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West Jerusalem, Israel

Halperin T.,Israel Defense Forces | Levine H.,Hebrew University of Jerusalem | Korenman Z.,Government Central Laboratories | Burstein S.,Israel Defense Forces | And 3 more authors.
European Journal of Clinical Microbiology and Infectious Diseases | Year: 2016

Beta-hemolytic group G streptococci (GGS) are increasingly recognized as a source of substantial morbidity, causing mild to severe sporadic infections as well as outbreaks. The purpose of this study was to determine the genetic diversity and antibiotic resistance of GGS in Israel in order to aid in prevention and control. A total of 325 GGS isolates were collected in Israel between 2007 and 2011 from three determined settings: (1) carriage (n = 60), an observational longitudinal carriage study in the IF, (2) non-invasive (n = 166), clinical sporadic and epidemic non-invasive cases in the IDF, and (3) invasive (n = 99) cases of bacteremia collected during this period in Israel from a similar age group, at the national Streptococcal Reference Center. All isolates were characterized genetically and by their antibiotic-resistance profile. emm typing revealed 35 distinct types and subtypes among 228 S. dysgalactiae subsp. equisimilis (SDSE) isolates, with high genetic diversity. An additional 97 GGS were identified as Streptococcus anginosus (SAG). The proportion of SDSE was higher in the invasive (100 %) and non-invasive (63.8 %) isolates compared to the carriage ones (38.3 %). Clindamycin, erythromycin, azithromycin and tetracycline resistance was detected in 6.6 %, 8.6 %, 9.7 % and 37.6 % of isolates, respectively. Overall, the most resistant isolates were in the invasive group and the fewest were in the SAG group. Considerable genetic diversity and common antibiotic resistance were revealed among GGS strains which differed according to the epidemiologic settings. Further clinical, epidemiological and basic research of GGS as a pathogen is warranted. © 2016 Springer-Verlag Berlin Heidelberg Source

Biber A.,Tel Aviv University | Biber A.,The Gertner Institute for Epidemiology and Health Policy Research | Abuelaish I.,University of Toronto | Rahav G.,Tel Aviv University | And 10 more authors.
PLoS ONE | Year: 2012

Epidemiological data on community acquired methicillin-resistant-Staphylococcus aureus (CA-MRSA) carriage and infection in the Middle-East region is scarce with only few reports in the Israeli and Palestinian populations. As part of a Palestinian-Israeli collaborative research, we have conducted a cross-sectional survey of nasal S. aureus carriage in healthy children and their parents throughout the Gaza strip. Isolates were characterized for antibiotic susceptibility, mec gene presence, PFGE, spa type, SCCmec-type, presence of PVL genes and multi-locus-sequence-type (MLST). S. aureus was carried by 28.4% of the 379 screened children-parents pairs. MRSA was detected in 45% of S. aureus isolates, that is, in 12% of the study population. A single ST22-MRSA-IVa, spa t223, PVL-gene negative strain was detected in 64% of MRSA isolates. This strain is typically susceptible to all non-β-lactam antibiotics tested. The only predictor for MRSA carriage in children was having an MRSA carrier-parent (OR = 25.5, P = 0.0004). Carriage of the Gaza strain was not associated with prior hospitalization. The Gaza strain was closely related genetically to a local MSSA spa t223 strain and less so to EMRSA15, one of the pandemic hospital-acquired-MRSA clones, scarcely reported in the community. The rapid spread in the community may be due to population determinants or due to yet unknown advantageous features of this particular strain. © 2012 Biber et al. Source

Gal-Mor O.,Infectious Diseases Research Laboratory | Suez J.,Infectious Diseases Research Laboratory | Suez J.,Tel Aviv University | Elhadad D.,Infectious Diseases Research Laboratory | And 8 more authors.
Clinical and Vaccine Immunology | Year: 2012

Enteric fever is an invasive life-threatening systemic disease caused by the Salmonella enterica human-adapted serovars Typhi and Paratyphi. Increasing incidence of infections with Salmonella enterica serovar Paratyphi A and the spreading of its antibiotic-resistant derivates pose a significant health concern in some areas of the world. Herein, we describe a molecular and phenotypic characterization of an S. Paratyphi A strain accounted for a recent paratyphoid outbreak in Nepal that affected at least 37 travelers. Pulsed-field gel electrophoresis analysis of the outbreak isolates revealed one genetic clone (pulsotype), confirming a single infecting source. Genetic profiling of the outbreak strain demonstrated the contribution of specific bacteriophages as a prime source of genetic diversity among clinical isolates of S. Paratyphi A. Phenotypic characterization in comparison with the S. Paratyphi A ATCC 9150 reference sequenced strain showed differences in flagellar morphology and increased abilities of the outbreak strain with respect to its motility, invasion into nonphagocytic cells, intracellular multiplication, survival within macrophages, and higher induction of interleukin-8 (IL-8) secreted by host cells. Collectively, these differences suggest an enhanced virulence potential of this strain and demonstrate an interesting phenotypic variation among S. Paratyphi A isolates. In vivo profiling of 16 inflammatory cytokines in patients infected with the outbreak strain revealed a common profile of a remarkable gamma interferon (IFN-γ) induction together with elevated concentrations of tumor necrosis factor alpha (TNF-α), IL-6, IL-8, IL-10, and IL-15, but not IL-12, which was previously demonstrated as elevated in nontyphoidal Salmonella infections. This apparent profile implies a distinct immune response to paratyphoid infections. Copyright © 2012, American Society for Microbiology. All Rights Reserved. Source

Broza Y.Y.,Technion - Israel Institute of Technology | Raz N.,Technion - Israel Institute of Technology | Lerner L.,Government Central Laboratories | Danin-Poleg Y.,Technion - Israel Institute of Technology | Kashi Y.,Technion - Israel Institute of Technology
International Journal of Food Microbiology | Year: 2012

The biotype 3 group of the human pathogen Vibrio vulnificus emerged in Israel probably as a result of genome hybridization of two bacterial populations. We performed a genomic and phylogenetic study of V. vulnificus strains isolated from the environmental niche from which this group emerged - fish aquaculture in Israel. The genetic relationships and evolutionary aspects of 188 environmental and clinical isolates of the bacterium were studied by genomic typing. Genetic relations were determined based on variation at 12 variable number tandem repeat (VNTR, also termed SSR) loci. Analysis revealed a new cluster, in addition to the main groups of biotype 1& 2 and biotype 3. Similar grouping results were obtained with three different statistical approaches. Isolates forming this new cluster presented unclear biochemical profile nevertheless were not identified as biotype 1 or biotype 3. Further examination of representative strains by multilocus sequence typing (MLST) of 10 housekeeping genes and 5 conserved hypothetical genes supported the identification of this as yet undiscovered phylogroup (phenotypically diverse), termed clade A herein. This new clonal subgroup includes environmental as well as clinical isolates. The results highlight the fish aquaculture environment, and possibly man-made ecological niches as a whole, as a source for the emergence of new pathogenic strains. © 2011 Elsevier B.V. Source

Zaidenstein R.,Infectious Diseases Unit | Peretz C.,Tel Aviv University | Nissan I.,Government Central Laboratories | Reisfeld A.,Government Central Laboratories | And 4 more authors.
European Journal of Clinical Microbiology and Infectious Diseases | Year: 2010

Extraintestinal disease occurs in 5-8% of non-typhoid Salmonella enterica (NTS) infections and is more likely to be associated with hospitalization and death. The study examined the epidemiology of extraintestinal NTS infections in Israel and the possible effects of patients' age and sex. NTS isolates passively submitted to the National Salmonella Reference Center during 1996-2006 were the source for the study cohort. Poisson regression models were used to assess incidence trends over the study years and to evaluate the effects of patients' age and sex on the incidence of extraintestinal NTS manifestations. A total of 36,822 stool and 1,415 (3.7%) patient-unique NTS isolates from blood (74.1%), urine (18.3%), and other sources (3.7%) were studied. Serotypes Enteritidis, Virchow, and Typhimurium accounted for 66.3% of the isolates. Analysis showed a highly significant quadratic (U-shaped) relationship between patients' age and the incidence of extraintestinal isolation (p < 0.001), with increasing risk in the two extremes of age. Differences between the incidence of blood and urine sources were significant in patients <10 and ≥60 years old (relative risk [RR] = 5.88, 95% confidence interval [CI] 3.36-10.30, p < 0.001 and RR = 1.66, 95% CI 1.09-2.53, p = 0.017, respectively). Males ≥60 years of age were more likely than females of the same age to have bacteremia (RR = 1.90, 95% CI 1.39-2.61, p > 0.001) and less likely to have urinary NTS isolation (RR = 0.50, 95% CI 0.28-0.89, p = 0.018). Serotype Virchow had the highest incidence in patients <10 years of age, while serotype Enteritidis had the highest incidence in patients ≥60 years old. The study revealed a complex effect of patients' age and sex on the epidemiology of extraintestinal NTS manifestations. © 2010 Springer-Verlag. Source

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