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Ljubljana, Slovenia

Silva R.O.S.,Federal University of Minas Gerais | Rupnik M.,University of Maribor | Rupnik M.,National Laboratory for Health | Diniz A.N.,Federal University of Minas Gerais | And 2 more authors.
Memorias do Instituto Oswaldo Cruz | Year: 2015

Clostridium difficile is an emerging enteropathogen responsible for pseudomembranous colitis in humans and diarrhea in several domestic and wild animal species. Despite its known importance, there are few studies about C. difficile polymerase chain reaction (PCR) ribotypes in Brazil and the actual knowledge is restricted to studies on human isolates. The aim of the study was therefore to compare C. difficile ribotypes isolated from humans and animals in Brazil. Seventysix C. difficile strains isolated from humans (n = 25), dogs (n = 23), piglets (n = 12), foals (n = 7), calves (n = 7), one cat, and one manned wolf were distributed into 24 different PCR ribotypes. Among toxigenic strains, PCR ribotypes 014/020 and 106 were the most common, accounting for 14 (18.4%) and eight (10.5%) samples, respectively. Fourteen different PCR ribotypes were detected among human isolates, nine of them have also been identified in at least one animal species. PCR ribotype 027 was not detected, whereas 078 were found only in foals. This data suggests a high diversity of PCR ribotypes in humans and animals in Brazil and support the discussion of C. difficile as a zoonotic pathogen © 2015, Fundacao Oswaldo Cruz. All rights reserved. Source

Krt Lah A.,Health Care Center Gorenja Vas | Frelih T.,National Institute of Public Health | Kosnik I.G.,National Laboratory for Health
Zdravstveno Varstvo | Year: 2015

Background. An outbreak of gastroenteritis of etiologically unspecified origin and an outbreak of Salmonellosis occurred simultaneously in September 2011 in Tržič. The purpose of the investigation of both outbreaks was to identify the most probable source and the mode of transmission and to implement preventive measures. Methods. In two retrospective case-control studies, the association between gastroenteritis of etiologically unspecified origin or Salmonellosis and food from a restaurant or drinking tap water were tested by univariate and multivariate analysis. The subject in the first study was a sick person with salmonellosis, and the subject in the second study was a resident that developed diarrhoea and/ or vomiting. Cases were reported by doctors, and controls were selected from healthy persons who responded to the questionnaire. Results. A person exposed to food from the restaurant had a 24.8 times higher odds ratio (univariate analysis OR 24.8, 95% CI 7.5 to 82.3, p <0.05; multivariate analysis OR 14.7, 95% CI 3.5-61.3, p <0.05) for salmonellosis than non-exposed. A resident exposed to tap water from specific water source had a 3.4 times higher odds ratio (univariate analysis of OR 3.4, 95% CI 2.2 to 5.1 is p <0.05, multivariate analysis of RO 2.9, 95% CI 1, 7 to 5.3, p <0.05), for gastroenteritis of unspecific etiology than non-exposed. The dose response relationship was also statistically significant. Conclusion. Analytical cases - controls studies confirmed a causal relationship between salmonellosis and food from the specific restaurant and the causal relationship between gastroenteritis of etiologically unspecified origin and drinking tap water from specific water source. Salmonella enteritidis may have entered into the restaurant through tap water. © 2015, Versita. All rights reserved. Source

Janezic S.,National Laboratory for Health | Indra A.,Austrian Agency for Health and Food Safety AGES | Rattei T.,University of Vienna | Weinmaier T.,University of Vienna | And 2 more authors.
PLoS ONE | Year: 2014

PCR-ribotyping, a typing method based on size variation in 16S-23S rRNA intergenic spacer region (ISR), has been used widely for molecular epidemiological investigations of C. difficile infections. In the present study, we describe the sequence diversity of ISRs from 43 C. difficile strains, representing different PCR-ribotypes and suggest homologous recombination as a possible mechanism driving the evolution of 16S-23S rRNA ISRs. ISRs of 45 different lengths (ranging from 185 bp to 564 bp) were found among 458 ISRs. All ISRs could be described with one of the 22 different structural groups defined by the presence or absence of different sequence modules; tRNAAla genes and different combinations of spacers of different lengths (33 bp, 53 bp or 20 bp) and 9 bp direct repeats separating the spacers. The ISR structural group, in most cases, coincided with the sequence length. ISRs that were of the same lengths had also very similar nucleotide sequence, suggesting that ISRs were not suitable for discriminating between different strains based only on the ISR sequence. Despite large variations in the length, the alignment of ISR sequences, based on the primary sequence and secondary structure information, revealed many conserved regions which were mainly involved in maturation of pre-rRNA. Phylogenetic analysis of the ISR alignment yielded strong evidence for intra- and inter-homologous recombination which could be one of the mechanisms driving the evolution of C. difficile 16S-23S ISRs. The modular structure of the ISR, the high sequence similarities of ISRs of the same sizes and the presence of homologous recombination also suggest that different copies of C. difficile 16S-23S rRNA ISR are evolving in concert. © 2014 Janezic et al. Source

Janezic S.,National Laboratory for Health | Rupnik M.,National Laboratory for Health | Rupnik M.,University of Maribor
Research in Microbiology | Year: 2015

Approaches to exploring Clostridium difficile genomic diversity have ranged from molecular typing methods to use of comparative genome microarrays and whole genome sequence comparisons. The C. difficile population structure is clonal and distributed into six clades, which correlate well with MLST STs (multilocus sequence types) and PCR ribotypes. However, toxigenic strains and strains with increased virulence are distributed throughout several clades. Here we summarize studies on C. difficile genomic diversity, with emphasis on phylogenetic aspects, epidemiological aspect and variability of some virulence factors. © 2015 Institut Pasteur. Source

Janezic S.,National Laboratory for Health | Zidaric V.,National Laboratory for Health | Pardon B.,Ghent University | Indra A.,Austrian Agency for Health and Food Safety AGES | And 14 more authors.
BMC Microbiology | Year: 2014

Background: Clostridium difficile is an important cause of intestinal infections in some animal species and animals might be a reservoir for community associated human infections. Here we describe a collection of animal associated C. difficile strains from 12 countries based on inclusion criteria of one strain (PCR ribotype) per animal species per laboratory. Results: Altogether 112 isolates were collected and distributed into 38 PCR ribotypes with agarose based approach and 50 PCR ribotypes with sequencer based approach. Four PCR ribotypes were most prevalent in terms of number of isolates as well as in terms of number of different host species: 078 (14.3% of isolates; 4 hosts), 014/020 (11.6%; 8 hosts); 002 (5.4%; 4 hosts) and 012 (5.4%; 5 hosts). Two animal hosts were best represented; cattle with 31 isolates (20 PCR ribotypes; 7 countries) and pigs with 31 isolates (16 PCR ribotypes; 10 countries). Conclusions: This results show that although PCR ribotype 078 is often reported as the major animal C. difficile type, especially in pigs, the variability of strains in pigs and other animal hosts is substantial. Most common human PCR ribotypes (014/020 and 002) are also among most prevalent animal associated C. difficile strains worldwide. The widespread dissemination of toxigenic C. difficile and the considerable overlap in strain distribution between species furthers concerns about interspecies, including zoonotic, transmission of this critically important pathogen. © 2014 Janezic et al.; licensee BioMed Central Ltd. Source

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