Emerging cephalosporin and multidrug-resistant gonorrhoea in Europe.

Neisseria gonorrhoeae has consistently developed resistance to antimicrobials used therapeutically for gonorrhoea and few antimicrobials remain for effective empiric first-line therapy. Since 2009 the European gonococcal antimicrobial surveillance programme (Euro-GASP) has been running as a sentinel surveillance system across Member States of the European Union (EU) and European Economic Area (EEA) to monitor antimicrobial susceptibility in N. gonorrhoeae. During 2011, N. gonorrhoeae isolates were collected from 21 participating countries, and 7.6% and 0.5% of the examined gonococcal isolates had in vitro resistance to cefixime and ceftriaxone, respectively. The rate of ciprofloxacin and azithromycin resistance was 48.7% and 5.3%, respectively. Two (0.1%) isolates displayed high-level resistance to azithromycin, i.e. a minimum inhibitory concentration (MIC) ≥256 mg/L. The current report further highlights the public health need to implement the European response plan, including further strengthening of Euro-GASP, to control and manage the threat of multidrug resistant N. gonorrhoeae.

Molecular epidemiological typing within the European Gonococcal Antimicrobial Resistance Surveillance Programme reveals predominance of a multidrug-resistant clone.

Treatment of gonorrhoea is threatened by antimicrobial resistance, and decreased susceptibility and resistance to recommended therapies is emerging in Europe. Current associations between resistance and molecular type remain poorly understood. Gonococcal isolates (n=1,066) collected for the 2009 and 2010 European Gonococcal Antimicrobial Surveillance Programme were typed by Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST). A total of 406 sequence types (STs) were identified, 125 of which occurred in ≥two isolates. Seven major genogroups of closely related STs (varying by ≤1% at just one of the two target loci) were defined. Genogroup 1407 (G1407), observed in 20/21 countries and predominant in 13/21 countries, accounted for 23% of all isolates and was associated with decreased susceptibility to cefixime and resistance to ciprofloxacin and raised minimum inhibitory concentrations for ceftriaxone and azithromycin. Genogroup 225 (G225), associated with ciprofloxacin resistance, was observed in 10% of isolates from 19/21 countries. None of the other genogroups were associated with antimicrobial resistance. The predominance of a multidrug-resistant clone (G1407) in Europe is worrying given the recent reports of recommended third generation cephalosporins failing to treat infections with this clone. Identifying associations between ST and antimicrobial resistance aids the understanding of the dissemination of resistant clones within a population and could facilitate development of targeted intervention strategies.

Rapid increase in gonorrhoea and syphilis diagnoses in England in 2011.

There has been a rapid rise in the number of gonorrhoea and syphilis diagnoses in England during 2011, an increase of 25% and 10% respectively. Large increases of both gonorrhoea (61%) and syphilis (28%) were observed among men who have sex with men. Although these rises can partly be attributed to increased testing, ongoing high-levels of unsafe sexual behaviour probably contributed to the rise. The rise in gonorrhoea rates is worrying in an era of decreased susceptibility to treatments.

Gonorrhoea treatment failures to cefixime and azithromycin in England, 2010.

Successful treatment of gonorrhoea is the mainstay of public health control. Cefixime and ceftriaxone, highly active third generation cephalosporins, are today the recommended first-line agents in most countries and azithromycin is a second-line agent. However, there is increasing evidence of decreasing susceptibility and emergence of therapeutic failures. In this report two cases of clinical failure to cefixime are described, one of which additionally shows failure to azithromycin and selection of a less susceptible strain during treatment.

The European gonococcal antimicrobial surveillance programme, 2009.

Neisseria gonorrhoeae antimicrobial susceptibility is monitored in the European Union (EU) and the European Economic Area (EEA) by the European gonococcal antimicrobial surveillance programme (Euro-GASP). Results from 17 EU/EEA Member States in 2009 showed that 5% of isolates had decreased susceptibility to cefixime, an upward trend in the minimum inhibitory concentrations of ceftriaxone and a high prevalence of resistance to ciprofloxacin (63%)and azithromycin (13%). These results are of public health value and highlight the need for healthcare professionals to be aware of possible cefixime treatment failures. Euro-GASP is being implemented in additional EU/EEA Member States to achieve greater representativeness. In addition, Euro-GASP aims to set up a system which will allow biannual reporting of antimicrobial resistance in the EU/EEA, with a transition from centralised towards decentralised testing,and will link epidemiological data to laboratory data to enhance surveillance. The benefits of this approach include more timely detection of emerging trends in gonococcal resistance across the EU/EEA and the provision of a robust evidence base for informing national and European guidelines for therapy.

Emergence of high-level azithromycin resistance in Neisseria gonorrhoeae in England and Wales.

OBJECTIVES: This study aimed to investigate the origin of high-level azithromycin resistance that emerged in isolates of Neisseria gonorrhoeae in England and Wales in 2007, and to establish methods for identifying high-level azithromycin resistance. METHODS: The Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) data from 2001-07 were examined for emerging trends in azithromycin susceptibility. Further to the identification of six high-level azithromycin-resistant isolates in GRASP 2007, an additional 102 isolates were selected on the basis of azithromycin susceptibility and geographic origin from the GRASP 2006 and 2007 collections. Susceptibility testing by Etest and disc diffusion was performed on all 108 isolates and 75 of these were typed by N. gonorrhoeae multiantigen sequence typing. RESULTS: A slight drift towards higher MICs of azithromycin was observed in the gonococcal population since 2001. Of greater concern was the first example of a shift to high-level resistance observed in six isolates in 2007. All six isolates were sequence type 649, which was not observed in any of the lower-level azithromycin-resistant isolates from 2007 or in any isolates tested from the same geographical locations. Contact tracing data for one patient suggested a link with Scotland. Disc diffusion testing of all 108 isolates showed that azithromycin, but not erythromycin, discs can differentiate between low-level and high-level resistance. CONCLUSIONS: High-level azithromycin resistance has emerged in England and Wales. Contact tracing and typing data suggest this may have originated from Scotland. Surveillance of azithromycin resistance will be key in controlling its further dissemination.

Epidemiology and clinical presentation of gonorrhoea in England and Wales: findings from the Gonococcal Resistance to Antimicrobials Surveillance Programme 2001-2006.

OBJECTIVE: To analyse the enhanced data for gonorrhoea cases in England and Wales collected by the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) to better inform health policy and targeted interventions. METHODS: GRASP data obtained annually from sentinel genitourinary medicine (GUM) clinics between June to August during 2001-6 were analysed. RESULTS: A total of 12 282 cases of gonorrhoea were reported during the study period, with a decline over time primarily in heterosexual patients of black ethnicity. 73% of women, 47% of heterosexual men and 22% of men who have sex with men (MSM) were aged under 25. Most infected women reported a single sexual partner in the previous 3 months, whereas most heterosexual men and MSM reported two or more partners. A history of gonorrhoea was reported by 42% of MSM, 30% of heterosexual men and 20% of women. Excluding HIV, women were more likely than men to have a concurrent STI at diagnosis, most commonly chlamydia (50% vs 27% p<0.0005). Rectal gonococcal infections were reported in 35% and HIV co-infection in 31% of MSM. Compared to HIV negative MSM, those co-infected with HIV were older (median 35 years vs 28 years) and were more likely to attend a London site (70% vs 52%, p<0.0005); have a concurrent sexually transmitted infection (STI) (28% vs 20%, p = 0.002); have a history of gonorrhoea (66% vs 36%, p<0.0005) and have more sexual partners (average 6.8 vs 4.3). CONCLUSION: Gonorrhoea is concentrated within specific groups who are at high risk of repeat infections and concurrent STIs including HIV. Targeted interventions of proved effectiveness are urgently required.

Molecular epidemiology of syphilis in Scotland.

OBJECTIVE: To examine the molecular epidemiology of syphilis in Scotland. METHODS: Ulcer specimens were collected from 85 patients with infectious syphilis. Typing of Treponema pallidum was performed using a method that examines variation in two loci; the number of 60-basepair repeats within the arp gene and sequence variation in the tpr genes. RESULTS: Patients were predominately white men who have sex with men (MSM). Treponemal DNA was detected in 75 specimens and a total of six subtypes were identified from 58 typeable specimens (77%). The most common subtypes were 14d (44/58, 76%), followed by 14e (7/58, 12%), 14j (3/58, 5%), 14b (2/58, 3%), 14p and 14k (1/58, 2%). CONCLUSIONS: This study shows that subtype 14d is the predominant subtype circulating in Scotland and there is a surprising level of genetic diversity within the Scottish MSM community.

Audit of laboratory diagnostic methods for syphilis in England and Wales.

OBJECTIVES: The number of cases of infectious syphilis is increasing rapidly across England and Wales. Concern has been expressed about diagnostic delay and its potential impact on patient care. A standard operating procedure for the serological diagnosis of syphilis has recently been developed by the Health Protection Agency. This study aimed to audit clinical and laboratory practice in England and Wales against this standard. METHODS: All microbiology departments, genitourinary medicine (GUM) clinics and antenatal clinics in England and Wales were invited to complete a web-based questionnaire. RESULTS: The overall response rate was 76%. Practices varied between laboratories. The proportion of microbiology departments performing enzyme immunoassay (EIA), Treponema pallidum particle agglutination assay/T pallidum haemagglutination assay, rapid plasma reagin/Venereal Disease Reference Laboratory and EIA IgM were 94%, 34%, 41% and 10%, respectively. Of these, 57% only perform a single screening assay. The turnaround time for negative results was less than 1 week for 84% of microbiology departments. For positive samples, turnaround times varied from less than 1 week to 6-8 weeks, with 19% of GUM clinics reporting turnaround times of over 3 weeks. Notably, 26% of GUM clinics and 6% of antenatal clinics reported that delays in turnaround time had adversely affected patient management in the past year. CONCLUSION: This study suggests that there is significant room to improve laboratory turnaround times for the diagnosis of syphilis in England and Wales, and such improvements would be a positive step in limiting the spread of infection and of congenital syphilis.

The prevalence of lymphogranuloma venereum infection in men who have sex with men: results of a multicentre case finding study.

OBJECTIVE: To determine the prevalence of lymphogranuloma venereum (LGV) and non-LGV associated serovars of urethral and rectal Chlamydia trachomatis (CT) infection in men who have sex with men (MSM). DESIGN: Multicentre cross-sectional survey. SETTING: Four genitourinary medicine clinics in the United Kingdom from 2006-7. SUBJECTS: 4825 urethral and 6778 rectal samples from consecutive MSM attending for sexual health screening. METHODS: Urethral swabs or urine and rectal swabs were tested for CT using standard nucleic acid amplification tests. Chlamydia-positive specimens were sent to the reference laboratory for serovar determination. MAIN OUTCOME: Positivity for both LGV and non-LGV associated CT serovars; proportion of cases that were symptomatic. RESULTS: The positivity (with 95% confidence intervals) in rectal samples was 6.06% (5.51% to 6.66%) for non-LGV CT and 0.90% (0.69% to 1.16%) for LGV; for urethral samples 3.21% (2.74% to 3.76%) for non-LGV CT and 0.04% (0.01% to 0.16%) for LGV. The majority of LGV was symptomatic (95% of rectal, one of two urethral cases); non-LGV chlamydia was mostly symptomatic in the urethra (68%) but not in the rectum (16%). CONCLUSIONS: Chlamydial infections are common in MSM attending for sexual health screening, and the majority are non-LGV associated serovars. We did not identify a large reservoir of asymptomatic LGV in the rectum or urethra. Testing for chlamydia from the rectum and urethra should be included for MSM requesting a sexual health screen, but serovar-typing is not indicated in the absence of symptoms. We have yet to identify the source of most cases of LGV in the UK.

Association of Mycoplasma genitalium with acute non-gonococcal urethritis in Russian men: a comparison with gonococcal and chlamydial urethritis.

Urethral specimens from 172 men who attended sexually transmitted disease clinics in the Moscow Oblast were examined for Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium by nucleic acid amplification tests. N. gonorrhoeae was detected in the urethra of 41 (24%) of the 172 men and C. trachomatis in 57 (33%). The latter occurred in 15 (36%) of the 41 men who were infected by N. gonorrhoeae and in 42 (32%) of 131 uninfected by gonococci. Of the 42 men uninfected by gonococci but chlamydia infected, 39 (93%) had symptoms and/or signs of urethritis. M. genitalium was detected in 45 (26%) of the 172 men, in nine (22%) of the 41 men infected with N. gonorrhoeae and in 12 (21%) infected with C. trachomatis. M. genitalium was detected alone in 25 (28%) of the 89 men uninfected by either gonococci or C. trachomatis. Of these 25 men, 24 (96%) had urethral symptoms and signs of inflammation, a proportion significantly more than experienced by the 64 men uninfected by any of the microorganisms. Of the 31 men who apparently had no symptoms or signs of urethritis, only three (10%) were infected by M. genitalium. The data provide evidence for the pathogenicity and frequent occurrence of M. genitalium in men in Moscow and presumably elsewhere in Russia.

A real-time quadriplex PCR assay for the diagnosis of rectal lymphogranuloma venereum and non-lymphogranuloma venereum Chlamydia trachomatis infections.

OBJECTIVES: To develop and evaluate a real-time quadriplex PCR for the diagnosis of lymphogranuloma venereum (LGV) and non-LGV chlamydial infections using rectal swab specimens. METHODS: The design of the real-time quadriplex PCR assay incorporates an LGV-specific, a non-LGV-specific target sequence, a Chlamydia trachomatis plasmid target, and the human RNase P gene as an internal control. The performance of the quadriplex PCR was compared with a previously reported real-time duplex PCR assay on which LGV diagnosis was based on exclusion. RESULTS: Very good agreement (85 of 89 specimens, 95.5%) was found between the two multiplex PCR assays for the detection of C trachomatis DNA (kappa value 0.93, 95% CI 0.86 to 0.99). Both assays identified 34 LGV, 35 non-LGV C trachomatis and 16 negative specimens. Of two specimens that tested positive for non-LGV by the duplex PCR, one was found to be a mixed infection and the other was positive only for plasmid and RNase P targets by the quadriplex PCR. Two additional specimens that had equivocal results for non-LGV by the duplex PCR also tested positive only for plasmid target and human DNA by the quadriplex PCR. In addition, six specimens that tested negative by the duplex PCR assay were found to be invalid when using the quadriplex PCR. CONCLUSIONS: A real-time quadriplex PCR assay has been developed that is capable of detecting LGV, non-LGV, or mixed infections simultaneously in rectal specimens. The assay also contains a supplemental amplification target for the confirmation of C trachomatis infection as well as a human DNA control for monitoring sample adequacy and PCR inhibition.

Results of a Europe-wide investigation to assess the presence of a new variant of Chlamydia trachomatis.

In 2006, a new variant of Chlamydia trachomatis was reported in Sweden. Three countries - Ireland, Norway, and Denmark - have detected the variant to date, but very few cases in total have occurred. The European network for STI surveillance (ESSTI) and the European Centre for Disease Prevention and Control (ECDC) assessed the potential spread of the variant in other European countries, and concluded that there is currently no evidence that the variant has spread widely across Europe. However, the variant strain has been reported in between 10% and 65% of infected patients in Sweden. It is too early to tell whether the variant will remain confined to Sweden or whether the number of cases will significantly increase. Enhanced surveillance will need to be continued to address these concerns.

Immunogenicity of a serogroup B meningococcal vaccine against multiple Neisseria meningitidis strains in infants.

BACKGROUND: The serogroup B meningococcus is responsible for the majority of cases of meningococcal disease in temperate countries. Infants and young children <2 years of age are at greatest risk of disease. This study assessed the immunogenicity in infants of a serogroup B meningococcal outer membrane protein vaccine that has been used extensively in disease outbreaks in Cuba and several Latin American countries and shown to be efficacious in teenagers. METHOD: One hundred five healthy infants entering the routine vaccination schedule in Havana, Cuba, were given either 2 or 3 doses of the serogroup B meningococcal vaccine VA-MENGOC-BC at 3.5, 5.5 and 7.5 months of age. Immune response pre- and postvaccination was determined by the conventional serum bactericidal assay (SBA), a more sensitive novel whole blood bactericidal assay (WBA) and immunoglobulin ELISA. RESULTS: In 52 and 46% of infants >50% killing of the vaccine serogroup B strain (B:4:P1.19,15) and serogroup C strain, respectively, was demonstrated by the WBA after 2 doses of the vaccine. Serum bactericidal activity (4-fold increase in titer) was induced in only 27% against the vaccine serogroup B strain and in 14% against the serogroup C strain. The changes in WBA and SBA were mirrored by the serogroup B and C immunoglobulin ELISA. Cross-reactive immunogenicity against other (heterologous) serogroup B strains was demonstrated for one of the four further strains assessed by WBA. By age 16 to 18 months SBA, WBA and ELISA responses had declined considerably. The addition of a third dose of vaccine did not appear to significantly influence immunogenicity at 17 months of age. CONCLUSION: The serogroup B outer membrane protein vaccine VA-MENGOC-BC induces a demonstrable immune response in infants against both the serogroup B vaccine strain and against a serogroup C strain. Cross-reactive immunogenicity against other (heterologous) serogroup B strains is limited in this age group.

Susceptibility testing of Neisseria gonorrhoeae to penicillin and spectinomycin in a diagnostic laboratory.

Agar dilution breakpoint susceptibility testing using GC, DST, and proteose agars, was performed on consecutive clinical isolates of non-penicillinase producing Neisseria gonorrhoeae to examine the feasibility of using such a system in a diagnostic laboratory. The incidence and level of resistance to penicillin and spectinomycin was also assessed. On DST medium 93 of 200 (46.5%) of isolates were of intermediate resistance to penicillin (MIC 0.12-0.5 mg/l) and 21 of 200 (10.5%) were resistant to penicillin (MIC greater than or equal to 1.0 mg/l). Ninety two of 200 (46%) of isolates had an MIC to spectinomycin of 32 mg/l on DST agar. Isolates seemed to be more resistant when tested on the two other media. The methods used in this study could be applied in a routine diagnostic laboratory for immediate clinical benefit and long term epidemiological studies. To enable direct comparisons to be made between populations at different centres, however, methods for gonococcal susceptibility testing need to be standardised.

Neisseria gonorrhoeae: a versatile pathogen.

Neisseria gonorrhoeae is one of the most important causes of sexually transmitted disease. We do not fully understand the pathogenesis of infection with this organism, although recent improvements in immunological and molecular techniques have brought us closer to an answer. These techniques are now also being used to detect and identify N gonorrhoeae and to analyse the epidemiology of gonorrhoea. Plasmid and chromosomal mediated antibiotic resistance increases the difficulty of controlling gonorrhoea. Resistant strains occur all over the world and new patterns of resistance are still emerging. A better understanding of gonococcal pathogenicity is necessary for the development of an effective vaccine. Despite work on pili and outer membrane proteins no vaccine yet exists. The control of gonorrhoea still depends on diagnosis, treatment, and epidemiological control, facilities that are not widely available in many of those parts of the world where gonorrhoea is a major problem.

Homology of cryptic plasmid of Neisseria gonorrhoeae with plasmids from Neisseria meningitidis and Neisseria lactamica.

DNA probe hybridisation was used to examine the relation between the cryptic plasmid from Neisseria gonorrhoeae and plasmids carried by pharyngeal isolates of Neisseria meningitidis and Neisseria lactamica. The complete gonococcal cryptic plasmid and HinfI derived digestion fragments subcloned into Escherichia coli were used to probe Southern blots of plasmid extracts. Homology was found to a plasmid of approximate molecular weight 4.5 kilobase pairs (Kb) but not to plasmids of less than 3.2 Kb or 6.5 Kb. Eleven of 16 strains of N meningitidis and two of six strains of N lactamica carried plasmids that showed strong hybridisation with the 4.2 Kb gonococcal plasmid. Hybridisation of plasmids from non-gonococcal species of neisseria with the gonococcal cryptic plasmid indicates that caution should be taken when using the cryptic plasmid as a diagnostic probe for gonorrhoea.

Enzyme-linked immunosorbent assay (ELISA) to detect antibodies in gonorrhea using whole cells.

The choice of an antigen that will adequately differentiate between infected and non-infected patients has been a problem in detecting gonococcal antibodies for diagnosis. We have used the sensitive technique of ELISA to test various serotypes of Neisseria gonorrhoeae for their suitability as antigens. Whole cells of each serotype were attached to polystyrene plates using poly-L-lysine, N gonorrhoeae, strain H1 type 1 was used to detect antibodies in patients with known clinical history and then as a standard to evaluate the ability of different serotypes to differentiate between infected and non-infected groups.

Plasmids in throat and genital isolates of meningococci.

Plasmids 1.6, 2.8, or greater than 40 megadaltons in size were found in one urethral and nine throat strains of meningococci. Throat meningococci are known to be heterogeneous in their aminopeptidase profiles. Their unexpected content of plasmids is further evidence of their difference from classic systemic strains. Although the 2.8 megadalton plasmid has some resemblance to the well known 2.6 megadalton gonococcal plasmid, restriction enzyme studies gave no evidence of identity. Possible sources of the plasmids are discussed.