To Örebro University

Background: Since 2009, the European Centre for Disease Prevention and Control (ECDC) has coordinated the European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) to monitor antimicrobial resistance (AMR) in Neisseria gonorrhoeae across the European Union and European Economic Area (EU/EEA). The aims of this study were to report Euro-GASP 2022 data and to compare with the most recently published Euro-GASP data (from 2016 to 2019), to identify changes in AMR and in risk groups for AMR.

Methods: In this observational study, 23 EU/EEA countries submitted AMR data for gonococcal isolates from 2022, linked to patient epidemiological data, to The European Surveillance System (TESSy). Statistical analyses (Z-test) were used to determine the significance of the differences between the epidemiological data and proportion of AMR isolates in 2022 versus 2019 and 2016. The risk factors associated with AMR isolates were assessed using univariate and multivariable logistic regression analyses of odds ratios.

Findings: Ceftriaxone resistance in 2022 (0.03%, 1/3008) remained low (0.06% (2/3239) in 2019), and cefixime resistance (0.3%, 10/3008) had decreased (0.8% (26/3239) in 2019). Azithromycin resistance (24.9%, 749/3008) and ciprofloxacin resistance (65.8%, 1980/3008) had increased (9.0% (284/3159) and 57.4% (1665/2884), respectively, in 2019). A marked increase in the number (575; 502 in 2019) and proportion (19.2%; 15.8% in 2019) of female gonorrhoea cases was also identified in 2022. In the univariate analysis, azithromycin resistance was associated with oropharyngeal (OR 1.67, CI 1.28-2.18; p < 0.0001) and anorectal infections (OR 1.38, CI 1.08-1.76; p = 0.0094), men-who-have-sex-with-men (MSM) (OR 3.88, CI 2.80-5.37; p < 0.0001), and females (1.71, CI 1.21-2.41; p = 0.0022). In the multivariable logistic regression model, only azithromycin resistance and MSM remained associated (OR 2.85, CI 1.33-4.73; p = 0.0040).

Interpretation: While ceftriaxone resistance remains sporadically detected in Euro-GASP, the increase in reports of occasional ceftriaxone resistance in EU/EEA countries and substantial increase in azithromycin resistance underscore the urgent need for enhanced AMR surveillance. The Euro-GASP data is crucial for refining treatment guidelines and mitigating the spread of AMR gonococcal strains. Novel effective antimicrobials for gonorrhoea treatment remain imperative.

OBJECTIVES: Doxycycline post-exposure prophylaxis (doxycycline-PEP) can reduce incident cases of syphilis, chlamydia and possibly gonorrhoea especially among men who have sex with men with recent bacterial sexually transmitted infections (STIs). Owing to potential implementation of doxycycline-PEP internationally, global tetracycline/doxycycline resistance data for contemporary Neisseria gonorrhoeae isolates has become imperative. We report tetracycline resistance data for gonococcal isolates (n = 2993) from eight WHO Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP) countries in three WHO regions in 2021-2024, i.e. to estimate potential impact of doxycycline-PEP on the incident gonorrhoea cases in these WHO EGASP countries.

METHODS: WHO EGASP isolates cultured from men with urethral discharge in Cambodia (n = 482), Indonesia (n = 101), Malawi (n = 121), The Philippines (n = 843), South Africa (n = 597), Thailand (n = 250), Uganda (n = 350) and Vietnam (n = 249) in 2021-2024 were examined. MICs (mg/L) of tetracycline were determined using Etest.

RESULTS: The tetracycline resistance (range) using the current EUCAST (MIC > 0.5 mg/L) and CLSI (MIC > 1 mg/L) clinical resistance breakpoints in the eight WHO EGASP countries was 92.2% (83.5%-99.6%) and 80.6% (66.3%-98.6%), respectively. Using a previous minocycline-PEP resistance breakpoint (MIC > 2 mg/L) and breakpoint for high-level plasmid (tetM)-mediated tetracycline resistance (MIC > 8 mg/L), the tetracycline resistance (range) was 77.3% (47.4%-98.6%) and 74.3% (31.3%-98.6%), respectively.

CONCLUSIONS: The exceedingly high levels of gonococcal tetracycline resistance (independent of resistance breakpoint used) in the eight WHO EGASP countries elucidate that doxycycline-PEP will unlikely significantly reduce the gonorrhoea cases in these countries. Furthermore, doxycycline-PEP might rapidly select for additional gonococcal strains with tetracycline resistance (low- and high-level) and MDR/XDR strains, i.e. because these strains are mostly resistant to tetracycline.

OBJECTIVES: Zoliflodacin, a novel spiropyrimidinetrione, showed non-inferiority compared with recommended ceftriaxone plus azithromycin treatment in a recent global phase III randomized controlled trial for gonorrhea treatment. We evaluated the susceptibility of zoliflodacin among 2993 contemporary gonococcal isolates collected in 2021-2024 in eight World Health Organization (WHO) Enhanced Gonococcal Antimicrobial Surveillance Programme countries in the WHO Southeast Asian Region (Indonesia, Thailand), WHO Western Pacific Region (Cambodia, the Philippines, Viet Nam), and WHO African Region (Malawi, South Africa, Uganda).

METHODS: Minimum inhibitory concentrations (MICs) of zoliflodacin were determined using the agar dilution technique, and the zoliflodacin target gene (gyrB) was examined with Illumina sequencing.

RESULTS: Zoliflodacin exhibited high activity: MICs ranging from 0.001 to 1 mg/l and a modal MIC of 0.032 mg/l. The zoliflodacin MIC distribution showed mostly a wild-type profile; however, two isolates from Cambodia had MICs of 0.5 mg/l and 1 mg/l. These isolates also harbored the GyrB D429N mutation, associated with increased zoliflodacin MICs.

CONCLUSIONS: We show a high susceptibility to zoliflodacin internationally, including against ceftriaxone- and azithromycin-resistant gonococcal strains. Our findings support the continued clinical development of zoliflodacin as a treatment for gonorrhea, although cautious and monitored introduction and continuous international resistance surveillance are imperative.

Gonorrhoea is a prevalent sexually transmitted infection caused by the bacterial pathogen Neisseria gonorrhoeae. N. gonorrhoeae has demonstrated a remarkable capacity to evolve antibiotic resistance, with emerging strains that show resistance to all standard treatment options. The development of new antibiotics for gonorrhoea, especially those with novel targets and no pre-existing resistance, is critical. One such untapped antibacterial target in N. gonorrhoeae is FabI, an enoyl-acyl carrier protein reductase enzyme that is essential for fatty acid biosynthesis in this pathogen. In the current report, structure-based drug design using novel N. gonorrhoeae FabI inhibitor co-crystals guides medicinal chemistry toward increasing potency in the sub-nanomolar range and drives the discovery of Debio 1453. Debio 1453 is optimized for activity against N. gonorrhoeae and is highly active in vitro against diverse N. gonorrhoeae isolates including those resistant to the last remaining treatment options. Additionally, the compound presents a low propensity for selection of mutants with reduced susceptibility. Debio 1453 is efficacious in vivo against N. gonorrhoeae isolates with clinically relevant multi-drug resistance phenotypes in a murine vaginal gonorrhoea infection model underscoring Debio 1453 as a promising candidate for the treatment of gonorrhoea.

Microbiology reference laboratories perform a crucial role within public health systems. This role was especially evident during the COVID-19 pandemic. In this Viewpoint, we emphasise the importance of microbiology reference laboratories and highlight the types of digital data and expertise they provide, which benefit national and international public health. We also highlight the value of surveillance initiatives among collaborative international partners, who work together to share, analyse, and interpret data, and then disseminate their findings in a timely manner. Microbiology reference laboratories have substantial impact at regional, national, and international levels, and sustained support for these laboratories is essential for public health in both pandemic and non-pandemic times.

BACKGROUND: Gonorrhoea and gonococcal antimicrobial resistance (AMR) remain global public health concerns, and enhanced quality-assured global surveillance of gonococcal AMR is imperative to inform management guidelines and public health policies. We aimed to describe the results of surveillance of gonococcal AMR conducted globally by WHO and discuss the actions needed to retain our ability to treat gonorrhoea.

METHODS: In this retrospective observational study, we present gonococcal AMR data reported to WHO by 77 countries between Jan 1, 2019, and Dec 31, 2022. Gonococcal isolates were tested for minimum inhibitory concentrations of one to four key antimicrobials (ceftriaxone, cefixime, azithromycin, and ciprofloxacin) in each country. We used breakpoints for resistance and decreased susceptibility to antimicrobials from the European Committee on Antimicrobial Susceptibility Testing or Clinical Laboratory and Standards Institute.

FINDINGS: 29 (39%) of 75 participating countries reported at least one isolate with resistance or decreased susceptibility to ceftriaxone, 28 (50%) of 56 reported resistance or decreased susceptibility to cefixime, 58 (88%) of 66 reported resistance to azithromycin, and 74 (99%) of 75 reported resistance to ciprofloxacin. Globally, azithromycin resistance is increasing, as is resistance or decreased susceptibility to ceftriaxone and cefixime, especially in the WHO Western Pacific region. Resistance to ciprofloxacin remained very high globally. Since 2017-18, the numbers of reporting countries, examined isolates, and resistant isolates have increased. However, surveillance levels remain inadequate in central America and the Caribbean, eastern Europe, and the WHO African, Eastern Mediterranean, and South-East Asia regions.

INTERPRETATION: Global AMR surveillance conducted by WHO is expanding and, in selected countries, improving through standardisation and quality assurance, as well as implementation of extragenital sampling, test of cure, and whole-genome sequencing. This approach provides evidence-based data for management guidelines and public health policies. Improvements in prevention, early diagnosis, treatment of patients and their contacts, surveillance (of infection rates, AMR, treatment failures, and antimicrobial use), and antimicrobial stewardship are essential. WHO supports this work through several global action plans on AMR, new global gonorrhoea treatment recommendations, surveillance, and research.

INTRODUCTION: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a global public health concern and enhanced global gonococcal AMR surveillance is imperative. As in many African countries, regular, representative and quality-assured gonococcal AMR is lacking in Ethiopia. We describe the AMR in gonococcal isolates from five cities across Ethiopia, 2021-22, and patient epidemiological data.

METHODS: Urethral discharge from males and cervical discharge from females were collected from October 2021 to September 2022. Epidemiological data were collected using a questionnaire. MIC determination (ETEST; eight antimicrobials) was performed on gonococcal isolates and EUCAST breakpoints (v13.1) were used.

RESULTS: From 1142 urogenital swab samples, 299 species-identified gonococcal isolates were identified; 78.3% were from males and 21.7% from females. The median age for males and females was 25 and 23 years, respectively. Most isolates (61.2%) were identified in Addis Ababa, followed by Gondar (11.4%), Adama (10.4%), Bahir Dar (10.0%) and Jimma (7.0%). The resistance level to ciprofloxacin, tetracycline and benzylpenicillin was 97.0%, 97.0% and 87.6%, respectively, and 87.6% of isolates were producing β-lactamase. All isolates were susceptible to ceftriaxone, cefixime, azithromycin and spectinomycin. Recommended therapy [ceftriaxone (250 mg) plus azithromycin (1 g)] was used for 84.2% of patients.

CONCLUSIONS: We present the first national quality-assured gonococcal AMR data from Ethiopia. Resistance levels to ciprofloxacin, tetracycline and benzylpenicillin were exceedingly high. However, all isolates were susceptible to ceftriaxone, cefixime, azithromycin and spectinomycin. In Ethiopia, it is essential to strengthen the gonococcal AMR surveillance by including further epidemiological data, more isolates from different cities, and WGS.

BACKGROUND: Regular quality-assured whole-genome sequencing linked to antimicrobial resistance (AMR) and patient metadata is imperative to elucidate the shifting gonorrhoea epidemiology, both nationally and internationally. We aimed to examine the gonococcal population in the European Economic Area (EEA) in 2020, elucidate emerging and disappearing gonococcal lineages associated with AMR and patient metadata, compare with 2013 and 2018 whole-genome sequencing data, and explain changes in gonococcal AMR and gonorrhoea epidemiology.

METHODS: In this retrospective genomic surveillance study, we analysed consecutive gonococcal isolates that were collected in EEA countries through the European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) in 2020, and made comparisons with Euro-GASP data from 2013 and 2018. All isolates had linked AMR data (based on minimum inhibitory concentration determination) and patient metadata. We performed whole-genome sequencing and molecular typing and AMR determinants were derived from quality-checked whole-genome sequencing data. Links between genomic lineages, AMR, and patient metadata were examined.

FINDINGS: 1932 gonococcal isolates collected in 2020 in 21 EEA countries were included. The majority (81·2%, 147 of 181 isolates) of azithromycin resistance (present in 9·4%, 181 of 1932) was explained by the continued expansion of the Neisseria gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) clonal complexes (CCs) 63, 168, and 213 (with mtrD/mtrR promoter mosaic 2) and the novel NG-STAR CC1031 (semi-mosaic mtrD variant 13), associated with men who have sex with men and anorectal or oropharyngeal infections. The declining cefixime resistance (0·5%, nine of 1932) and negligible ceftriaxone resistance (0·1%, one of 1932) was largely because of the progressive disappearance of NG-STAR CC90 (with mosaic penA allele), which was predominant in 2013. No known resistance determinants for novel antimicrobials (zoliflodacin, gepotidacin, and lefamulin) were found.

INTERPRETATION: Azithromycin-resistant clones, mainly with mtrD mosaic or semi-mosaic variants, appear to be stabilising at a relatively high level in the EEA. This mostly low-level azithromycin resistance might threaten the recommended ceftriaxone-azithromycin therapy, but the negligible ceftriaxone resistance is encouraging. The decreased genomic population diversity and increased clonality could be explained in part by the COVID-19 pandemic resulting in lower importation of novel strains into Europe.

BACKGROUND: Invasive meningococcal disease (IMD), including sepsis and meningitis, can develop when Neisseria meningitidis bacteria breach the barrier and gain access to the circulation. While IMD is a rare outcome of bacterial exposure, colonization of the oropharynx is present in approximately 10% of the human population. This asymptomatic carriage can be long or short term, and it is unknown which determining factors regulate bacterial colonization. Despite descriptions of many bacterial virulence factors and recent advances in detailed genetic identification and characterization of bacteria, the factors mediating invasion and disease vs. asymptomatic carriage following bacterial colonization remain unknown. The pharyngeal epithelia play a role in the innate immune defense against pathogens, and the aim of this study was to investigate the proinflammatory response of pharyngeal epithelial cells following meningococcal exposure to describe the potential inflammatory mediation performed during the initial host‒pathogen interaction. Clinically relevant isolates of serogroups B, C, W and Y, derived from patients with meningococcal disease as well as asymptomatic carriers, were included in the study.

RESULTS: The most potent cellular response with proinflammatory secretion of TNF, IL-6, CXCL8, CCL2, IL-1β and IL-18 was found in response to invasive serogroup B isolates. This potent response pattern was also mirrored by increased bacterial adhesion to cells as well as induced cell death. It was, however, only with serogroup B isolates where the most potent cellular response was toward the IMD isolates. In contrast, the most potent cellular response using serogroup Y isolates was directed toward the carriage isolates rather than the IMD isolates. In addition, by comparing isolates from outbreaks in Sweden (epidemiologically linked and highly genetically similar), we found the most potent proinflammatory response in cells exposed to carriage isolates rather than the IMD isolates.

CONCLUSION: Although certain expected correlations between host‒pathogen interactions and cellular proinflammatory responses were found using IMD serogroup B isolates, our data indicate that carriage isolates invoke stronger proinflammatory activation of the epithelial lining than IMD isolates.

Objectives: The novel dual-target triazaacenaphthylene, gepotidacin, recently showed promising results in its Phase III randomized controlled trial for the treatment of gonorrhoea. We investigated alterations in the gepotidacin GyrA and ParC targets in gonococci by in silico mining of publicly available global genomes (n = 33 213) and determined gepotidacin MICs in isolates with GyrA A92 alterations combined with other GyrA and/or ParC alterations.

Methods: We examined gonococcal gyrA and parC alleles available at the European Nucleotide Archive. MICs were determined using the agar dilution method (gepotidacin) or Etest (four antimicrobials). Models of DNA gyrase and topoisomerase IV were obtained from AlphaFold and used to model gepotidacin in the binding site.

Results: GyrA A92 alterations were identified in 0.24% of genomes: GyrA A92P/S/V + S91F + D95Y/A/N (0.208%), A92P + S91F (0.024%) and A92P (0.003%), but no A92T (previously associated with gepotidacin resistance) was found. ParC D86 alterations were found in 10.6% of genomes: ParC D86N/G (10.5%), D86N + S87I (0.051%), D86N + S88P (0.012%) and D86G + E91G (0.003%). One isolate had GyrA A92P + ParC D86N alterations, but remained susceptible to gepotidacin (MIC = 0.125 mg/L). No GyrA plus ParC alterations resulted in a gepotidacin MIC > 4 mg/L. Modelling of gepotidacin binding to GyrA A92/A92T/A92P suggested that gepotidacin resistance due to GyrA A92T might be linked to the formation of a new polar contact with DNA.

Conclusions: In silico mining of 33 213 global gonococcal genomes (isolates from 1928 to 2023) showed that A92 is highly conserved in GyrA, while alterations in D86 of ParC are common. No GyrA plus ParC alterations caused gepotidacin resistance. MIC determination and genomic surveillance of potential antimicrobial resistance determinants are imperative.