Healing through Music...with a Lil\u27 Bit o\u27 Southern Drawl

OBJECTIVE:Since 1987 all fecal samples referred to the clinical microbiology laboratory of the UZ Brussel were screened for the presence of Shiga toxin-producing E. coli (STEC). In this study all STEC strains isolated over a period of 27 years (1987-2014) were reexamined to achieve deeper insight in the STEC infections in our patient population. METHODS:A total of 606 STEC strains from 604 patients were subjected to molecular methods for shiga toxin (stx) subtyping, detection of additional virulence genes, typing of the O-serogroups, and phylogenetic relatedness assessment of STEC O157:H7/H-. RESULTS:Since the introduction of PCR in 1991 the annual positivity rates varied between 1.1% and 2.7%. The isolation rate of STEC O157:H7/H- remained stable over the years while the isolation rate of non-O157 serotypes increased, mainly since 2011. The majority of the patients were children. Uncomplicated- and bloody diarrhea were the most prevalent gastrointestinal manifestations (respectively 51.9% and 13.6%), 4.3% of the strains were related to the hemolytic uremic syndrome (HUS), and 30.2% of the patients showed none of these symptoms. The strains were very diverse; they belonged to 72 different O-serovars and all stx subtypes except stx1d and stx2g were identified. Out of the 23 stx2f-positives one was associated with HUS and one belonged to the E. albertii species. As seen in other studies, the frequency of strains of the O157:H7/H- serotype and strains carrying stx2a, eaeA and ehxA was higher in patients with HUS. CONCLUSIONS:The characteristics and trends of STEC infection seen in our patient population are similar to those noted in other countries. STEC infections in our hospital are mainly sporadic, and a substantial portion of the patients were asymptomatic carriers. Human STEC Stx2f infection was less rare than previously assumed and we report the first Belgian STEC stx2f HUS case and stx2f positive E. albertii infection

The benefits of whole genome sequencing for foodborne outbreak investigation from the perspective of a national reference laboratory in a smaller country

Gradually, conventional methods for foodborne pathogen typing are replaced by whole genome sequencing (WGS). Despite studies describing the overall benefits, National Reference Laboratories of smaller countries often show slower uptake of WGS, mainly because of significant investments required to generate and analyze data of a limited amount of samples. To facilitate this process and incite policy makers to support its implementation, a Shiga toxin-producing Escherichia coli (STEC) O157:H7 (stx1+, stx2+, eae+) outbreak (2012) and a STEC O157:H7 (stx2+, eae+) outbreak (2013) were retrospectively analyzed using WGS and compared with their conventional investigations. The corresponding results were obtained, with WGS delivering even more information, e.g., on virulence and antimicrobial resistance genotypes. Besides a universal, all-in-one workflow with less hands-on-time (five versus seven actual working days for WGS versus conventional), WGS-based cgMLST-typing demonstrated increased resolution. This enabled an accurate cluster definition, which remained unsolved for the 2013 outbreak, partly due to scarce epidemiological linking with the suspect source. Moreover, it allowed detecting two and one earlier circulating STEC O157:H7 (stx1+, stx2+, eae+) and STEC O157:H7 (stx2+, eae+) strains as closely related to the 2012 and 2013 outbreaks, respectively, which might have further directed epidemiological investigation initially. Although some bottlenecks concerning centralized data-sharing, sampling strategies, and perceived costs should be considered, we delivered a proof-of-concept that even in smaller countries, WGS offers benefits for outbreak investigation, if a sufficient budget is available to ensure its implementation in surveillance. Indeed, applying a database with background isolates is critical in interpreting isolate relationships to outbreaks, and leveraging the true benefit of WGS in outbreak investigation and/or prevention

Virulence of Shigatoxigenic and Enteropathogenic Escherichia coli O80:H2 in Galleria mellonella Larvae: Comparison of the Roles of the pS88 Plasmids and STX2d Phage

peer reviewedThe invasiveness properties of Shigatoxigenic and enteropathogenic Escherichia coli (STEC and EPEC) O80:H2 in humans and calves are encoded by genes located on a pS88-like ColV conjugative plasmid. The main objectives of this study in larvae of the Galleria mellonella moth were therefore to compare the virulence of eight bovine STEC and EPEC O80:H2, of two E. coli pS88 plasmid transconjugant and STX2d phage transductant K12 DH10B, of four E. coli O80:non-H2, and of the laboratory E. coli K12 DH10B strains. Thirty larvae per strain were inoculated in the last proleg with 10 μL of tenfold dilutions of each bacterial culture corresponding to 10 to 106 colony-forming units (CFUs). The larvae were kept at 37 °C and their mortality rate was followed daily for four days. The main results were that: (i) not only the STEC and EPEC O80:H2, but also different E. coli O80:non-H2 were lethal for the larvae at high concentrations (from 104 to 106 CFU) with some variation according to the strain; (ii) the Stx2d toxin and partially the pS88 plasmid were responsible for the lethality caused by the E. coli O80:H2; (iii) the virulence factors of E. coli O80:non-H2 were not identified. The general conclusions are that, although the Galleria mellonella larvae represent a useful first-line model to study the virulence of bacterial pathogens, they are more limited in identifying their actual virulence properties

Enteropathogenic Escherichia coli

peer reviewedSerogroup O80 was detected in 40% of 104 enteropathogenic Escherichia coli isolates from calves with diarrhea from 42 farms in Belgium during 2008‒2015. These isolates harbored the eae-ξ and fliCH2 genes, similar to the O80 attaching-effacing Shigatoxigenic E. coli isolates found in humans in France. This strain might be emerging

Distribution of the detected virulence genes.

<p>Distribution of the detected virulence genes.</p

Distribution of the <i>stx</i>-subtypes.

<p>Distribution of the <i>stx</i>-subtypes.</p

Characteristics of the 23 strains isolated from HUS patients.

<p>Characteristics of the 23 strains isolated from HUS patients.</p

Annual number of STEC isolates (a), annual STEC isolation rate 1991–2014 (b) (---series lines), and annual STEC positivity rate 2008–2014 (c) (---linear trend line).

<p>Annual number of STEC isolates (a), annual STEC isolation rate 1991–2014 (b) (---series lines), and annual STEC positivity rate 2008–2014 (c) (---linear trend line).</p

O-serogroups isolated in the present study: Classification in seropathotypes and association with HUS of STEC.

<p>O-serogroups isolated in the present study: Classification in seropathotypes and association with HUS of STEC.</p

Low prevalence of the 'gang of seven' and absence of the O80:H2 serotypes among Shigatoxigenic and enteropathogenic Escherichia coli (STEC and EPEC) in intestinal contents of healthy cattle at two slaughterhouses in Belgium in 2014.

The purpose of this survey was to estimate the respective prevalence of the 'gang of seven' and 'non-gang of seven' serotypes of Shigatoxigenic and enteropathogenic Escherichia coli and to identify the O80:H2 serotype in 245 intestinal contents collected at two slaughterhouses in Belgium in 2014