Genomic epidemiology and population structure of Neisseria gonorrhoeae in Norway, 2016–2017

Abstract

This study presents the nationwide epidemiology of Neisseria gonorrhoeae , using whole-genome sequencing of all culture-positive cases, which comprise roughly 40 % of all cases of gonorrhea reported in Norway from 2016 to 2017. Isolates were assigned to sequence types and Bayesian analysis clusters and variation in genes coding for antibiotic resistance was linked to phenotypic resistance data. The study also included isolates taken from the same patients from different anatomical sites at one or more time points. Comparing these isolates allows for observation of patterns of infections, i.e. multiple reinfections of genetically related clones vs. reinfections of genetically distant clones, and quantification of the genomic variation of closely related isolates from samples taken from a patient within the same day. Demographically, the patients in the study could be split into two groups; one group of patients from the capital with a high proportion of men who have sex with men (MSM), and another consisting of young adults with transmission primarily between males and females from outside the capital. Some clusters of N. gonorrhoeae were restricted to one of these two demographic groups. Pairwise comparison of multiple isolates from the same patients revealed that most were reinfected with different clones. Observations of frequent reinfections in patients is a concern and should be taken into account in the development of improved information and treatment guidelines.

Sudden emergence of a Neisseria gonorrhoeae clade with reduced susceptibility to extended-spectrum cephalosporins, Norway

“…Out of 370 PC-7827 isolates, 362 harboured the gyrA S91F mutation, and the vast majority of isolates carried additional gyrA and parC mutations. All but one strain tested were phenotypically resistant to ciprofloxacin (Table S1), which is in line with early observations of ST-7827 [ 32 ]. The mtrR promoter deletion −35A was universally present in the genogroup, except for a cluster where the mutation had reverted and which carried a mosaic mtrD .…”

Antibiotic Treatment Regimes as a Driver of the Global Population Dynamics of a Major Gonorrhea Lineage

“…The first two STs have been described as single-locus variants of ST-1901 ( Yahara et al. 2018 ) and all four STs were found embedded within the ST-1901 genome-based phylogeny in a previous analysis of Norwegian gonococcal genomes ( Alfsnes et al. 2020 ).…”

A community-driven resource for genomic epidemiology and antimicrobial resistance prediction of Neisseria gonorrhoeae at Pathogenwatch

“…Of the studies where these mtr mosaic-carrying genomes were obtained from, only those from the USA and Australia specifically targeted and found this genetic determinant of resistance. The rest did not target this mosaic and some of them found strains with unexplained increased MICs of azithromycin [70,121,129], which could partly be explained by the presence of these mtr mosaics.…”

“…6b). Despite the genomic data contained in Pathogenwatch being biased to the amount of data sequenced and published from each country and year, we can easily infer that this lineage has spread across the world as we detect cases in Australia (n = 293) [118], the USA (n = 195) [18,120,122,123], Norway (n = 19) [121], the UK (n = 11) [69,119] and Ireland (n = 3) [129]. A strong association was found to the country of isolation (Fig.…”