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1.
Microbiol Insights ; 13: 1178636120977481, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33328737

RESUMO

Timely and reliable laboratory diagnostics is a necessity for patient safety and good patient management. Success in external quality assessment (EQA) reflects on the everyday work in a clinical laboratory. This study evaluated the reliability of serological point-of-care (POC) testing for the Epstein-Barr virus (EBV) that causes infectious mononucleosis (IM). Data from the results of 95 external quality control (EQC) samples, altogether 18 885 results during an eight-year period (2010-2017) were collected from 273 Finnish testing sites. Diagnosing acute infectious mononucleosis (EBV IM) is based on clinical, haematological and serological findings. Heterophile antibody tests are used for this purpose because they can be carried out at POC and are cheap and robust to perform. In this study, the data showed that the testing sites used 3 test methods and 17 different test kits; of the kits, 4 were used during the whole study period. The most commonly used test methods were immunochromatographic assays (12 test kits, 17 959 EQC results). Latex agglutination (4 test kits, 504 results) and immunofiltration test methods (one kit, 422 results) were also used. The overall success rate was 99.3% (for positive samples 99.6%, for negative samples 99.1%). The success rates of the different test methods varied from 94.3% for the immunofiltration method to 99.6% for the latex agglutination method. The lowest success rates were found for negative samples: 82.0% (QuickVue, Quidel [immunochromatographic method]), 91.3% (RDT EBV IgM Assay, Bio-Rad [immunofiltration method]). The results of the negative samples that represented old EBV immunity were the most difficult to interpret with a success rate of 98.9% compared to success rates of clearly positive (99.6%) and negative (99.5%) samples (P < .001). Especially the immunofiltration method (RDT EBV IgM Assay) produced 13.7% false positive results for samples of old immunity. The data showed that 42 of the studied 95 EBV IM EQA rounds were reported as expected (true positive or true negative) by all testing sites.

2.
Rheumatol Int ; 37(11): 1863-1869, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918489

RESUMO

Yersinia enterocolitica (YE) biotype 1A is generally considered non-pathogenic, and the role of it in causing reactive musculoskeletal complications is unclear. We evaluated the capability of YE biotype 1A to induce reactive arthritis (ReA) and other reactive musculoskeletal symptoms. Analysis of self-reported musculoskeletal symptoms was supplemented with a telephone interview (with a permission to acquire copies of patient files from a local physician or hospital) and/or clinical examination of subjects with recent musculoskeletal symptoms after a positive stool culture for YE. The diagnoses of ReA and reactive tendinitis and enthesitis (ReTe) were defined as "definite" when based on clinical examination and/or on interview by phone and "probable" when based solely on the questionnaire. Of 120 subjects, who reported musculoskeletal symptoms, 100 were included in the final analysis. Among these 100 patients, 68% had YE biotype 1A, 16% YE bio/serotype 4, and 1% biotype 2 infection; the remaining 15% had different YE-like strains or a non-biotypable strain. Of the 21 patients with ReA and of the 14 patients with ReTe, the diagnosis was definite in 9 and 7 patients and probable in 12 and 7 patients, respectively. The clinical picture of ReA caused by YE biotype 1A was similar with other bio/serotypes of YE. The definite ReA due to YE biotype 1A occurred in middle-aged adults (5 men, 4 women) with the most frequently affected joints being the knees and ankles. We suggest that YE biotype 1A should be taken into account as a new trigger of ReA.


Assuntos
Artrite Reativa/microbiologia , Yersinia enterocolitica/classificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reativa/etiologia , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proibitinas , Adulto Jovem
3.
Microbiol Insights ; 10: 1178636117691253, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28469461

RESUMO

In Finland, all laboratories carrying out diagnostics of infectious diseases in humans are approved by the Regional State Administrative Agencies and are obligated to participate in External Quality Assurance rounds. Performance in these rounds is thought to reflect the quality of laboratory work. In the 6-year study period, 17 Finnish laboratories received 48 simulated faecal specimens for the culturing of diarrhoeal pathogens, yielding altogether 586 faecal culture External Quality Control specimens and 581 reports. The results were correct in 92% of all reports and in 67% of all specimens. False-negative Salmonella results were given for 2 of the 18 specimens, one with biochemically atypical Salmonella strain and the other with a low count of Salmonella cells. False-negative Shigella report was given for 6 of the 7 specimens in some participating laboratory. Detection of all common faecal pathogens is especially relevant to patient safety, public health, and epidemiological surveillance.

4.
Emerg Infect Dis ; 22(7): 1216-20, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27314874

RESUMO

During summer 2014, a total of 89 Vibrio infections were reported in Sweden and Finland, substantially more yearly infections than previously have been reported in northern Europe. Infections were spread across most coastal counties of Sweden and Finland, but unusually, numerous infections were reported in subarctic regions; cases were reported as far north as 65°N, ≈100 miles (160 km) from the Arctic Circle. Most infections were caused by non-O1/O139 V. cholerae (70 cases, corresponding to 77% of the total, all strains were negative for the cholera toxin gene). An extreme heat wave in northern Scandinavia during summer 2014 led to unprecedented high sea surface temperatures, which appear to have been responsible for the emergence of Vibrio bacteria at these latitudes. The emergence of vibriosis in high-latitude regions requires improved diagnostic detection and clinical awareness of these emerging pathogens.


Assuntos
Raios Infravermelhos , Vibrioses/microbiologia , Vibrio/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Finlândia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Suécia/epidemiologia , Fatores de Tempo , Vibrio/classificação , Vibrioses/epidemiologia , Adulto Jovem
5.
PLoS One ; 10(11): e0142367, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26556595

RESUMO

Escherichia coli amine oxidase (ECAO), encoded by the tynA gene, catalyzes the oxidative deamination of aromatic amines into aldehydes through a well-established mechanism, but its exact biological role is unknown. We investigated the role of ECAO by screening environmental and human isolates for tynA and characterizing a tynA-deletion strain using microarray analysis and biochemical studies. The presence of tynA did not correlate with pathogenicity. In tynA+ Escherichia coli strains, ECAO enabled bacterial growth in phenylethylamine, and the resultant H2O2 was released into the growth medium. Some aminoglycoside antibiotics inhibited the enzymatic activity of ECAO, which could affect the growth of tynA+ bacteria. Our results suggest that tynA is a reserve gene used under stringent environmental conditions in which ECAO may, due to its production of H2O2, provide a growth advantage over other bacteria that are unable to manage high levels of this oxidant. In addition, ECAO, which resembles the human homolog hAOC3, is able to process an unknown substrate on human leukocytes.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Leucócitos/metabolismo , Monoaminoxidase/metabolismo , Sítios de Ligação , Proteínas de Escherichia coli/genética , Humanos , Peróxido de Hidrogênio/metabolismo , Monoaminoxidase/genética , Organismos Geneticamente Modificados , Oxirredução
6.
PLoS One ; 10(8): e0135936, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26313149

RESUMO

BACKGROUND: Shigatoxigenic Escherichia coli (STEC) and enterotoxigenic E. coli (ETEC) cause serious foodborne infections in humans. These two pathogroups are defined based on the pathogroup-associated virulence genes: stx encoding Shiga toxin (Stx) for STEC and elt encoding heat-labile and/or est encoding heat-stable enterotoxin (ST) for ETEC. The study investigated the genomics of STEC/ETEC hybrid strains to determine their phylogenetic position among E. coli and to define the virulence genes they harbor. METHODS: The whole genomes of three STEC/ETEC strains possessing both stx and est genes were sequenced using PacBio RS sequencer. Two of the strains were isolated from the patients, one with hemolytic uremic syndrome, and one with diarrhea. The third strain was of bovine origin. Core genome analysis of the shared chromosomal genes and comparison with E. coli and Shigella spp. reference genomes was performed to determine the phylogenetic position of the STEC/ETEC strains. In addition, a set of virulence genes and ETEC colonization factors were extracted from the genomes. The production of Stx and ST were studied. RESULTS: The human STEC/ETEC strains clustered with strains representing ETEC, STEC, enteroaggregative E. coli, and commensal and laboratory-adapted E. coli. However, the bovine STEC/ETEC strain formed a remote cluster with two STECs of bovine origin. All three STEC/ETEC strains harbored several other virulence genes, apart from stx and est, and lacked ETEC colonization factors. Two STEC/ETEC strains produced both toxins and one strain Stx only. CONCLUSIONS: This study shows that pathogroup-associated virulence genes of different E. coli can co-exist in strains originating from different phylogenetic lineages. The possibility of virulence genes to be associated with several E. coli pathogroups should be taken into account in strain typing and in epidemiological surveillance. Development of novel hybrid E. coli strains may cause a new public health risk, which challenges the traditional diagnostics of E. coli infections.


Assuntos
Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Genômica/métodos , Escherichia coli Shiga Toxigênica/isolamento & purificação , Fatores de Virulência/genética , Animais , Bovinos , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/patogenicidade , Infecções por Escherichia coli/genética , Genoma Bacteriano , Humanos , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Virulência/genética
7.
BMC Microbiol ; 15: 151, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26228572

RESUMO

BACKGROUND: This study investigated the prevalence, serotypes and antimicrobial sensitivity patterns of Salmonella enterica in environment in Ouagadougou, Burkina Faso. A total of 476 samples, consisting of 36 samples of tap water, 51 samples of well water, 87 samples of channel water, 44 samples of reservoir water, 238 samples of fish, and 20 samples of lettuce were examined using standard bacteriological procedures for Salmonella. RESULTS: Salmonella were isolated from 98 samples. Salmonella were rare in drinking water, since they were not found at all from the tap water, and only in 2 % of well water. Salmonella were more common in the water of reservoir of Tanghin (15 %), reservoir of Yamtenga (20 %), and in the water channels in the city (from 20 to 31 %). Salmonella were commonly isolated from the fish (24 %) caught from the reservoir of Tanghin and from the lettuce (50 %) irrigated with water from Tanghin. The Salmonella isolates were found to represent 50 different serotypes. The 11 most common serotypes were Salmonella Bredeney and S. Colindale (both 8.2 %), S. Muenster (6.1 %), S. Korlebu (5.1 %), S. Eastbourne and S. Poona (both 4.1 %), and S. Agona, S. Derby, S. Drac, S. Senftenberg, S. Waycross (each 3.1 %), accounting for 51.3 % of all the isolates. In general, the Salmonella strains were sensitive to the antimicrobials tested, but two strains were resistant to streptomycin and many more intermediate to streptomycin or sulphonamide. CONCLUSION: This study highlights the common prevalence of Salmonella and the high diversity of Salmonella serotypes in aquatic environment in Ouagadougou, Burkina Faso. Therefore, various human activities linked to water and consumption of water-related products, such as fish and lettuce, can lead to human Salmonella infections.


Assuntos
Peixes/microbiologia , Água Doce/microbiologia , Lactuca/microbiologia , Salmonella enterica/isolamento & purificação , Animais , Antibacterianos/farmacologia , Burkina Faso , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Prevalência , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Sorogrupo
8.
BMC Microbiol ; 15: 131, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26129826

RESUMO

BACKGROUND: Salmonella enterica spp. enterica serotype Typhimurium (STM) is the most common agent of domestically acquired salmonellosis in Finland. Subtyping methods which allow the characterization of STM are essential for effective laboratory-based STM surveillance and for recognition of outbreaks. This study describes the diversity of Finnish STM isolates using phage typing, antimicrobial susceptible testing, pulsed-field gel electrophoresis (PFGE) and multilocus variable-number tandem repeat analysis (MLVA), and compares the discriminatory power and the concordance of these methods. RESULTS: A total of 375 sporadic STM isolates were analysed. The isolates were divided into 31 definite phage (DT) types, dominated by DT1 (47 % of the isolates), U277 (9 % of the isolates) and DT104 (8 % of the isolates). Of all the isolates, 62 % were susceptible to all the 12 antimicrobials tested and 11 % were multidrug resistant. Subtyping resulted in 83 different XbaI-PFGE profiles and 111 MLVA types. The three most common XbaI-PFGE profiles (STYM1, STYM7 and STYM8) and one MLVA profile with three single locus variants accounted for 56 % and 49 % of the STM isolates, respectively. The studied isolates showed a genetic similarity of more than 70 % by XbaI-PFGE. In MLVA, 71 % of the isolates lacked STTR6 and 77 % missed STTR10p loci. Nevertheless, the calculated Simpson's diversity index for XbaI-PFGE was 0.829 (95 % CI 0.792-0.865) and for MLVA 0.867 (95 % CI 0.835-0.898). However, the discriminatory power of the 5-loci MLVA varied among the phage types. The highest concordance of the results was found between XbaI-PFGE and phage typing (adjusted Wallace coefficient was 0.833 and adjusted Rand coefficient was 0.627). CONCLUSIONS: In general, the calculated discriminatory power was higher for genotyping methods (MLVA and XbaI-PFGE) than for phenotyping methods (phage typing). Overall, comparable diversity indices were calculated for PFGE and MLVA (both DI > 0.8). However, MLVA was phage type dependent providing better discrimination of the most common phage types. Furthermore, 5-loci MLVA was a less laborious method and easier to interpret than XbaI-PFGE. Thus, the laboratory-based surveillance of the Finnish human STM infections has been conducted with a combination of phage typing, antimicrobial susceptibility testing and 5-loci MLVA since January 2014.


Assuntos
Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/análise , Infecções por Salmonella/microbiologia , Salmonella typhimurium/classificação , Tipagem de Bacteriófagos , Finlândia , Humanos , Testes de Sensibilidade Microbiana , Repetições Minissatélites , Tipagem de Sequências Multilocus , Filogenia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/isolamento & purificação
10.
J Infect Dev Ctries ; 8(10): 1334-8, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25313612

RESUMO

INTRODUCTION: Vibrio cholerae is a human pathogen and natural inhabitant of aquatic environments. In this study, we surveyed the occurrence of V. cholerae in fish harvested from a reservoir that receives discharges from the population in Ouagadougou through several channels. METHODOLOGY: A total of 238 fish and 80 water samples were analyzed for the presence of V. cholerae. RESULTS: Altogether, 13 V. cholerae strains were isolated. They were all identified as non-O1/non-O139 V. cholerae without the ctxA gene. The strains were mostly susceptible to the antimicrobials tested. CONCLUSION: Although no strains of epidemic V. cholerae serotypes were encountered, it is important to monitor the microbiological quality of this extensively used water resource and its fish.


Assuntos
Peixes/microbiologia , Vibrio cholerae/isolamento & purificação , Microbiologia da Água , Animais , Antibacterianos/farmacologia , Burkina Faso , Toxina da Cólera/genética , Genótipo , Testes de Sensibilidade Microbiana , Sorogrupo , Vibrio cholerae/classificação , Vibrio cholerae/genética
11.
PLoS One ; 9(8): e104713, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25147923

RESUMO

Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9-16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak.


Assuntos
Surtos de Doenças , Água Potável/microbiologia , Água Potável/virologia , Gastroenterite/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/classificação , Bactérias/genética , Carga Bacteriana , Criança , Pré-Escolar , Água Potável/análise , Escherichia coli/genética , Fezes/microbiologia , Feminino , Finlândia/epidemiologia , Gastroenterite/microbiologia , Gastroenterite/virologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Estudos Retrospectivos , Estações do Ano , Análise Espacial , Microbiologia da Água , Poluição da Água , Qualidade da Água , Adulto Jovem
12.
Emerg Infect Dis ; 20(7): 1214-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24960266

RESUMO

During 1993-2011, cefotaxime resistance among Salmonella enterica isolates from patients in Finland increased substantially. Most of these infections originated in Thailand; many were qnr positive and belonged to S. enterica serovar Typhimurium and S. enterica monophasic serovar 4,[5],12:i:-. Although cefotaxime-resistant salmonellae mainly originate in discrete geographic areas, they represent a global threat.


Assuntos
Cefotaxima/uso terapêutico , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Finlândia , Humanos , Tailândia , Viagem
13.
Proc Natl Acad Sci U S A ; 111(18): 6768-73, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24753568

RESUMO

The genus Yersinia has been used as a model system to study pathogen evolution. Using whole-genome sequencing of all Yersinia species, we delineate the gene complement of the whole genus and define patterns of virulence evolution. Multiple distinct ecological specializations appear to have split pathogenic strains from environmental, nonpathogenic lineages. This split demonstrates that contrary to hypotheses that all pathogenic Yersinia species share a recent common pathogenic ancestor, they have evolved independently but followed parallel evolutionary paths in acquiring the same virulence determinants as well as becoming progressively more limited metabolically. Shared virulence determinants are limited to the virulence plasmid pYV and the attachment invasion locus ail. These acquisitions, together with genomic variations in metabolic pathways, have resulted in the parallel emergence of related pathogens displaying an increasingly specialized lifestyle with a spectrum of virulence potential, an emerging theme in the evolution of other important human pathogens.


Assuntos
Evolução Molecular , Virulência/genética , Yersinia/genética , Yersinia/patogenicidade , Genoma Bacteriano , Humanos , Redes e Vias Metabólicas/genética , Filogenia , Especificidade da Espécie , Yersinia/metabolismo , Yersinia enterocolitica/genética , Yersinia enterocolitica/metabolismo , Yersinia enterocolitica/patogenicidade
14.
BMC Microbiol ; 13: 253, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24215206

RESUMO

BACKGROUND: Production and wild animals are major sources of human salmonellosis and animals raised for food also play an important role in transmission of antimicrobial resistant Salmonella strains to humans. Furthermore, in sub-Saharan Africa non-typhoidal Salmonella serotypes are common bloodstream isolates in febrile patients. Yet, little is known about the environmental reservoirs and predominant modes of transmission of these pathogens. The purpose of this study was to discover potential sources and distribution vehicles of Salmonella by isolating strains from apparently healthy slaughtered food animals and wild hedgehogs and by determining the genetic relatedness between the strains and human isolates. For this purpose, 729 feces samples from apparently healthy slaughtered cattle (n = 304), poultry (n = 350), swine (n = 50) and hedgehogs (n = 25) were examined for the presence of Salmonella enterica in Burkina Faso. The isolates were characterized by serotyping, antimicrobial-susceptibility testing, phage typing, and pulsed-field gel electrophoresis (PFGE) with XbaI and BlnI restriction enzymes. RESULTS: Of the 729 feces samples, 383 (53%) contained Salmonella, representing a total of 81 different serotypes. Salmonella was present in 52% of the cattle, 55% of the poultry, 16% of the swine and 96% of the hedgehog feces samples. Antimicrobial resistance was detected in 14% of the isolates. S. Typhimurium isolates from poultry and humans (obtained from a previous study) were multiresistant to the same antimicrobials (ampicillin, chloramphenicol, streptomycin, sulfonamides and trimethoprim), had the same phage type DT 56 and were closely related in PFGE. S. Muenster isolates from hedgehogs had similar PFGE patterns as the domestic animals. CONCLUSIONS: Based on our results it seems that production and wild animals can share the same Salmonella serotypes and potentially transmit some of them to humans. As the humans and animals often live in close vicinity in Africa and the hygiene control of the meat retail chain is defective, high Salmonella carriage rates of the animals can pose a major public health risk in Burkina Faso. This underlines the necessity for a joint and coordinated surveillance and monitoring programs for salmonellosis in Africa.


Assuntos
Portador Sadio/veterinária , Fezes/microbiologia , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella enterica/classificação , Salmonella enterica/isolamento & purificação , Animais , Tipagem de Bacteriófagos , Burkina Faso , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Bovinos , Eletroforese em Gel de Campo Pulsado , Ouriços , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem Molecular , Aves Domésticas , Prevalência , Sorotipagem , Suínos
15.
J Microbiol Methods ; 95(2): 245-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24050949

RESUMO

Yersinia pseudotuberculosis human infections caused by serotype O:1 and O:3 isolates have been common in Finland and have also caused outbreaks. Epidemiological studies on the outbreaks have been limited by the lack of accurate typing methods. During the recent years, multilocus variable-number tandem repeat analysis (MLVA) has been successfully applied for molecular typing of several bacterial pathogens. We designed an MLVA scheme based on seven loci for Y. pseudotuberculosis. The method was able to discriminate clinical isolates of serotypes O:1 and O:3 into several MLVA types. The MLVA profiles were based on the number of 6 to 9 bp long tandem repeats in each locus. The number of repeats varied from 1 to 23 depending on the locus. The loci were all located in the bacterial chromosome for stability of the markers. The MLVA method developed was serotype-specific and will be a new additional tool for the epidemiological investigations of isolates associated with disease outbreaks and for comparison of sporadic isolates.


Assuntos
Técnicas de Genotipagem/métodos , Repetições Minissatélites , Tipagem de Sequências Multilocus/métodos , Infecções por Yersinia pseudotuberculosis/epidemiologia , Yersinia pseudotuberculosis/isolamento & purificação , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Humanos , Yersinia pseudotuberculosis/classificação , Infecções por Yersinia pseudotuberculosis/microbiologia
16.
Foodborne Pathog Dis ; 10(7): 632-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23692078

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) causes diarrhea, often with severe complications. Rapid and discriminatory typing of EHEC using advanced molecular methods is needed for determination of the genetic relatedness of clones responsible for foodborne outbreaks and for finding out the transmission sources of the outbreaks. This study evaluated the potential of DiversiLab, a semiautomated repetitive sequence-based polymerase chain reaction method for the genotyping of EHEC strains. A set of 52 EHEC strains belonging to 15 O:H serotypes was clustered into 10 DiversiLab groups. All of the O157 strains and one O55 strain were classified into the same group based on a 90% similarity threshold. The other serotypes were classified to their own DiversiLab group, with the exception of one R:H(-) strain that was grouped with O5:H(-) strains. In addition, O26 and O111 strains were grouped together but ultimately subdivided according to their O-serotypes based on a 95% similarity threshold. The O104 strain, which was associated with a major outbreak of hemolytic uremic syndrome in Germany in May 2011, was also classified independently. The DiversiLab performed well in identifying isolates, but the discriminatory power of the repetitive sequence-based polymerase chain reaction method was lower than that of pulsed-field gel electrophoresis. Analysis of 15 enteropathogenic E. coli (EPEC) strains revealed that some EPEC strains clustered together with EHEC strains. Therefore, the DiversiLab system cannot be used to discriminate between these pathogroups. In conclusion, DiversiLab is a rapid and easy system for the primary exclusion of unrelated EHEC strains based on their serotypes, but more discriminatory methods, such as pulsed-field gel electrophoresis, are needed for accurate typing of the EHEC strains.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Escherichia coli Êntero-Hemorrágica/classificação , Infecções por Escherichia coli/microbiologia , Síndrome Hemolítico-Urêmica/microbiologia , Sequências Repetitivas de Ácido Nucleico/genética , Análise por Conglomerados , Impressões Digitais de DNA , DNA Bacteriano/genética , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/classificação , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Alemanha/epidemiologia , Síndrome Hemolítico-Urêmica/epidemiologia , Humanos , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Fatores de Tempo
17.
BMC Pediatr ; 13: 36, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23506294

RESUMO

BACKGROUND: Diarrhea is the most frequent health problem among children in developing countries. This study investigated the bacterial and viral etiology and related clinical and epidemiological factors in children with acute diarrhea in Ouagadougou, Burkina Faso. METHODS: Stool specimens were collected from 283 children under 5 years of age visiting hospital due to acute diarrhea and from 60 healthy controls of similar age. Pathogens were investigated by using conventional culture techniques, PCR and immunochromatographic testing. Salmonella and Shigella strains were serotyped and their susceptibility to 23 antimicrobial agents was determined by the agar dilution method. RESULTS: At least one pathogen was detected in 64% of the 283 patients and in 8% of the 60 controls (p < 0.001). Rotavirus was found in 30% of the patients, followed by diarrheagenic Escherichia coli (24%), Salmonella enterica ssp. enterica (9%), Shigella spp. (6%), adenovirus (5%) and Campylobacter spp. (2%). Multiple pathogens were found in 11% of the patients and in 2% of the controls (p = 0.028). Viruses were found mainly in children of ≤ 2 years of age, whereas bacteria were equally prevalent among all the age groups. Viral infections occurred mostly during the cool dry season and the bacterial infections during the rainy season. Fever (64%) and vomiting (61%) were the most common symptoms associated with diarrhea. Only one Salmonella strain was resistant to nalidixic acid and ciprofloxacin. Of the Shigella strains, one was resistant to nalidixic acid but 81% to trimethoprim- sulfamethoxazole, 63% to streptomycin and 50% to ampicillin. Most of all the other Salmonella and Shigella strains were sensitive to all antimicrobials tested. CONCLUSION: Rotaviruses and diarrheal E. coli were the most predominant pathogens associated with acute diarrhea in Burkinabe children. Constant antimicrobial surveillance is warranted to observe for the emergence of enteric bacteria resistant to antimicrobials that are important in treatment also of severe infections.


Assuntos
Infecções por Adenoviridae/diagnóstico , Diarreia/microbiologia , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Rotavirus/diagnóstico , Doença Aguda , Infecções por Adenoviridae/complicações , Infecções por Adenoviridae/epidemiologia , Burkina Faso , Estudos de Casos e Controles , Pré-Escolar , Diarreia/virologia , Farmacorresistência Bacteriana , Fezes/microbiologia , Fezes/virologia , Feminino , Seguimentos , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Rotavirus/complicações , Infecções por Rotavirus/epidemiologia , Salmonella/classificação , Salmonella/isolamento & purificação , Estações do Ano , Sorotipagem , Shigella/classificação , Shigella/isolamento & purificação
18.
J Water Health ; 11(1): 120-34, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23428555

RESUMO

A total of 50 Finnish bathing water samples and 34 sewage effluent samples originating from 17 locations were studied in the summers of 2006 and 2007. Campylobacter were present in 58% and adenoviruses in 12% of all bathing water samples; 53% of all sewage effluent samples were positive for Campylobacter spp. and 59% for adenoviruses. C. jejuni was the most common Campylobacter species found and human adenovirus serotype 41 was the most common identified adenovirus type. Bathing water temperature displayed a significant negative relationship with the occurrence of Campylobacter. One location had identical pulsed-field gel electrophoresis patterns of C. coli isolates in the bathing water and in sewage effluent, suggesting that sewage effluent was the source of C. coli at this bathing site. The counts of faecal indicator bacteria were not able to predict the presence of Campylobacter spp. or adenoviruses in the bathing waters. Thus the observed common presence of these pathogens in Finnish sewage effluents and bathing waters may represent a public health risk. The low water temperature in Finland may enhance the prevalence of Campylobacter in bathing waters. More attention needs to be paid to minimizing the concentrations of intestinal pathogens in bathing waters.


Assuntos
Adenoviridae/isolamento & purificação , Campylobacter/classificação , Campylobacter/isolamento & purificação , Temperatura Alta , Esgotos/microbiologia , Adenoviridae/classificação , Campylobacter/fisiologia , Enterococcus/isolamento & purificação , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Finlândia , Humanos , Lagos , Oceanos e Mares , Recreação , Natação
20.
Microbiologyopen ; 1(3): 276-84, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23170227

RESUMO

We investigated the prevalence of the virulence genes specific for five major pathogroups of diarrheagenic Escherichia coli (DEC) in primary cultures from feces of animals slaughtered for human consumption in Burkina Faso. For the study, 704 feces samples were collected from cattle (n = 304), chickens (n = 350), and pigs (n = 50) during carcass processing. The presence of the virulence-associated genes in the mixed bacterial cultures was assessed using 16-plex polymerase chain reaction (PCR). Virulence genes indicating presence of DEC were detected in 48% of the cattle, 48% of the chicken, and 68% of the pig feces samples. Virulence genes specific for different DECs were detected in the following percentages of the cattle, chicken, and pig feces samples: Shiga toxin-producing E. coli (STEC) in 37%, 6%, and 30%; enteropathogenic E. coli (EPEC) in 8%, 37%, and 32%; enterotoxigenic E. coli (ETEC) in 4%, 5%, and 18%; and enteroaggregative E. coli (EAEC) in 7%, 6%, and 32%. Enteroinvasive E. coli (EIEC) virulence genes were detected in 1% of chicken feces samples only. The study was the first of its kind in Burkina Faso and revealed the common occurrence of the diarrheal virulence genes in feces of food animals. This indicates that food animals are reservoirs of DEC that may contaminate meat because of the defective slaughter and storage conditions and pose a health risk to the consumers in Burkina Faso.

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