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Raphael, B. H.

Publications and source records attributed to Raphael, B. H..

3 recordsLinked to original sources

Global emergence and dissemination of Neisseria gonorrhoeae ST-9363 isolates with reduced susceptibility to azithromycin

Neisseria gonorrhoeae multi-locus sequence type (ST) 9363 genogroup isolates have been associated with reduced azithromycin susceptibility (AZMrs) and show evidence of clonal expansion in the U.S. Here we analyze a global collection of ST-9363 genogroup genomes to shed light on the emergence and dissemination of this strain. The global population structure of ST-9363 genogroup falls into three lineages: Basal, European, and North American; with 32 clades within all lineages. Although, ST-9363 genogroup is inferred to have originated from Asia in the mid-19th century; we estimate the three modern lineages emerged from Europe in the late 1970s to early 1980s. The European lineage appears to have emerged and expanded from around 1986 to 1998, spreading into North America and Oceania in the mid-2000s with multiple introductions, along with multiple secondary reintroductions into Europe. Our results suggest two separate acquisition events of mosaic mtrR and mtrR promoter alleles: first during 2009-2011 and again during the 2012-2013 time, facilitating the clonal expansion of this genogroup with AZMrs in the U.S. By tracking phylodynamic evolutionary trajectories of clades that share distinct demography as well as population-based genomic statistics, we demonstrate how recombination and selective pressures in the mtrCDE efflux operon granted a fitness advantage to establish ST-9363 as a successful gonococcal lineage in the U.S. and elsewhere. Although it is difficult to pinpoint the exact timing and emergence of this young genogroup, it remains critically important to continue monitoring it, as it could acquire additional resistance markers.

microbiology

Whole-Genome Enrichment and Sequencing of Chlamydia trachomatis Directly from Patient Clinical Vaginal and Rectal Swabs

Chlamydia trachomatis is the most prevalent cause of bacterial sexually transmitted infections (STIs) worldwide. U.S. cases have been steadily increasing for more than a decade in both the urogenital tract and rectum. C. trachomatis is an obligate intracellular bacterium that is not easily cultured, limiting the capacity for genome studies to understand strain diversity and emergence among various patient populations globally. While Agilent SureSelectXT target-enrichment RNA bait libraries have been developed for whole-genome enrichment and sequencing of C. trachomatis directly from clinical urine, vaginal, conjunctival and rectal samples, efficiencies are only 60-80% for [≥]95-100% genome coverage. We therefore re-designed and expanded the RNA bait library to augment enrichment of the organism from clinical samples to improve efficiency. We describe the expanded library, the limit of detection for C. trachomatis genome copy input, and the 100% efficiency and high-resolution of generated genomes where genomic recombination among paired vaginal and rectal specimens from four patients was identified. This workflow provides a robust approach for discerning genomic diversity and advancing our understanding of the molecular epidemiology of contemporary C. trachomatis STIs across sample types, among geographic populations, sexual networks, and outbreaks associated with proctitis/proctocolitis among women and men who have sex with men. ImportanceChlamydia trachomatis is an obligate intracellular bacterium that is not easily cultured, and there is limited information on rectal C. trachomatis transmission and its impact on morbidity. To improve efficiency of previous studies involving whole genome target enrichment and sequencing of C. trachomatis directly from clinical urine, vaginal, conjunctival, and rectal specimens, we expanded the RNA bait library to augment enrichment of the organism from clinical samples. We demonstrate an increased efficiency in the percentage of reads mapping to C. trachomatis. We show the new system is sensitive for near identical genomes of C. trachomatis from two body sites in four women. Further, we provide a robust genomic epidemiologic approach to advance our understanding of C. trachomatis strains causing ocular, urogenital and rectal infections, and to explore geo-sexual networks, outbreaks of colorectal infections among women and men who have sex with men, and the role of these strains in morbidity.

genomics

A community-driven resource for genomic surveillance of Neisseria gonorrhoeae at Pathogenwatch

BackgroundAntimicrobial resistant (AMR) Neisseria gonorrhoeae is an urgent threat to public health, as strains resistant to at least one of the two last line antibiotics used in empiric therapy of gonorrhoea, ceftriaxone and azithromycin, have spread internationally. Whole genome sequencing (WGS) data can be used to identify new AMR clones, transmission networks and inform the development of point-of-care tests for antimicrobial susceptibility, novel antimicrobials and vaccines. Community driven tools that provide an easy access to and analysis of genomic and epidemiological data is the way forward for public health surveillance. MethodsHere we present a public health focussed scheme for genomic epidemiology of N. gonorrhoeae at Pathogenwatch (https://pathogen.watch/ngonorrhoeae). An international advisory group of experts in epidemiology, public health, genetics and genomics of N. gonorrhoeae was convened to inform on the utility of current and future analytics in the platform. We implement backwards compatibility with MLST, NG-MAST and NG-STAR typing schemes as well as an exhaustive library of genetic AMR determinants linked to a genotypic prediction of resistance to eight antibiotics. A collection of over 12,000 N. gonorrhoeae genome sequences from public archives has been quality-checked, assembled and made public together with available metadata for contextualization. ResultsAMR prediction from genome data revealed specificity values over 99% for azithromycin, ciprofloxacin and ceftriaxone and sensitivity values around 99% for benzylpenicillin and tetracycline. A case study using the Pathogenwatch collection of N. gonorrhoeae public genomes showed the global expansion of an azithromycin resistant lineage carrying a mosaic mtr over at least the last 10 years, emphasizing the power of Pathogenwatch to explore and evaluate genomic epidemiology questions of public health concern. ConclusionsThe N. gonorrhoeae scheme in Pathogenwatch provides customized bioinformatic pipelines guided by expert opinion that can be adapted to public health agencies and departments with little expertise in bioinformatics and lower resourced settings with internet connection but limited computational infrastructure. The advisory group will assess and identify ongoing public health needs in the field of gonorrhoea, particularly regarding gonococcal AMR, in order to further enhance utility with modified or new analytic methods.

genomics