin reference strain was definitely attributed to Leishmania (Leishmania) major Yakimoff et Schokhor, 1914. Five specific RAPD patterns made it possible to distinguish between the Friedlin strain and the 2 other L. (L.) major stocks included in the study. Various specific MLEE and RAPD characters permitted to distinguish between the Leishmania species included in the study. All these characters are usable to detect accidental laboratory mix-ups involving the Friedlin reference strain. In confirmation with previous studies involving a more limited set of genetic markers, the general genetic diversity of the Leishmania genus proved to be considerable. It must be made clear that only one strain cannot be considered as representative of the whole genetic variability of the genus Leishmania. In the future, it is therefore advisable to complement the results obtained in the framework of the Leishmania genome project with data from other strains that should be selected on a criterion of important genetic differences with the Friedlin strain.