scholarly journals Increasing azithromycin resistance in Neisseria gonorrhoeae due to NG-MAST 12302 clonal spread in Canada, 2015-2018

Author(s):  
Pam Sawatzky ◽  
Walter Demczuk ◽  
Brigitte Lefebvre ◽  
Vanessa Allen ◽  
Mathew Diggle ◽  
...  

Objectives: Azithromycin resistant (AZIR) gonorrhea has been steadily increasing in Canada over the past decade which is cause for alarm as azithromycin (AZI) has been part of the combination therapy recommended by the Canadian Guidelines on Sexually Transmitted Infections (CGSTI) since 2012. Method: Neisseria gonorrhoeae (NG) with AZI MICs ≥ 1 mg/L collected between 2015 and 2018 as part of the Gonococcal Antimicrobial Surveillance Program-Canada underwent antimicrobial susceptibility testing, molecular typing and whole genome sequencing. Regional, demographic and clinical isolation site comparisons were made to aid in our understanding of AZI susceptibility trending. Results: 3,447 NG with AZI MICs ≥ 1 mg/L were identified in Canada, increasing from 6.3% in 2015 to 26.5% of isolates in 2018. Central Canada had the highest proportion rising from 9.2% in 2015 to 31.2% in 2018. 273 different NG-MAST sequence types were identified among these isolates with ST-12302 the most prevalent (50.9%). Whole genome sequencing identified the Neisseria lactamica -like mosaic mtr locus as the mechanism of AZIR in isolates of ST-12302 and isolates genetically similar (differ by ≤ 5 base pairs) designated as the ST-12302 genogroup, accounting for 65.2% of study isolateswhich were originally identified in central Canada but spread to other regions by 2018. Conclusion: Genomic analysis indicated that AZIR in Canadian NG expanded rapidly due to clonal spread of the ST-12302 genogroup. The rapid expansion of this AZIR clonal group in all regions of Canada is of concern. CGSTI are currently under review to address the increase in AZIR in Canada.

2020 ◽  
Vol 64 (9) ◽  
Author(s):  
Nidhi R. Parmar ◽  
Reema Singh ◽  
Irene Martin ◽  
Sumudu R. Perera ◽  
Walter Demczuk ◽  
...  

ABSTRACT Whole-genome sequencing was used to identify mutations in antibiotic resistance-conferring genes to compare susceptibility predictions with MICs and to ascertain strain types in 99 isolates of Neisseria gonorrhoeae. Genotypes associated with susceptibility, as well as MIC creep or emerging resistance, were noted. Phylogenomic analysis revealed three distinctive clades and putative gonococcal transmission linkages involving a tetracycline-resistant N. gonorrhoeae outbreak and the clonal spread of susceptible isolates in men.


2020 ◽  
Vol 58 (4) ◽  
Author(s):  
Ellen N. Kersh ◽  
Cau D. Pham ◽  
John R. Papp ◽  
Robert Myers ◽  
Richard Steece ◽  
...  

ABSTRACT U.S. gonorrhea rates are rising, and antibiotic-resistant Neisseria gonorrhoeae (AR-Ng) is an urgent public health threat. Since implementation of nucleic acid amplification tests for N. gonorrhoeae identification, the capacity for culturing N. gonorrhoeae in the United States has declined, along with the ability to perform culture-based antimicrobial susceptibility testing (AST). Yet AST is critical for detecting and monitoring AR-Ng. In 2016, the CDC established the Antibiotic Resistance Laboratory Network (AR Lab Network) to shore up the national capacity for detecting several resistance threats including N. gonorrhoeae. AR-Ng testing, a subactivity of the CDC’s AR Lab Network, is performed in a tiered network of approximately 35 local laboratories, four regional laboratories (state public health laboratories in Maryland, Tennessee, Texas, and Washington), and the CDC’s national reference laboratory. Local laboratories receive specimens from approximately 60 clinics associated with the Gonococcal Isolate Surveillance Project (GISP), enhanced GISP (eGISP), and the program Strengthening the U.S. Response to Resistant Gonorrhea (SURRG). They isolate and ship up to 20,000 isolates to regional laboratories for culture-based agar dilution AST with seven antibiotics and for whole-genome sequencing of up to 5,000 isolates. The CDC further examines concerning isolates and monitors genetic AR markers. During 2017 and 2018, the network tested 8,214 and 8,628 N. gonorrhoeae isolates, respectively, and the CDC received 531 and 646 concerning isolates and 605 and 3,159 sequences, respectively. In summary, the AR Lab Network supported the laboratory capacity for N. gonorrhoeae AST and associated genetic marker detection, expanding preexisting notification and analysis systems for resistance detection. Continued, robust AST and genomic capacity can help inform national public health monitoring and intervention.


2015 ◽  
Vol 81 (17) ◽  
pp. 6024-6037 ◽  
Author(s):  
Matthew J. Stasiewicz ◽  
Haley F. Oliver ◽  
Martin Wiedmann ◽  
Henk C. den Bakker

ABSTRACTWhile the food-borne pathogenListeria monocytogenescan persist in food associated environments, there are no whole-genome sequence (WGS) based methods to differentiate persistent from sporadic strains. Whole-genome sequencing of 188 isolates from a longitudinal study ofL. monocytogenesin retail delis was used to (i) apply single-nucleotide polymorphism (SNP)-based phylogenetics for subtyping ofL. monocytogenes, (ii) use SNP counts to differentiate persistent from repeatedly reintroduced strains, and (iii) identify genetic determinants ofL. monocytogenespersistence. WGS analysis revealed three prophage regions that explained differences between three pairs of phylogenetically similar populations with pulsed-field gel electrophoresis types that differed by ≤3 bands. WGS-SNP-based phylogenetics found that putatively persistentL. monocytogenesrepresent SNP patterns (i) unique to a single retail deli, supporting persistence within the deli (11 clades), (ii) unique to a single state, supporting clonal spread within a state (7 clades), or (iii) spanning multiple states (5 clades). Isolates that formed one of 11 deli-specific clades differed by a median of 10 SNPs or fewer. Isolates from 12 putative persistence events had significantly fewer SNPs (median, 2 to 22 SNPs) than between isolates of the same subtype from other delis (median up to 77 SNPs), supporting persistence of the strain. In 13 events, nearly indistinguishable isolates (0 to 1 SNP) were found across multiple delis. No individual genes were enriched among persistent isolates compared to sporadic isolates. Our data show that WGS analysis improves food-borne pathogen subtyping and identification of persistent bacterial pathogens in food associated environments.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Cameron Buckley ◽  
Brian M. Forde ◽  
Ella Trembizki ◽  
Monica M. Lahra ◽  
Scott A. Beatson ◽  
...  

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Silvia Argimón ◽  
Melissa A. L. Masim ◽  
June M. Gayeta ◽  
Marietta L. Lagrada ◽  
Polle K. V. Macaranas ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document