Epidemiology of extended-spectrum β-lactamase-producing Escherichia coli in Sweden 2007–2011

Abstract

Extended-spectrum β-lactamase (ESBL) -producing Enterobacteriaceae have been notifiable according to the Swedish Communicable Disease Act since 2007. A major increase in the number of cases has been observed, with 2099 cases in 2007 and 7225 cases in 2012. The majority of the isolates are Escherichia coli. Additionally, Swedish data on the prevalence of ESBL-producing invasive isolates of E. coli are available through EARS-Net, and through biannual point prevalence studies, where molecular characterization of isolates from the entire country is carried out. This paper describes major trends in the Swedish epidemiology of ESBL-producing E. coli in the period 2007-2012. Isolates from the point prevalence studies were subjected to antimicrobial susceptibility testing, ESBL genotyping, pulsed-field gel electrophoresis, multi-locus sequence typing and phylogenetic grouping with PCR. The distribution of sequence types, resistance genes and susceptibility levels were all stable over the three study periods. The dominating resistance gene conferring ESBL was blaCTX -M-15 , found in 54-58% of the isolates. ST131 represented 34-38% of the isolates. Other major sequence types were ST38, ST69, ST405, ST617 and ST648, each representing 2-6% of the isolates. Phylogenetic group B2 was the most common, and was observed in 41-47% of the isolates. However, among ST131 isolates the B2 phylogenetic group represented 90-98% of the isolates. The most important epidemiological difference seen over time was that the median age of infected women decreased from 62 to 52 years (p <0.0001) and infected men from 67 to 64 years. A potential explanation might be the shift towards a higher proportion of community-acquired infections in individuals lacking comorbidities.

Regional distribution of nosocomial infections due to ESBL-positive Enterobacteriaceae in Germany: data from the German National Reference Center for the Surveillance of Nosocomial Infections (KISS)

“…Our results also support the finding that infections due to Gram-negative bacteria are less likely to occur in colder seasons [17]. Our data confirm several studies on infections due to ESBLpositive bacteria that show a trend towards infections in younger patients below 70 years [18,19].…”

Antibiotic Susceptibilities and Genetic Characteristics of Extended-Spectrum Beta-Lactamase-Producing <i>Escherichia coli</i> Isolates from Stools of Pediatric Diarrhea Patients in Surabaya, Indonesia

“…The CTX-M-15-type ESBL-producing E. coli ST131 clone has spread across many regions of the world (28)(29)(30)(31). Our data showed that the CTX-M-15-type comprised 84 of the strains, including some strains with a combination CTX-M-15 and TEM-1 or SHV-7.…”

“…ESBL-producing strain ST617 has also spread worldwide (28,29,39,40) and can be found, for instance, in Belgium, Sweden, Nigeria, and France. Our MLST data showed that, although 24 of the ESBL-producing strains were non-typable, ST617 was commonly found in our ESBL isolates, as in the aforementioned studies; ST617 strains had higher resistance to most of the antibiotics tested in this study, except IPM, AMK, and FOM.…”

Evaluation of a Method Using Three Genomic Guided Escherichia coli Markers for Phylogenetic Typing of E. coli Isolates of Various Genetic Backgrounds

“…In addition to the ST131 strain, an E. coli D-ST405 isolate and a B2-ST95 isolate were also identified in this study. E. coli D-ST405 has frequently been reported as one of the ESBL-producing E. coli clones in many countries, particularly in Japan (27)(28)(29)(30)(31)(32)(33)(34)(35). Another E. coli isolate, B2-ST95, was reported as an extraintestinal pathogenic E. coli strain exhibiting high virulence, which potentially originated from poultry (36).…”