Yersinia enterocolitica strains associated with human infections in Switzerland 2001-2010

Yersinia enterocolitica infections are common in humans. However, very scarce data are available on the different biotypes and virulence factors of human strains, which has proved to be problematic to assess the clinical significance of the isolated strains. In this study, the presence of the ail gene and distribution of different bio- and serotypes among human Y. enterocolitica strains and their possible relation to the genotype and antimicrobial resistance were studied. In total, 128 Y. enterocolitica strains isolated from human clinical samples in Switzerland during 2001-2010 were characterised. Most (75 out of 128) of the Y. enterocolitica strains belonged to biotypes 2, 3 or 4 and carried the ail gene. One of the 51 strains that belonged to biotype 1A was also ail positive. Most of the ail-positive strains belonged to bioserotype 4/O:3 (47 out of 76) followed by 2/O:9 (22 out of 76). Strains of bioserotype 4/O:3 were dominant among patients between 20 and 40years old and strains of biotype 1A dominate in patients over 40years. Strains belonging to biotypes 2, 3 and 4, which all carried the ail gene, exhibited a high homogeneity with PFGE typing. Y. enterocolitica 2/O:5,27 and 2/O:9 strains showed resistance to amoxicillin/clavulanic acid and cefoxitin, but Y. enterocolitica 4/O:3 strains did no

Antimicrobial resistance patterns and genotypes of Salmonella enterica serovar Hadar strains associated with human infections in Switzerland, 2005-2010

Salmonella Hadar ranks in the top ten serovars reported from humans in Switzerland. In this study, all 64 S. Hadar strains isolated from different patients from 2005 to 2010 in Switzerland were characterized by (i) assessing phenotypic antimicrobial resistance profiles using the disk diffusion method and (ii) by genotyping using pulsed-field gel electrophoresis (PFGE) in order to evaluate the relationship of the strains. The annual incidences varied between 0·32/100000 in 2005 (highest incidence) and 0·065/100000 in 2007 (lowest incidence). In total 71·8% of the isolates were resistant to nalidixic acid. Although 40·6% of the strains were resistant to the β-lactam antibiotic ampicillin, they remained susceptible to the third-generation cephalosporin cefotaxime. Genotyping revealed a primary cluster consisting of 42 strains, sharing a similarity of >92%, with a subcluster of 18 strains with indistinguishable patterns. Resistance profiles allowed further differentiation within this subcluster providing a link of two strains to an outbreak in Spai

Shiga toxin-producing Escherichia coli O157 associated with human infections in Switzerland, 2000-2009

Shiga toxin-producing Escherichia coli (STEC), an important foodborne pathogen, can cause mild to severe bloody diarrhoea (BD), sometimes followed by life-threatening complications such as haemolytic uraemic syndrome (HUS). A total of 44 O157 strains isolated from different patients from 2000 through 2009 in Switzerland were further characterized and linked to medical history data. Non-bloody diarrhoea was experienced by 15·9%, BD by 61·4% of the patients, and 29·5% developed HUS. All strains belonged to MLST type 11, were positive for stx2 variants (stx2 and/or stx2c), eae and ehxA, and only two strains showed antibiotic resistance. Of the 44 strains, nine phage types (PTs) were detected the most frequent being PT32 (43·2%) and PT8 (18·2%). By PFGE, 39 different patterns were found. This high genetic diversity within the strains leads to the conclusion that STEC O157 infections in Switzerland most often occur as sporadic case

Searching for magnetic monopoles trapped in accelerator material at the Large Hadron Collider

If produced in high energy particle collisions at the LHC, magnetic monopoles could stop in material surrounding the interaction points. Obsolete parts of the beam pipe near the CMS interaction region, which were exposed to the products of pp and heavy ion collisions, were analysed using a SQUID-based magnetometer. The purpose of this work is to quantify the performance of the magnetometer in the context of a monopole search using a small set of samples of accelerator material ahead of the 2013 shutdown.Comment: 11 page

Diarrheagenic enteroaggregative Escherichia coli causing urinary tract infection and bacteremia leading to sepsis

We report a case of a 55-year-old immunocompromised female who presented to the emergency department with severe diarrhea and vomiting following travel to the Philippines. Stool bacteriology revealed a mixed infection involving an enteropathogenic Escherichia coli and two distinct strains of enteroaggregative Escherichia coli (EAEC). During hospitalization, urine and blood culture tested positive for one of the diarrheagenic EAEC strains, necessitating urinary catheterization, intensive care, and antimicrobial treatment with trimethoprim-sulfamethoxazole, followed by meropenem. Although known to occasionally cause urinary tract infections, EAEC have not been previously associated with sepsis. Our report highlights the potential of EAEC to cause severe extraintestinal infections

Salmonella enterica serotype Virchow associated with human infections in Switzerland: 2004-2009

BACKGROUND: Salmonellosis is one of the most important foodborne diseases and a major threat to public health. Salmonella serotype Virchow ranks among the top five serovars in Europe. METHOD: A total of 153 strains isolated from different patients from 2004 through 2009 in Switzerland were further characterized by (i) assessing phenotypic antibiotic resistance profiles using the disk diffusion method and (ii) by genotyping using pulsed-field gel electrophoresis (PFGE) after macrorestriction with XbaI in order to evaluate strain relationship. RESULTS: The relative frequency of S. Virchow among other Salmonella serovars varied between 4th to 8th rank. The annual incidence ranged from 0.45/100'000 in 2004 to 0.40/100'000 in 2009. A total of 48 strains (32%) were resistant to one to 3 antimicrobials, 54 strains (36%) displayed resistance patterns to more than three antibiotics. No trend was identifiable over the years 2004 to 2009. We found a high prevalence (62%) of nalidixic acid resistant strains, suggesting an equally high rate of decreased fluoroqionolone susceptibility, whereas intermediate resistance to ciprofloxacin was negligible. Two strains were extended spectrum β-lactamase (ESBL) producers. Analysis of PFGE patterns uncovered a predominant cluster (similarity coefficient above 80%) consisting of 104 of the 153 strains. CONCLUSION: The worldwide increase of antibiotic resistances in Salmonella is an emerging public health problem. For Switzerland, no clear trend is identifiable over the years 2004 to 2009 for S. Virchow. Antimicrobial susceptibility and resistance profiles varied considerably within this period. Nevertheless, the situation in Switzerland coincided with findings in other European countries. Genotyping results of this strain collection revealed no evidence for an undetected outbreak within this time period

Outbreak of Salmonella enterica serovar Typhimurium in Switzerland, May – June 2008, implications for production and control of meat preparations

An increased number of Salmonella Typhimurium cases were reported in Switzerland between May and June 2008. Investigations involved 72 cases. Results of PFGE typing identified several outbreak strains, the dominating one present in 43 of the 72 isolates. Strains affecting one third of the cases were also found in animal samples, in particular pork. However, no specific food source could be identified. Outbreaks described in this paper highlight the importance of food safety regulations such as those on minced meat and meat preparations issued by the European Commission and adopted by Switzerland into the national law