Australian Gonococcal Surveillance Programme Annual Report, 2018

The changing epidemiology of Neisseria gonorrhoeae genogroups and antimicrobial resistance in Queensland, Australia, 2010-15: a case series analysis of unique Neisseria gonorrhoeae isolates

BACKGROUND

Neisseria gonorrhoeae (NG) can lead to serious reproductive and sexual health outcomes, and the annual number of NG notifications in Australia increased steadily from 10329 in 2010 to 29549 by 2020. Australian populations most affected are urban men who have sex with men and First Nations peoples living in remote areas, and a resurgence in urban heterosexuals has been observed since 2012.

METHODS

A case series analysis of Queensland NG isolates (2010-15) exploring temporal trends and antimicrobial resistance by demographic and geographic distribution and genotype was performed. Proportions describe age, sex, strain, genogroup (NG multi-antigen sequence typing), region, swab site, antimicrobial sensitivity and isolate rates per 100000 population. Dominant genogroups were identified.

RESULTS

Among 3953 isolates, the median age was 25years (IQR 20-34years) and most (n =2871/3915, 73%) were men. Brisbane city (68.8) and Far North Queensland (54.1) excluding Cairns showed the highest rates. Forty-six genogroups were documented, seven (G2992, G6876, G1415, G4186, G5, G1407 and G6937) comprised half of all isolates. The predominant male genogroup was G2992 (16%), and G6876 (20%) for females; G5 was predominantly male from 2010 to 2011, but equal in both sexes from 2012 to 2015.

CONCLUSION

Considerable temporal, geographical and demographical diversity was observed in Queensland NG isolates, which has public health implications. Certain genogroups are more transient than others, and evidence suggests bridging from male-dominant networks to heterosexual networks. Molecular surveillance can enhance tracking the epidemiology and movement of NG in Australia, highlighting the necessity of genotyping to expose potentially prevalent strains circulating in undetected or underrepresented networks by current screening methods.

An Observational Study to Assess the Effectiveness of 4CMenB against Meningococcal Disease and Carriage and Gonorrhea in Adolescents in the Northern Territory, Australia—Study Protocol

Invasive meningococcal disease (IMD) causes significant morbidity and mortality worldwide with serogroup B being the predominant serogroup in Australia and other countries for the past few decades. The licensed 4CMenB vaccine is effective in preventing meningococcal B disease. Emerging evidence suggests that although 4CMenB impact on carriage is limited, it may be effective against gonorrhoea due to genetic similarities between Neisseria meningitidis and Neisseria gonorrhoeae. This study protocol describes an observational study that will assess the effect of the 4CMenB vaccine against meningococcal carriage, IMD and gonorrhoea among adolescents in the Northern Territory (NT). All 14–19-year-olds residing in the NT with no contraindication for 4CMenB vaccine will be eligible to participate in this cohort study. Following consent, two doses of 4CMenB vaccine will be administered two months apart. An oropharyngeal swab will be collected at baseline and 12 months to detect pharyngeal carriage of Neisseria meningitidis by PCR. The main methodological approaches to assess the effect of 4CMenB involve a nested case control analysis and screening method to assess vaccine effectiveness and an Interrupted Time Series regression analysis to assess vaccine impact. Research ethics approvals have been obtained from Menzies and Central Australian Human Research Ethics Committees and the Western Australian Aboriginal Health Ethics Committee. Results will be provided in culturally appropriate formats for NT remote and regional communities and published in international peer reviewed journals. ClinicalTrials.gov Identifier: NCT04398849

Australian Gonococcal Surveillance Programme Annual Report, 2020

Abstract

The Australian Gonococcal Surveillance Programme (AGSP), established in 1981, has continuously monitored antimicrobial resistance in clinical isolates of Neisseria gonorrhoeae for more than 40 years. In 2020, a total of 7,222 clinical isolates of gonococci from patients in the public and private sectors, in all jurisdictions, were tested for in vitro antimicrobial susceptibility by standardised methods. Current treatment recommendations for gonorrhoea, for the majority of Australia, continues to be dual therapy with ceftriaxone and azithromycin. In 2020, decreased susceptibility (DS) to ceftriaxone (minimum inhibitory concentration [MIC] value ≥ 0.06 mg/L) was found nationally in 0.9% of isolates. There was one isolate, reported from Victoria in 2020, that was resistant to ceftriaxone (MIC value ≥ 0.25 mg/L). Resistance to azithromycin (MIC value ≥ 1.0 mg/L) was found nationally in 3.9% of N. gonorrhoeae isolates, continuing a downward trend observed and reported since 2017. Isolates with high-level resistance to azithromycin (MIC value ≥ 256 mg/L) are identified sporadically in Australia; in 2020, there was one such isolate reported in Queensland. In 2020, penicillin resistance was found in 27% of gonococcal isolates nationally, and ciprofloxacin resistance in 36%; however, there is considerable variation by jurisdiction. In some remote settings, penicillin resistance remains low, and this drug continues to be recommended as part of an empiric therapy strategy. In 2020, in remote Northern Territory, no penicillin resistance was reported, and in remote Western Australia 5/116 of gonococcal isolates (4.3%) were penicillin resistant. There was one ciprofloxacin-resistant isolate reported from remote Northern Territory, and ciprofloxacin resistance rates remain comparatively low in remote Western Australia (4/116; 3.4%).

Australian Gonococcal Surveillance Programme Annual Report, 2020

Abstract

The Australian Gonococcal Surveillance Programme (AGSP), established in 1981, has continuously monitored antimicrobial resistance in clinical isolates of Neisseria gonorrhoeae for more than 40 years. In 2020, a total of 7,219 clinical isolates of gonococci from patients in the public and private sectors, in all jurisdictions, were tested for in vitro antimicrobial susceptibility by standardised methods. Current treatment recommendations for gonorrhoea, for the majority of Australia, continues to be dual therapy with ceftriaxone and azithromycin. In 2020, decreased susceptibility (DS) to ceftriaxone (minimum inhibitory concentration [MIC] value ≥ 0.06 mg/L) was found nationally in 0.9% of isolates. There was one isolate, reported from Victoria in 2020, that was resistant to ceftriaxone (MIC value ≥ 0.25 mg/L). Resistance to azithromycin (MIC value ≥ 1.0 mg/L) was found nationally in 3.9% of N. gonorrhoeae isolates, continuing a downward trend observed and reported since 2017. Isolates with high-level resistance to azithromycin (MIC value ≥ 256 mg/L) are identified sporadically in Australia; in 2020, there was one such isolate reported in Queensland. In 2020, penicillin resistance was found in 27% of gonococcal isolates nationally, and ciprofloxacin resistance in 36%; however, there is considerable variation by jurisdiction. In some remote settings, penicillin resistance remains low, and this drug continues to be recommended as part of an empiric therapy strategy. In 2020, in remote Northern Territory, no penicillin resistance was reported, and in remote Western Australia 5/116 of gonococcal isolates (4.3%) were penicillin resistant. There was one ciprofloxacin-resistant isolate reported from remote Northern Territory, and ciprofloxacin resistance rates remain comparatively low in remote Western Australia (4/116; 3.4%).

Susceptibility Trends of Zoliflodacin against Multidrug-Resistant Neisseria gonorrhoeae Clinical Isolates in Nanjing, China, 2014 to 2018

Previously, we reported the potent activity of a novel spiropyrimidinetrione, zoliflodacin, against Neisseria gonorrhoeae isolates collected in 2013 from symptomatic men in Nanjing, China. Here, we investigated trends of susceptibilities to zoliflodacin in 986 isolates collected from men between 2014 and 2018. N. gonorrhoeae isolates were tested for susceptibility to zoliflodacin and seven other antibiotics. Mutations in the gyrA, gyrB, parC, parE, and mtrR genes were determined by PCR and sequencing. The MICs of zoliflodacin ranged from ≤0.002 to 0.25 mg/liter; the overall MIC50 and MIC90 were 0.06 mg/liter and 0.125 mg/liter, respectively, in 2018, increasing 2-fold from 2014. However, the percentage of isolates with lower zoliflodacin MICs declined in each year sequentially, while the percentage with higher MICs increased yearly (P ≤ 0.00001). All isolates were susceptible to spectinomycin but resistant to ciprofloxacin (MIC ≥ 1 mg/liter); 21.2% (209/986) were resistant to azithromycin (≥1 mg/liter), 43.4% (428/986) were penicillinase-producing N. gonorrhoeae (PPNG), 26.9% (265/986) were tetracycline-resistant N. gonorrhoeae (TRNG), and 19.4% (191/986) were multidrug-resistant (MDR) isolates. 202 isolates with the lowest (≤0.002 to 0.015 mg/liter) and highest (0.125 to 0.25 mg/liter) zoliflodacin MICs were quinolone resistant with double or triple mutations in gyrA; 193/202 (95.5%) also had mutations in parC There were no D429N/A and/or K450T mutations in GyrB identified in the 143 isolates with higher zoliflodacin MICs; an S467N mutation in GyrB was identified in one isolate. We report that zoliflodacin continues to have excellent in vitro activity against clinical gonococcal isolates, including those with high-level resistance to ciprofloxacin, azithromycin, and extended-spectrum cephalosporins.

Australian Gonococcal Surveillance Programme: 1 July to 30 September 2019

The National Neisseria Network (NNN), Australia, comprises reference laboratories in each state and territory that report data on susceptibility profiles for clinical Neisseria gonorrhoeae isolates from each jurisdiction for an agreed group of antimicrobial agents, for the Australian Gonococcal Surveillance Programme (AGSP). The antibiotics are ceftriaxone, azithromycin, ciprofloxacin and penicillin; they represent current or potential agents used for the treatment of gonorrhoea. Ceftriaxone combined with azithromycin is the recommended treatment regimen for gonorrhoea in the majority of Australia. However, there are substantial geographic differences in susceptibility patterns in Australia, with certain remote regions of the Northern Territory and Western Australia having low gonococcal antimicrobial resistance rates. In these regions, an oral treatment regimen comprising amoxycillin, probenecid and azithromycin is recommended for the treatment of gonorrhoea. Additional data on other antibiotics are reported in the AGSP Annual Report. The AGSP has a programme-specific quality assurance process.

Australian Gonococcal Surveillance Programme, 1 January to 31 March 2020

The National Neisseria Network (NNN), Australia, comprises reference laboratories in each state and territory that report data on susceptibility profiles for clinical Neisseria gonorrhoeae isolates from each jurisdiction for an agreed group of antimicrobial agents for the Australian Gonococcal Surveillance Programme (AGSP). The antibiotics (ceftriaxone, azithromycin, ciprofloxacin, and penicillin) represent current or potential agents used for the treatment of gonorrhoea. Ceftriaxone, combined with azithromycin, is the recommended treatment regimen for gonorrhoea in the majority of Australia. However, there are substantial geographic differences in susceptibility patterns in Australia, with certain remote regions of the Northern Territory and Western Australia having low gonococcal antimicrobial resistance rates. In these regions, an oral treatment regimen comprising amoxycillin, probenecid, and azithromycin is recommended for the treatment of gonorrhoea. Additional data on other antibiotics are reported in the AGSP Annual Report. The AGSP has a programme-specific quality assurance process.

Australian Gonococcal Surveillance Programme Annual Report, 2019

The Australian Gonococcal Surveillance Programme (AGSP) has continuously monitored antimicrobial resistance in clinical isolates of Neisseria gonorrhoeae since 1981. In 2019, a total of 9,668 clinical isolates of gonococci from the public and private sector in all jurisdictions were tested for in vitro antimicrobial susceptibility by standardised methods. The current treatment recommendation for gonorrhoea, for the majority of Australia, continues to be dual therapy with ceftriaxone and azithromycin. Decreased susceptibility (DS) to ceftriaxone (minimum inhibitory concentration [MIC] value ≥ 0.06 mg/L) was found nationally in 1.3% of isolates. Five N. gonorrhoeae clinical isolates were ceftriaxone-resistant (MIC value ≥ 0.25 mg/L), and therefore also resistant to penicillin; all were resistant to ciprofloxacin but susceptible to azithromycin. These isolates were reported from Victoria (3), non-remote Western Australia (1) and New South Wales (1). Resistance to azithromycin (MIC value ≥ 1.0 mg/L) was found nationally in 4.6% of N. gonorrhoeae isolates, continuing a downward trend observed and reported since 2017. Isolates with high-level resistance to azithromycin (MIC value ≥ 256 mg/L) continue to be reported sporadically in Australia, with eight detected in 2019: two each from New South Wales, Queensland, and Victoria, and one each from Tasmania and non-remote Western Australia. In 2019, in Australia, 2,136 gonococcal isolates (22.1%) were penicillin resistant; however, there remains considerable variation by jurisdiction, and in some remote settings there is little resistance and this drug is recommended empiric therapy. In 2019, in the remote Northern Territory, no penicillin resistance was reported, however in remote Western Australia six out of 85 isolates (7.1%) were penicillin resistant. There was no ciprofloxacin resistance reported from isolates tested from remote regions of the Northern Territory, and ciprofloxacin resistance rates remain comparatively low (7/85; 8.2%) in remote Western Australia.