Evaluation of the anatomical site distribution of chlamydia and gonorrhoea in men who have sex with men and in high-risk women by routine testing: cross-sectional study revealing missed opportunities for treatment strategies: Table 1

Sexually transmitted infections among at-risk women in Ecuador: implications for global prevalence and testing practices for STIs detected only at the anorectum in female sex workers

OBJECTIVES

Anorectal sexually transmitted infections (STIs) such as Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), present treatment challenges, potentially increase antibiotic resistance selection and if undetected may facilitate onward transmission. However, there are limited global prevalence data for anorectal STIs. We conducted a cross-sectional study to assess the prevalence and risk factors of non-viral genital and extragenital STIs in female sex workers (FSW) and female non-sex workers (NSW) in Ecuador.

METHODS

250 adult street and brothel FSWs and 250 NSWs, recruited from settlements in north-west Ecuador provided oropharyngeal and vulvo-vaginal swabs (VVS) as well as socio-demographic data. FSWs also provided anorectal swabs. PCR was used to detect CT, NG, Mycoplasma genitalium (MG) from all swabs and additionally Trichomonas vaginalis (TV) from VVS. Risk factors were analysed using logistic regression.

RESULTS

Prevalence of FSW vaginal, anorectal and oropharyngeal infection was 32.0% (95% CI 26.5% to 38.0%), 19.7% (95% CI 15.1% to 25.2%) and 3.2% (95% CI 1.6% to 6.2%), respectively, with most vaginal infections being TV (23.4%; 95% CI 18.5% to 29.2%). Overall FSW STI prevalence, at any anatomical site was 39.7% (95% CI 33.8% to 46.1%), with 12.1% (95% CI 8.5% to 16.9%) of infections detected only at the anorectum. Of all the CT and/or NG infections, 64.4% (95% CI 50.4% to 78.4%) were detected only at the anorectum. STI prevalence in NSWs in the vagina and oropharynx were 5.6% (95% CI 3.4% to 9.2%) and 0.8% (95% CI 0.2% to 2.9%), respectively, with most vaginal infections being MG (3.2%; 95% CI 1.6% to 6.2%). In multivariable analysis, risk factors among brothel-based FSWs for having an anorectal STI were vaginal CT, NG or MG (p<0.001), vaginal TV (p=0.029) and being 'in a relationship' (p=0.038).

CONCLUSIONS

High prevalence of CT and NG detected only at the anorectum in these FSWs indicate the possibility of missing significant infections if providing only genital testing and calls for greater research into the potential impact on global STI estimates if extragenital infections among at-risk women are not identified.

Anorectal Neisseria gonorrhoeae infections in women with and without reported anal sex and sex workers in sexual health centres in the Netherlands: a retrospective cohort study

BACKGROUND

Control of Neisseria gonorrhoeae infection (gonorrhoea) depends on effective testing strategies. Anorectal testing in women is often done on indication of anal sex; however, anorectal infections are seen with and without anal exposure, possibly caused by autoinoculation. This study aims to enhance understanding of anorectal infections in women, by identifying risk factors for anorectal diagnosis.

METHODS

In this retrospective cohort study we used national surveillance data from Dutch sexual health centres from Jan 1, 2016, to Dec 31, 2021. We included cisgender women having sex with men who were tested urogenitally and anorectally for gonorrhoea. Due to different testing policies, we identified three groups: women who had not reported recent anal sex (in the past 6 months), women who had reported recent anal sex, and sex workers. Extracted data for analyses included demographics, sexual behaviour, and diagnosis of a sexually transmitted infection (STI). Per group, multivariable models using Firth's penalised maximum likelihood logistic regression were constructed, identifying determinants of anorectal gonorrhoea among all women and among gonorrhoea-positive women only. Variables included in model construction were age, education level, migration background, number of partners, condom use, partner notification, STI symptoms, having a partner who has sex with men (MSM) or a migrant partner, previous STI test, anal sex, and chlamydia and gonorrhoea diagnoses per anatomical location.

FINDINGS

In total, 117 693 women were included: 43 757 women without reported recent anal sex, 51 728 women with reported recent anal sex, and 22 208 sex workers. In all three groups, around 2% of women were gonorrhoea positive, and 70% or more of women had an anorectal infection. The strongest determinant of anorectal gonorrhoea was a concurrent urogenital gonorrhoea diagnosis (adjusted odds ratios [aOR] 782 [95% CI 605-1018]) among women without reported recent anal sex (612 [490-768] among women with reported recent anal sex, and 464 [335-652] among sex workers). Among gonorrhoea-positive women, determinants of anorectal gonorrhoea were urogenital and anorectal chlamydia co-infection (aOR 2·03 [95% CI 1·38-3·02], for women without reported anal sex) and migration background (1·44 [1·02-2·06], for women with reported anal sex). Determinants among sex workers were condomless sex (2·43 [1·55-3·82]), anal sex (1·71 [1·10-2·66]), MSM or migrant partner (1·78 [1·13-2·79]), and urogenital and anorectal chlamydia co-infection (2·28 [1·11-5·14]).

INTERPRETATION

These findings support the possibility of an autoinoculation process from the urogenital to the anorectal location due to the very strong correlation between urogenital and anorectal gonorrhoea, and due to the similarity of results across all three groups. Current testing strategies could miss anorectal infections, which should be considered when developing gonorrhoea prevention and control guidelines.

FUNDING

None.

HIV pre-exposure prophylaxis and diagnoses of sexually transmitted infections - observational data from German checkpoints, 01/2019-08/2021

BACKGROUND

The impact of starting HIV pre-exposure prophylaxis (PrEP) on diagnoses of sexually transmitted infections (STI) remains unclear. We used data from German HIV/STI Checkpoints collected from 01/2019 to 08/2021 to determine the impact of PrEP use on syphilis, gonorrhoea and chlamydia diagnoses.

METHODS

We used self-reported data on demographics, sexual behaviour, testing and PrEP use, as well as lab-confirmed diagnoses from visits to HIV/STI Checkpoints in Germany. PrEP use was categorized as (1) never used; (2) intention to use; (3) former use; (4) current on-demand use; (5) daily use. In multivariate regression analyses (MRA) with gonorrhoea, chlamydia, and syphilis diagnoses as outcomes, we controlled for age, number of sexual partners, number of condomless anal intercourse (CAI) partners in the last six months, and testing recency.

RESULTS

For the analysis, we included 9,219 visits for gonorrhoea and chlamydia testing and 11,199 visits for syphilis testing conducted at checkpoints from 01/2019 to 08/2021. MRA identified age (aOR 0.98; 95%CI 0.97-0.99), number of sexual partners in the past six months (aOR 4.90; 95%CI 2.53-9.52 for 11 + partners), and use of chemsex substances (aOR 1.62; 95%CI 1.32-2.00) as risk factors for gonorrhoea, while age (aOR 0.99; 95%CI 0.98-1.00), number of CAI partners (aOR 3.19; 95%CI 2.32-4.41 for 5 + partners), partner sorting (aOR 1.30; 95%CI 1.09-1.54), and use of chemsex substances (aOR 1.29; 95%CI 1.05-1.59) were risk factors for chlamydia infections. For syphilis, the number of CAI partners (aOR 3.19; 95%CI 1.60-6.34 for 5 + partners) was found to be the only significant risk factor. There was a strong association between PrEP use and the number of sexual partners (≤ 5 vs.>5: aOR 3.58; 95%CI 2.15-5.97 for daily PrEP use), the number of CAI partners in the past six months (≤ 1 vs.>1: aOR 3.70; 95%CI 2.15-6.37 for daily PrEP use), and the number of STI tests performed (suggesting higher testing frequency). Both outcomes were also related to partner sorting, chemsex, and selling sex.

CONCLUSIONS

Checkpoint visits reporting current PrEP use or intention to start PrEP correlated with eligibility criteria for PrEP, i.e. high partner numbers, inconsistent condom use during anal intercourse, and use of chemsex drugs. Use of HIV-specific prevention methods such as HIV serosorting, PrEP sorting, and viral load sorting was reported more frequently. (Daily) PrEP use was an independent risk factor for a chlamydia diagnosis only.

Update on the Epidemiology, Screening, and Management of Chlamydia trachomatis Infection

Chlamydia trachomatis infection ("chlamydia") is the most commonly diagnosed bacterial sexually transmitted infection globally, occurring in the genitals (urethra or vagina/cervix), rectum, or pharynx. If left untreated in women, genital chlamydia can ascend into the upper genital tract causing pelvic inflammatory disease, increasing their risk for ectopic pregnancy, infertility, and chronic pelvic pain. In men, chlamydia can cause epididymitis and proctitis. However, chlamydia is asymptomatic in over 80% of cases. This article provides an update on the epidemiology, natural history, and clinical manifestations of chlamydia in adults and discusses the current approaches to its management and control policy.

Controversies and evidence on Chlamydia testing and treatment in asymptomatic women and men who have sex with men: a narrative review

Background

Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted infection (STI) worldwide. CT is mainly asymptomatic. Test-and-treat strategies are widely implemented to prevent transmission and complications. Strategies are not without controversy in asymptomatic women and men who have sex with men (MSM). Concerns are emerging to test and treat asymptomatic persons for urogenital CT (‘Controversy 1’) and pharyngeal or rectal CT (‘Controversy 2’), whereby testing symptomatic persons is not under debate. Opposed views in CT treatment involve using azithromycin versus doxycycline (‘Controversy 3’). The objective of this review is to provide coverage of these public health and clinical controversies by reviewing the current scientific evidence.

Methods

A literature search was performed using PubMed for relevant publications between 2018 and September 2021, and iterative retrieval of additional relevant publications.

Results

Controversy 1. In women, the majority of asymptomatic CT are at the urogenital site, and detections mostly include viable CT. CT easily transmits to a partner and potentially also between the vaginal and rectal areas; the clinical impact of urogenital CT is established, although risks for adverse outcomes are uncertain. Wide-scale testing in asymptomatic women has not resulted in reduced prevalence. In MSM, evidence for the clinical impact of asymptomatic urogenital CT is lacking. Controversy 2. Rectal CT is common in women diagnosed with urogenital CT, but the clinical impact of asymptomatic rectal CT is uncertain. In MSM, rectal CT is common, and most CT infections are at the rectal site, yet the risk of longer term complications is unknown. In both sexes, pharyngeal CT is uncommon and has no documented clinical impact. Controversy 3. In the treatment of rectal CT, doxycycline has superior effectiveness to azithromycin. Evidence has also accumulated on the harms of test-and-treat strategies.

Conclusions

Current practices vary widely, from widescale test-and-treat approaches to more individual patient- and partner-level case management. Choosing which asymptomatic people to test at what anatomic site, and whether to test or not, requires an urgent (re-)definition of the goals of testing and treating asymptomatic persons. Treatment guidelines are shifting toward universal doxycycline use, and clinical practice now faces the challenge of implementation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07171-2.

Test-and-treat is a key strategy in the control of Chlamydia trachomatis (CT). We discuss recent controversies and present scientific evidence regarding urogenital, rectal, and pharyngeal CT test-and-treat strategies in women and in men who have sex with men (MSM). This should inform best practices for the prevention and management of the most common bacterial sexually transmitted infection (STI) worldwide.

A Novel Flow Cytometric Approach for the Quantification and Quality Control of Chlamydia trachomatis Preparations

Chlamydia trachomatis is an obligate intracellular pathogenic bacterium with a biphasic developmental cycle manifesting two distinct morphological forms: infectious elementary bodies (EBs) and replicative intracellular reticulate bodies (RBs). Current standard protocols for quantification of the isolates assess infectious particles by titering inclusion-forming units, using permissive cell lines, and analyzing via immunofluorescence. Enumeration of total particle counts is achieved by counting labeled EBs/RBs using a fluorescence microscope. Both methods are time-consuming with a high risk of observer bias. For a better assessment of C. trachomatis preparations, we developed a simple and time-saving flow cytometry-based workflow for quantifying small particles, such as EBs with a size of 300 nm. This included optimization of gain and threshold settings with the addition of a neutral density filter for small-particle discrimination. The nucleic acid dye SYBR® Green I (SGI) was used together with propidium iodide and 5(6)-carboxyfluorescein diacetate to enumerate and discriminate between live and dead bacteria. We found no significant differences between the direct particle count of SGI-stained C. trachomatis preparations measured by microscopy or flow cytometry (p > 0.05). Furthermore, we completed our results by introducing a cell culture-independent viability assay. Our measurements showed very good reproducibility and comparability to the existing state-of-the-art methods, indicating that the evaluation of C. trachomatis preparations by flow cytometry is a fast and reliable method. Thus, our method facilitates an improved assessment of the quality of C. trachomatis preparations for downstream applications.

Oral, Vaginal and Anal Sexual Practices among Heterosexual Males and Females Attending a Sexual Health Clinic: A Cross-Sectional Survey in Melbourne, Australia

Sex practices among heterosexuals are not well studied. We aimed to explore sexual practices among heterosexuals attending a sexual health clinic. This cross-sectional survey was conducted at Melbourne Sexual Health Centre between March and April 2019. Data were collected on kissing, oral sex (fellatio or cunnilingus), vaginal sex, anal sex and rimming in the previous 3 months. Univariable and multivariable logistic regression analyses were performed to examine the associations between engaging in anal sex and other sex practices. There were 709 participants (333 men; 376 women) who were eligible and completed the survey (response rate was 24.6%). In the past 3 months, most participants had had vaginal sex (n = 677; 95.5%), with a mean of 3.0 (standard deviation (SD): 3.9) vaginal sex partners, and half reported engaging in condomless vaginal sex in the past 3 months (n = 358; 50.1%). A total of 135 (19.0%) participants had had anal sex, with a mean of 1.3 (SD: 1.0) anal sex partners, with 63.5% (n = 94) engaging in any condomless anal sex in the past 3 months. Most participants (n = 637, 89.8%) had received oral sex in the past 3 months; this proportion did not differ by age group or gender. Women (n = 351, 93.4%) were more likely to perform oral sex than men (n = 275; 82.6% men) (p < 0.001) and to have received rimming (26.6% women vs. 12.6% men; p < 0.001). Men were more likely to have performed rimming (25.5% men vs. 9.3% women; p < 0.001). After adjusting for age, number of partners and sexual practice, anal sex was associated with being ≥35 years (adjusted odds ratio (aOR): 2.3; 95% CI: 1.2–4.2), receiving rimming (aOR: 3.8; 95% CI: 2.4–6.0) and performing rimming (aOR: 2.8; 95% CI: 1.8–4.6). Rimming and anal sex are practiced by one-fifth or more of heterosexuals. Older heterosexuals were more likely to engage in anal sex and to perform rimming. Future research should consider the benefits of testing extragenital sites where appropriate.

Gonorrhoea: a systematic review of prevalence reporting globally

BACKGROUND

The World Health Organization (WHO) recommends periodic gonorrhoea prevalence assessments in the general population or proxies thereof (including pregnant women, women attending family planning clinics, military recruits, and men undergoing employment physicals for example) and in population groups at increased risk, including men-who-have-sex-with-men (MSM) and sex workers.

METHOD

We evaluated reported prevalence data, including estimates from proxy general population samples to reflect the WHO recommendations. We describe the outcomes from the general population country-by-country and extend previous reviews to include MSM, sex workers, and extragenital infections.

RESULT AND CONCLUSION

In our systematic search, 2015 titles were reviewed (January 2010-April 2019) and 174 full-text publications were included. National, population-based prevalence data were identified in only four countries (the United States of America, the United Kingdom, Peru, New Caledonia) and local population-based estimates were reported in areas within five countries (China, South Africa, Brazil, Benin, and Malawi). The remaining studies identified only reported test positivity from non-probability, proxy general population samples. Due to the diversity of the reviewed studies, detailed comparison across studies was not possible. In MSM, data were identified from 64 studies in 25 countries. Rectal infection rates were generally higher than urogenital or pharyngeal infection rates, where extragenital testing was conducted. Data on sex workers were identified from 41 studies in 23 countries; rates in female sex workers were high. Current prevalence monitoring was shown to be highly suboptimal worldwide. Serial prevalence monitoring of critical epidemiological variables, and guidelines to optimize prevalence study conduct and reporting beyond antenatal settings are recommended.

Pharyngeal Chlamydia trachomatis in Men Who Have Sex With Men (MSM) in The Netherlands: A Large Retrospective Cohort Study

Pharyngeal Chlamydia trachomatis (CT) was diagnosed in 1.2% and pharyngeal-only CT in 0.5% of routinely universally tested men who have sex with men (MSM). In these 3-anatomic-site tested MSM, pharyngeal-only CT comprised 4.8% of all CT. The low positivity of pharyngeal-only CT indicates low public health impact of pharyngeal CT.

Increased risk of subsequent chlamydia infection among women not tested at the anorectal anatomical location

BACKGROUND

Universal anorectal testing for Chlamydia trachomatis (chlamydia) among women is not recommended in many countries, while anorectal chlamydia infections are common. Missed anorectal infections might cause sequelae at the genital site if autoinoculation from the anorectum is possible, but evidence is limited. This study investigates the association between potentially missed anorectal infections and subsequent genital chlamydia infections in women, using not being tested at the anorectal site as a proxy for having a potentially missed anorectal infection.

METHODS

We included all women with a repeat chlamydia test within 1 year (with at least a genital test) from the Dutch sexual health centre surveillance between 2014 and 2019. Multilevel logistic regression analyses were used to identify determinants of genital chlamydia infection at the repeat test, with anorectal testing at the previous chlamydia test as the main determinant.

RESULTS

A total of 40 217 women were included in the analyses, of whom 15.4% tested chlamydia-positive genitally at their second test. Not being tested anorectally at the first test was an independent risk factor for genital chlamydia infection at the repeat test (adjusted OR 1.24, 95% CI 1.15 to 1.33). This association was in the same range as most other significant risk factors in the model: low education level, no condom use, STI symptoms and previous STI diagnosis. Young age (<20 years) (2.67, 2.39-2.98) and those who received partner notification (3.11, 2.91-3.31) showed stronger associations. The findings were robust; correcting for interactions and a sensitivity analysis stratifying by chlamydia infection at first visit did not show significant differences in the adjusted OR of not being tested anorectally at first test.

CONCLUSION

The results are suggestive of an autoinoculation process from the anorectal to the genital anatomical site in women. To enhance chlamydia control, future studies on the role of extragenital testing and autoinoculation in chlamydia transmission are needed.

What Is the Optimal Testing Strategy for Oropharyngeal Neisseria gonorrhoeae in Men Who Have Sex With Men? Comparing Selective Testing Versus Routine Universal Testing From Dutch Sexually Transmitted Infection Clinic Data (2008-2017)

BACKGROUND

Most oropharyngeal Neisseria gonorrhoeae infections are asymptomatic, and many infections remain undetected, creating a reservoir for ongoing transmission and potential drug resistance. It is unclear what the optimal testing policy is in men who have sex with men (MSM), as routine universal testing data are lacking.

METHODS

Surveillance data from all Dutch sexually transmitted infection (STI) clinics between 2008 and 2017 were used (N = 271 242 consultations). Oropharyngeal testing policy was defined as routine universal testing when ≥85% of consultations included oropharyngeal testing or as selective testing (<85% tested). Independent risk factors for oropharyngeal N. gonorrhoeae were assessed among MSM routinely universally screened using backward multivariable logistic regression analyses.

RESULTS

Routine universal testing was performed in 90% (238 619/265 127) of consultations. Prevalence was higher using routine universal testing (5.5%; 95% CI, 5.4-5.6; 12 769/233 476) than with selective testing (4.7%; 95% CI, 4.4-5.0; 799/17 079; P < .001). Proportions of oropharyngeal-only infections were 55% and 47%, respectively. Independent risk factors were age <31 years (OR, 2.1; 95% CI, 1.9-2.3), age 31-43 years (OR, 1.7; 95% CI, 1.6-1.9, compared with >43 years), being notified for any STI (OR, 2.0; 95% CI, 1.9-2.1), concurrent urogenital N. gonorrhoeae (OR, 2.4; 95% CI, 2.1-2.7), and concurrent anorectal N. gonorrhoeae (OR, 11.4; 95% CI, 10.6-12.3). When using any of the risk factors age, notified, or oral sex as testing indicators, 98.4% (81 022/82 332) of MSM would be tested, finding 99.5% (4814/4838) of infections.

CONCLUSIONS

Routine universal testing detected more oropharyngeal N. gonorrhoeae infections than selective testing, of which more than half would be oropharyngeal only. Using independent risk factors as testing indicator is not specific. Therefore, routine universal oropharyngeal testing in MSM is feasible and warranted, as currently advised in most guidelines.

Performance of 4 Molecular Assays for Detection of Chlamydia and Gonorrhea in a Sample of Human Immunodeficiency Virus-Positive Men Who Have Sex With Men

BACKGROUND

Nucleic acid amplification testing (NAAT) is the preferred method to detect Chlamydia trachomatis and Neisseria gonorrhoeae, but information regarding performance of currently available assays is needed. This study evaluated the performance of the Aptima Combo 2, GeneXpert, cobas4800, and ProbeTec Q (CTQ/GCQ) to detect chlamydia and gonorrhea in pharyngeal, rectal, and urine specimen.

METHODS

Adult male patients seen at an urban human immunodeficiency virus clinic in Birmingham, Alabama who reported sex with men (men who have sex with men) and no antibiotic use in the past 30 days were enrolled between November 2014 and December 2016. Following a baseline survey, rectal and initial void urine specimens were self-collected. A composite infection standard was used, where 1 assay was compared with 3 others to determine sensitivity and specificity estimates for rectal and urine samples. Two pharyngeal samples were clinician-collected for chlamydia and gonorrhea testing and both had to be positive to be considered a true positive.

RESULTS

Among the 181 men enrolled into the study, 15.5% and 7.2% had at least 1 positive chlamydia and gonorrhea result at any site, respectively. Among all 4 assays, chlamydia sensitivity rates ranged from 82% to 96% among rectal samples. Rectal gonorrhea sensitivity estimates ranged from 67% to 99%. The GCQ assay was less sensitive in detecting rectal gonorrhea compared with the other assays (P = 0.02).

CONCLUSIONS

More than 80% of chlamydia and gonorrhea infections would have been missed with urine-only screening, highlighting the importance in using NAATs to detect chlamydia and gonorrhea infections among men who have sex with men.

Update your "sore throat" differential list: A case report and discussion of oral chlamydia

ABSTRACT

There has been an exponential increase in sexually transmitted infections (STIs) in the United States, causing the Centers for Disease Control and Prevention to declare an epidemic. Current evidence demonstrates that extragenital STIs of the oropharynx and rectum are often asymptomatic and may not be associated with concurrent positive urogenital infections. As a result, these infections are often missed in primary care. Furthermore, guidelines only recommend extragenital site testing in men who have sex with men, excluding oropharyngeal chlamydia, despite evidence that extragenital STIs are occurring in other high-risk populations as well. A case report is provided to enhance primary health care providers' knowledge of extragenital STIs and promote early recognition and testing to improve patient outcomes.

Routine universal testing versus selective or incidental testing for oropharyngeal Neisseria gonorrhoeae in women in the Netherlands: a retrospective cohort study

BACKGROUND

Women are not routinely tested for oropharyngeal Neisseria gonorrhoeae. At present, selective testing based on sexual behaviour or risk groups is advocated by international guidelines. Many oropharyngeal infections are asymptomatic and thus remain undetected, establishing a reservoir for ongoing transmission. Data on effectiveness of routine testing are scarce, thus we aimed to assess the optimal testing strategy for oropharyngeal N gonorrhoeae in women.

METHODS

In this retrospective cohort study, we used surveillance data obtained from all sexually transmitted infection (STI) clinics in the Netherlands between Jan 1, 2008, and Dec 31, 2017. We collected consultation-level data, and individual-level patient data from 2016 onwards, on sociodemographic characteristics, sexual behaviour in the past 6 months, self-reported symptoms, and STI diagnoses. We compared the prevalence of oropharyngeal N gonorrhoeae between women who attended clinics that offered routine universal testing (defined as >85% of women tested per clinic-year) and women who attended clinics that offered selective testing (defined as 5-85% of women tested per clinic-year) or incidental testing (<5% of women tested per clinic-year). We calculated the number of infections missed by selective testing by extrapolating prevalence for the routine universal testing group to that of weighted and unweighted samples of all selectively tested women. We used multivariable generalised estimating equations to identify independent risk factors for oropharyngeal N gonorrhoeae to identify the optimal selective testing strategy.

FINDINGS

554 266 consultations with at least one N gonorrhoeae test were recorded, of which 545 750 consultations (including repeat visits) were included in the analyses. Of 545 750 consultations, routine universal testing was used in 57 359 (10·5%), selective testing in 444 283 (81·4%), and incidental testing in 44 108 (8·1%). The prevalence of oropharyngeal N gonorrhoeae was 1·4% (95% CI 1·3-1·5; 703 of 50 962 consultations) in the routine testing group compared with 1·4% (1·3-1·5; 1858 of 132 276) in the selective testing group (p=0·68) and 2·8% (1·9-3·9; 30 of 1088) in the incidental testing group (p<0·0001). The prevalence of oropharyngeal-only infections was 47·7% (335 of 703 women) in the routine testing group, 53·3% (991 of 1858) in the selective testing group, and 60·0% (18 of 30) in the incidental testing group. Selective testing would have missed an estimated 4363 (70%; 95% CI 69-71) of all 6221 oropharyngeal N gonorrhoeae infections. Independent risk factors for oropharyngeal N gonorrhoeae were being notified for any STI (adjusted odds ratio 2·1, 95% CI 1·5-3·0), reporting sex work (4·0, 2·3-6·7), and having concurrent genital (51·5, 34·1-77·7) or anorectal (2·6, 1·4-4·8) N gonorrhoeae. Selective testing of women notified for any STI, or who reported sex work, would have led to 5418 (27·8%) of 19 455 women being tested and would have identified 119 (55·6%) of 214 oropharyngeal N gonorrhoeae infections.

INTERPRETATION

Selective testing potentially misses more than two-thirds of oropharyngeal N gonorrhoeae infections in women, of whom half have oropharyngeal infections without concurrent genital or anorectal infections. Using independent risk factors for oropharyngeal infection to guide testing is a minimal testing strategy. Routine universal testing is the optimum scenario to detect the majority of infections. However, future studies are needed to assess the cost-effectiveness of routine testing and its effect on antimicrobial resistance.

FUNDING

Public Health Service South Limburg.

Background review for the '2020 European guideline for the diagnosis and treatment of gonorrhoea in adults'

Gonorrhoea is a major public health concern globally. Increasing incidence and sporadic ceftriaxone-resistant cases, including treatment failures, are growing concerns. The 2020 European gonorrhoea guideline provides up-to-date evidence-based guidance regarding the diagnosis and treatment of gonorrhoea. The updates and recommendations emphasize significantly increasing gonorrhoea incidence; broad indications for increased testing with validated and quality-assured nucleic acid amplification tests (NAATs) and culture; dual antimicrobial therapy including high-dose ceftriaxone and azithromycin (ceftriaxone 1 g plus azithromycin 2 g) OR ceftriaxone 1 g monotherapy (ONLY in well-controlled settings, see guideline for details) for uncomplicated gonorrhoea when the antimicrobial susceptibility is unknown; recommendation of test of cure (TOC) in all gonorrhoea cases to ensure eradication of infection and identify resistance; and enhanced surveillance of treatment failures when recommended treatment regimens have been used. Improvements in access to appropriate testing, test performance, diagnostics, antimicrobial susceptibility surveillance and treatment, and follow-up of gonorrhoea patients are essential in controlling gonorrhoea and to mitigate the emergence and/or spread of ceftriaxone resistance and multidrug-resistant and extensively drug-resistant gonorrhoea. This review provides the detailed background, evidence base and discussions, for the 2020 European guideline for the diagnosis and treatment of gonorrhoea in adults (Unemo M, et al. Int J STD AIDS. 2020).

2020 European guideline for the diagnosis and treatment of gonorrhoea in adults

Gonorrhoea is a major public health concern globally. Increasing incidence and sporadic ceftriaxone-resistant cases, including treatment failures, are growing concerns. The 2020 European gonorrhoea guideline provides up-to-date evidence-based guidance regarding the diagnosis and treatment of gonorrhoea. The updates and recommendations emphasize significantly increasing gonorrhoea incidence; broad indications for increased testing with validated and quality-assured nucleic acid amplification tests and culture; dual antimicrobial therapy including high-dose ceftriaxone and azithromycin (ceftriaxone 1 g plus azithromycin 2 g) OR ceftriaxone 1 g monotherapy (ONLY in well-controlled settings, see guideline for details) for uncomplicated gonorrhoea when the antimicrobial susceptibility is unknown; recommendation of test of cure (TOC) in all gonorrhoea cases to ensure eradication of infection and identify resistance; and enhanced surveillance of treatment failures when recommended treatment regimens have been used. Improvements in access to appropriate testing, test performance, diagnostics, antimicrobial susceptibility surveillance and treatment, and follow-up of gonorrhoea patients are essential in controlling gonorrhoea and to mitigate the emergence and/or spread of ceftriaxone resistance and multidrug-resistant and extensively drug-resistant gonorrhoea. For detailed background, evidence base and discussions, see the background review for the present 2020 European guideline for the diagnosis and treatment of gonorrhoea in adults (Unemo M, et al. Int J STD AIDS. 2020).

Extragenital Screening for Chlamydia and Gonorrhea Among Adolescents and Young Adults at a Sexual Health Clinic

OBJECTIVE

To increase screening rates for oropharyngeal and rectal (extragenital) chlamydia and gonorrhea infections among adolescents and young adults by 20% and for 90% of nurses to demonstrate a change in behavior and knowledge surrounding extragenital screening.

DESIGN

A pre- and posttest design to evaluate nurse knowledge and the percentage of extragenital chlamydia and gonorrhea screenings completed before and after a 2-month intervention period.

SETTING

Reproductive health clinic for adolescents and young adults up to age 25 years in the Twin Cities metropolitan area of Minnesota.

PARTICIPANTS

Four registered nurses who provide direct client care at the identified sexual and reproductive health clinic.

INTERVENTION/MEASUREMENTS

We implemented an education session for four staff nurses, a standardized sexual history taking tool, and protocols for obtaining oropharyngeal and rectal specimens. We measured extragenital chlamydia and gonorrhea screening rates, as well as knowledge and behavior change among registered nurses.

RESULTS

Data came from records for 623 individuals who were deemed at risk for extragenital chlamydia and gonorrhea infection. Extragenital chlamydia and gonorrhea screening rates increased by more than 700% from before to after the intervention. Five out of nine (55.6%) extragenital chlamydia and gonorrhea infections diagnosed would have been missed with urogenital screening alone. One hundred percent of nurses demonstrated an increase in their knowledge of the 5 P's of sexual health (Partners, Practices, Protection from sexually transmitted infections, Past history of STIs, and Prevention of pregnancy) to conduct a risk assessment, the eligibility criteria for extragenital testing, and the actual collection processes of pharyngeal and rectal swabs.

CONCLUSION

Use of evidence-based recommendations and a collaborative team facilitated a more consistent approach to the assessment and diagnosis of extragenital chlamydia and gonorrhea infections. Generalizability is limited to the project site; however, this process could be implemented in other clinics to determine if similar results can be achieved.

Contribution of general practitioners and sexual health centres to sexually transmitted infection consultations in five Dutch regions using laboratory data of Chlamydia trachomatis testing

Effective sexually transmitted infection (STI) control requires opportunities for appropriate testing, counselling and treatment. In the Netherlands, people may attend general practitioners (GPs) and sexual health centres (SHCs; also known as STI clinics) for STI consultations. We assessed the contribution of GPs and SHCs to STI consultations in five Dutch regions with different urbanization levels, using data of urogenital Chlamydia trachomatis (CT) testing. Data (2011–2016) were retrieved from laboratories, aggregated by gender and age group (15–24 and 25–64 years). Results show that test rates and GP contribution varied widely between regions. GP contribution decreased over time in Amsterdam (60–48%), Twente (79–61%), Maastricht (60–50%) and Northeast-Netherlands (82–77%), but not in Rotterdam (65–67%). Decreases resulted from increases in SHC test rates and slight decreases in GP test rates. GPs performed more tests for women and those aged 25–64 years compared to SHCs (relative risks ranging from 1.49 to 4.76 and 1.58 to 7.43, respectively). The average yearly urogenital CT positivity rate was 9.2% at GPs and 10.7% at SHCs. Overall, GPs accounted for most STI consultations, yet SHC contribution increased. Continued focus on good quality STI care at GPs is essential, as increasing demands for care can not be entirely covered by SHCs.

Reduced sensitivity from pooled urine, pharyngeal and rectal specimens when using a molecular assay for the detection of chlamydia and gonorrhoea near the point of care

Background The aim of this study was to compare the performance of pooled self-collected urogenital, pharyngeal and anorectal specimens to that of individual specimen results for the molecular detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) near the point of care (POC) for diagnostic sensitivity.

METHODS

Clients (mostly men who have sex with men) attending an urban community testing service and three sex-on-premises venues in Brisbane, Australia, were offered CT and NG testing by trained lay providers. Participants provided three self-collected specimens (urine, pharyngeal and rectal) for testing by GeneXpert (Cepheid, Sunnyvale, CA, USA). If any of the individual specimens from a participant were positive, all three specimens were pooled and retested.

RESULTS

Of the 388 participants who provided three individual anatomical specimens, 76 (19.6%) were found to be positive for CT and/or NG at one or more sites. The pooling approach failed to detect five CT rectal and four NG pharyngeal infections. The overall performance (sensitivity) of the pooling approach compared with individual specimen testing and Cohen's κ were 90.0% and 0.86 respectively for CT and 89.7% and 0.89 respectively for NG.

CONCLUSIONS

Reduced sensitivity was observed when using pooled specimens for the detection of CT and NG using GeneXpert near the POC, similar to results reported in laboratory-based CT and NG pooling studies. These data suggest specimen pooling is feasible near to the POC, potentially saving time and costs when screening at-risk populations for CT and NG. Our data also suggest a reduction in pooled urine could improve overall test sensitivity.

Factors associated with anorectal Chlamydia trachomatis or Neisseria gonorrhoeae test positivity in women: a systematic review and meta-analysis

OBJECTIVES

There has been considerable discussion about anorectal Chlamydia trachomatis (CT) in women, with some calling for anorectal CT screening, but little about anorectal Neisseria gonorrhoeae (NG). Given that urogenital NG is more strongly associated with pelvic inflammatory disease, this is an evidence gap. This systematic review and meta-analysis investigates the associations between anorectal CT in women and CT positivity at other sites (urogenital/oropharyngeal) and with anal intercourse, and compares these with anorectal NG within the same study populations.

METHODS

Electronic databases were searched for English-language studies published to October 2018 using the following terms: ("Chlamydia" OR "Chlamydia trachomatis") AND (("anal" OR "rect*" OR "anorect*") OR ("extra?genital" OR "multi?site")). Studies were included if anorectal NG data were available. Random-effects meta-analyses calculated pooled estimates; heterogeneity was investigated using meta-regression.

RESULTS

25 studies were eligible. Anorectal CT positivity ranged from 0% to 17.5%, with a summary estimate of 8.0% (95% CI 7.0 to 9.1; I2=88.5%). Anorectal NG positivity ranged from 0% to 17.0%, with a summary estimate of 2.1% (95% CI 1.6 to 2.8; I2=92.7%). The association between urogenital and anorectal positivity was stronger for NG than CT (summary prevalence ratio (PR)=89.3 (95% CI 53.1 to 150.3; I2=80.1%), PR=32.2 (95% CI 25.6 to 40.7; I2=70.3%), respectively), and between oropharyngeal and anorectal positivity it was stronger for NG than CT (PR=34.8 (95% CI 10.2 to 118.2; I2=89.9%), PR=8.8 (95% CI 6.8 to 11.5; I2=58.1%), respectively). Anal intercourse was associated with anorectal NG (PR=4.3; 95% CI 2.2 to 8.6; I2=0.0%) but not with anorectal CT (PR=1.0; 95% CI 0.7 to 1.4; I2=0.0%).

CONCLUSIONS

Anorectal CT is more common than anorectal NG, but anorectal NG is more strongly associated with anal intercourse, urogenital and oropharyngeal NG, suggesting that ongoing discussion about anorectal CT should also include NG. Longitudinal data are required to further understanding of the aetiology of anorectal STIs and assess whether anorectal screening is needed in women.

TRIAL REGISTRATION NUMBER

CRD42df017080188.

Correlations of chlamydia and gonorrhoea among pharyngeal, rectal and urethral sites among Thai men who have sex with men: multicentre community-led test and treat cohort in Thailand

OBJECTIVE

Routine screening for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections in sexually exposed anatomical sites may be challenging in resource-limited settings. The objective of this study was to determine the proportion of missed CT/NG diagnoses if a single anatomical site screening was performed among men who have sex with men (MSM) by examining the pattern of anatomical sites of CT/NG infections.

METHODS

Thai MSM were enrolled to the community-led test and treat cohort. Screening for CT/NG infections was performed from pharyngeal swab, rectal swab and urine using nucleic acid amplification testing. The correlations of CT/NG among the three anatomical sites were analysed.

RESULTS

Among 1610 MSM included in the analysis, 21.7% had CT and 15.5% had NG infection at any anatomical site. Among those tested negative for CT or NG infection at either pharyngeal, rectal or urethral site, 8%-19% had CT infection and 7%-12% had NG infection at the remaining two sites. Of the total 349 CT infections, 85.9%, 30.6% and 67.8% would have been missed if only pharyngeal, rectal or urethral screening was performed, respectively. Of the total 249 NG infection, 55.7%, 39.6% and 77.4% would have been missed if only pharyngeal, rectal or urethral screening was performed, respectively. The majority of each anatomical site of CT/NG infection was isolated to their respective site, with rectal site having the highest proportion of isolation: 78.9% of rectal CT and 62.7% of rectal NG infection.

CONCLUSIONS

A high proportion of CT/NG infections would be missed if single anatomical site screening was performed among MSM. All-site screening is highly recommended, but if not feasible, rectal screening provides the highest yield of CT/NG diagnoses. Effort in lowering the cost of the CT/NG screening test or developing affordable molecular technologies for CT/NG detection is needed for MSM in resource-limited settings.

TRIAL REGISTRATION NUMBER

NCT03580512; Results.

Screening for Chlamydia trachomatis and Neisseria gonorrhoeae Infections in Men Who Have Sex With Men: Diagnostic Accuracy of Nucleic Acid Amplification Test on Pooled Urine, Anorectal, and Pharyngeal Specimens

Neisseria gonorrhoeae and Chlamydia trachomatis screening was performed in a cohort of 100 men who have sex with men. A nucleic acid amplification test on a pooled sample of first-pass urine, pharyngeal, and anorectal specimens was compared with results on nonpooled samples. Despite an excellent agreement (Cohen κ, 0.932), pooling specimens reduced test sensitivity to 89.5%.

Sexually transmitted infections: Need for extragenital screening

Extragenital infections can occur concurrently with simultaneous urogenital infections. Extragenital sites are believed to serve as hidden reservoirs and play a critical role in their transmission. The etiological relationship of the most widespread Sexually transmitted diseases (STD) pathogen to reproductive tract has long been established, but the distribution to extragenital sites appears to be infrequent and its correlation with the sexual practice still requires to be investigated. Optimal-screening strategies for extragenital infections are largely unknown. However, there is a lack of data on clinical outcomes and optimal treatment regimens for rectal and pharyngeal extragenital infections. Further studies are needed in settings other than reproductive health and STD clinics, especially in primary care clinics and resource-limited settings.

A Population-Based Study to Compare Treatment Outcomes Among Women With Urogenital Chlamydial Infection in Washington State, 1992 to 2015

BACKGROUND

United States guidelines recommend azithromycin or doxycycline for chlamydia (Chlamydia trachomatis [CT]) treatment. These therapies are similarly efficacious for urogenital infections when outcomes are measured 7 to 42 days after treatment, although doxycycline may be superior for rectal infections. Some investigators have suggested that persistent rectal infections may lead to autoinfection of the urogenital tract, potentially resulting in higher rates of recurrent infection in azithromycin-treated women.

METHODS

We used Washington State surveillance data to identify women 14 years or older with urogenital CT (1992-2015) treated with azithromycin or doxycycline. We defined persistent/recurrent CT as a repeat positive CT test result 14 to 180 days after treatment of the initial infection. We used log binomial regression to estimate the adjusted relative risk (aRR) of persistent/recurrent infection associated with treatment with azithromycin versus doxycycline.

RESULTS

From 1992 to 2015, there were 268,596 reported cases of urogenital CT, including 168,301 (63%) who received azithromycin and 66,432 (25%) who received doxycycline. The risk of persistent/recurrent urogenital CT was 6.7% and 4.7% in azithromycin- and doxycycline-treated cases, respectively (P < 0.001). Adjusting for age, race/ethnicity, year, pregnancy status, jurisdiction reporting, reason for examination, and gonorrhea coinfection, azithromycin-treated women were significantly more likely to have persistent/recurrent urogenital CT than doxycycline-treated women (aRR, 1.24; 95% confidence interval [CI], 1.19-1.30). Adjusting the retesting window to 21 to 180 days (aRR, 1.24; 95% CI, 1.19-1.30) and 28 to 180 days (aRR, 1.25; 95% CI, 1.19-1.30) did not alter our primary findings.

CONCLUSIONS

Persistent/recurrent urogenital CT may be more common among women treated with azithromycin than with doxycycline. The reason for this difference is uncertain and is an important area of future investigation.

Clinical diagnostic and therapeutic aspects of 221 consecutive anorectal Chlamydia trachomatis and Neisseria gonorrhoeae sexually transmitted infections among men who have sex with men

OBJECTIVES

Proctitis caused by Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are known as sexually transmitted infections (STI). This study describes their clinical, diagnostic and therapeutic aspects.

METHODS

Between 01/2013-03/2015, all MSM consulting for proctitis at proctology Institute-Saint-Joseph's Hospital, Paris, were included. Demographic, past-medical history, STI status and medical treatment were collected. Detection of CT/NG was performed by Transcription-Mediated Amplification (TMA) and antimicrobial susceptibilities for Ng by agar diffusion method.

RESULTS

On 441 rectal samples collected, 221 (50.1%) were positive: 109 Ct (49.3%), 70 Ng (31.7%), 42 positive for both etiologies (19%). Among Ng infections, no resistance was detected to azithromycin and ceftriaxone. However, 84 strains (43.2%) were resistant to fluoroquinolones. More than one episode was diagnosed for 10 (5.1%) and 12 (6.2%) patients with CT and NG infections respectively. Anal abscesses were found for 27 (13.9%) patients, and 14 (7.2%) of them underwent surgery for anal fistula.

CONCLUSIONS

The prevalence of CT/NG anorectal infections described is high on symptomatic patients, and a significant level of abscess was reported. These results confirm the interest of the association of recommended antibiotics excluding quinolones. Prospective studies would be relevant on complicated forms of anorectal infections.

High Proportion of Anorectal Chlamydia trachomatis and Neisseria gonorrhoeae After Routine Universal Urogenital and Anorectal Screening in Women Visiting the Sexually Transmitted Infection Clinic

Background.

Testing on indication of self-reported anal sex or symptoms is used to manage anorectal Chlamydia trachomatis (chlamydia) and Neisseria gonorrhoeae (gonorrhea) infections in women. Little is known about the impact of another testing strategy, routine universal anorectal screening with respect to chlamydia and gonorrhea prevalence and risk factors.

Methods.

All women (n = 1012) aged ≥16 years attending our sexually transmitted infection clinic in 2015 were offered routine universal screening. In total, 19.5% (n = 185) of women had an indication (reported anal sex or symptoms), 72.5% (n = 689) did not have an indication, and 8.0% (n = 76) had missing information on indication. Logistic regression analyses were used to identify determinants associated with anorectal chlamydia and gonorrhea.

Results.

Of all women who visited our clinic, 94% (n = 950) participated in the study. Overall anorectal chlamydia/gonorrhea positivity was 13.4% (n = 127)/1.3% (n = 12). Self-reported anal sex and anal symptoms were independently associated with anorectal gonorrhea (odds ratios [ORs], 3.3 [95% confidence interval {CI}, 1.01-10.7] and 14.5 [95% CI, 2.8-75.0], respectively), but not with anorectal chlamydia. Of all anorectal chlamydia/gonorrhea cases, 72% (n = 92)/33% (n = 4) were diagnosed in women without an indication, of which 19% (n = 19)/0% (n = 0) were anorectal only. For women with missing indication, this was 7% (n = 9)/8% (n = 1) and 44% (n = 4)/100% (n = 1).

Conclusions.

Anorectal screening in women without an indication is feasible and highly acceptable. Selective testing on indication could be an appropriate control strategy for anorectal gonorrhea, as few infections would be missed. In contrast, selective testing is a suboptimal control strategy for anorectal chlamydia, as we found a high prevalence in women both with and without indication for anorectal testing, along with a substantial amount of anorectal-only infections.

Sexually transmitted infections: challenges ahead

WHO estimated that nearly 1 million people become infected every day with any of four curable sexually transmitted infections (STIs): chlamydia, gonorrhoea, syphilis, and trichomoniasis. Despite their high global incidence, STIs remain a neglected area of research. In this Commission, we have prioritised five areas that represent particular challenges in STI treatment and control. Chlamydia remains the most commonly diagnosed bacterial STI in high-income countries despite widespread testing recommendations, sensitive and specific non-invasive testing techniques, and cheap effective therapy. We discuss the challenges for chlamydia control and evidence to support a shift from the current focus on infection-based screening to improved management of diagnosed cases and of chlamydial morbidity, such as pelvic inflammatory disease. The emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is globally recognised. We review current and potential future control and treatment strategies, with a focus on novel antimicrobials. Bacterial vaginosis is the most common vaginal disorder in women, but current treatments are associated with frequent recurrence. Recurrence after treatment might relate to evidence that suggests sexual transmission is integral to the pathogenesis of bacterial vaginosis, which has substantial implications for the development of effective management approaches. STIs disproportionately affect low-income and middle-income countries. We review strategies for case management, focusing on point-of-care tests that hold considerable potential for improving STI control. Lastly, STIs in men who have sex with men have increased since the late 1990s. We discuss the contribution of new biomedical HIV prevention strategies and risk compensation. Overall, this Commission aims to enhance the understanding of some of the key challenges facing the field of STIs, and outlines new approaches to improve the clinical management of STIs and public health.

Multidrug-resistant gonorrhea: A research and development roadmap to discover new medicines

Emilie Alirol and colleagues discuss the development of new treatments for gonorrhea.

Incidence of repeat testing and diagnoses of Chlamydia trachomatis and Neisseria gonorrhoea in swingers, homosexual and heterosexual men and women at two large Dutch STI clinics, 2006-2013

OBJECTIVE

Swingers, that is, heterosexuals who as a couple have sex with others, including group sex and bisexual behaviour, are an older-aged risk group for STIs. Here, we report on their repeat testing (reattendance) and STI yield compared with other heterosexuals and men who have sex with men (MSM, homosexual men) at two Dutch STI clinics.

METHODS

Swingers are routinely (since 2006, South Limburg, registration-completeness: 99%) or partially (since 2010, Amsterdam, registration-completeness: 20%) included in the clinic patient registries. Data (retrospective cohort) are analysed to assess incidence (per 100 person-years (PY)) of reattendance and STI (Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (NG)) and associated factors calculating HRs.

RESULTS

In South Limburg 7714 and in Amsterdam 2070 swinger consultations were identified. Since 2010, swingers' incidence of reattendance was 48-57/100 PY. Incidence was lower in MSM (30-39/100 PY, HR 0.56; 95% CI 0.51 to 0.61, South Limburg; HR 0.88; 95% CI 0.80 to 0.96, Amsterdam), heterosexual men (8-14/100 PY, HR 0.16; 95% CI 0.15 to 0.17, South Limburg; HR 0.33; 95% CI 0.30 to 0.36, Amsterdam) and women (13-20/100 PY, HR 0.56; 95% CI 0.51 to 0.61, South Limburg; HR 0.46; 95% CI 0.42 to 0.51, Amsterdam). Swingers' STI incidence at reattendance was 11-12/100 PY. Incidence was similar in heterosexual men (14-15/100 PY; HR 1.19; 95% CI 0.90 to 1.57, South Limburg; HR 1.20; 95% CI 0.91 to 1.59, Amsterdam) and women (12-14/100 PY; HR 1.14; 95% CI 0.88 to 1.49, South Limburg; HR 0.98; 95% CI 0.74 to 1.29, Amsterdam) and higher in MSM (18-22/100 PY; HR 1.59; 95% CI 1.19 to 2.12, South Limburg; HR 1.80; 95% CI 1.36 to 2.37, Amsterdam). Risk factors for STI incidence were partner-notified (contact-tracing), symptoms and previous STI. Swingers' positivity at any clinic attendance was 3-4% for NG (ie, higher than other heterosexuals) and 6-8% for CT (ie, lower than heterosexuals overall but higher than older heterosexuals).

CONCLUSIONS

Systematic identification reveals that swingers are part of the normal STI clinic populations. They frequently repeat test yet are likely under-recognised in clinics which not routinely ask about swinging. Given swingers' notable STI rates, usage of services is warranted, although use may be restricted, that is, to those with an STI risk factor (as did Dutch clinics). As swingers have dense sexual networks, enhancing contact-tracing may have high impact.

Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature

In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM), and men who have sex only with women (MSW), including distribution by anatomical site. Among women, prevalence was found to be 0.6–35.8% for rectal gonorrhea (median reported prevalence 1.9%), 0–29.6% for pharyngeal gonorrhea (median 2.1%), 2.0–77.3% for rectal chlamydia (median 8.7%), and 0.2–3.2% for pharyngeal chlamydia (median 1.7%). Among MSM, prevalence was found to be 0.2–24.0% for rectal gonorrhea (median 5.9%), 0.5–16.5% for pharyngeal gonorrhea (median 4.6%), 2.1–23.0% for rectal chlamydia (median 8.9%), and 0–3.6% for pharyngeal chlamydia (median 1.7%). Among MSW, the prevalence was found to be 0–5.7% for rectal gonorrhea (median 3.4%), 0.4–15.5% for pharyngeal gonorrhea (median 2.2%), 0–11.8% for rectal chlamydia (median 7.7%), and 0–22.0% for pharyngeal chlamydia (median 1.6%). Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.

Recorded gonorrhoea rates in Denmark, 1900-2010: the impact of clinical testing activity and laboratory diagnostic procedures

OBJECTIVES

Assessment of the relations between recorded gonorrhoea rates and clinical testing activity and disposable diagnostic tests.

METHODS

In Denmark, two sources of information on the epidemiology of gonorrhoea are available: (1) a mandatory clinical notification system (since 1867) comprising summary information about geographic distribution, season, age group and gender; in 1994, more detailed anonymous individualised epidemiological information was included; (2) a voluntary countrywide laboratory surveillance system for culture-confirmed cases (since 1957) comprising information about patient's age and gender, infected anatomical sites and medical setting attended.

RESULTS

Both surveillance systems showed marked simultaneous changes in gonorrhoea rates, although periodically considerable under-reporting or under-diagnosing was demonstrated. The annual incidence of notified cases peaked in 1919 (474/100,000), in 1944 (583/100,000) and in 1972 (344/100,000). Since 1995, the incidence has been at a low endemic level (1.5-10/100,000) and the total male/female incidence ratios were from 3 to 7 times higher than previously recorded. Among approximately 2 million persons tested during 1974-1988 78,213 men and 63,143 women with culture-confirmed gonorrhoea were identified. During this period, pharyngeal sampling was performed in 36% of men and 25% of women with gonorrhoea; pharyngeal gonorrhoea was found in 10% and 16%, respectively; 40% and 30% of these patients had no concomitant urogenital gonorrhoea. Among men with gonorrhoea, 34% were sampled from the rectum; 9% had rectal gonorrhoea, among whom the rectum was the only infected site in 67%.

CONCLUSIONS

Crucial factors for case finding are clinical sampling tradition and appropriate laboratory diagnostic facilities. When case finding is insufficient, a reservoir of asymptomatic rectal or pharyngeal gonorrhoea remains unrecognised.

Background review for the '2015 European guideline on the management of Chlamydia trachomatis infections'

SummaryChlamydia trachomatis infections are major public health concerns globally. Of particular grave concern is that the majority of persons with anogenital Chlamydia trachomatis infections are asymptomatic and accordingly not aware of their infection, and this silent infection can subsequently result in severe reproductive tract complications and sequelae. The current review paper provides all background, evidence base and discussions for the 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, et al. Int J STD AIDS 2015). Comprehensive information and recommendations are included regarding the diagnosis, treatment and prevention of anogenital, pharyngeal and conjunctival Chlamydia trachomatis infections in European countries. However, Chlamydia trachomatis also causes the eye infection trachoma, which is not a sexually transmitted infection. The 2015 European Chlamydia trachomatis guideline provides up-to-date guidance regarding broader indications for testing and treatment of Chlamydia trachomatis infections; clearer recommendation of using validated nucleic acid amplification tests only for diagnosis; advice on (repeated) Chlamydia trachomatis testing; recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection and recommendations to identify, verify and report Chlamydia trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of Chlamydia trachomatis patients are crucial to control its spread.

2015 European guideline on the management of Chlamydia trachomatis infections

Chlamydia trachomatis infections, which most frequently are asymptomatic, are major public health concerns globally. The 2015 European C. trachomatis guideline provides: up-to-date guidance regarding broader indications for testing and treatment of C. trachomatis infections; a clearer recommendation of using exclusively-validated nucleic acid amplification tests for diagnosis; advice on (repeated) C. trachomatis testing; the recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection; and recommendations to identify, verify and report C. trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of C. trachomatis patients are crucial to control its spread. For detailed background, evidence base and discussions, see the background review for the present 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, et al. Int J STD AIDS. 2015).

What is needed to guide testing for anorectal and pharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae in women and men? Evidence and opinion

Background

Anorectal and pharyngeal infections with Chlamydia trachomatis (CT) and Neisseria gonorrheae (NG) are commonly observed in men who have sex with men (MSM). There is increasing evidence that such infections at extra-genital sites are also common in women. In both sexes, these infections are largely overlooked as they are not routinely tested for in regular care. Testing based on sexual behavior or symptoms would only detect half of these extra-genital infections. This paper elucidates the differences and similarities between women and MSM, regarding the epidemiology of extra-genital CT and NG. It discusses the clinical and public health impact of untested extra-genital infections, how this may impact management strategies, and thereby identifies key research areas.

Discussion

Extra-genital CT is as common in women as it is in MSM; NG in women is as common at their extra-genital sites as it is at their genital sites. The substantial numbers of extra-genital CT and NG being missed in women and MSM indicate a need to test and treat more patients and perhaps different choices in treatment and partner management strategies. Doing so will likely contribute to reduced morbidity and transmission in both sexes. However, in our opinion, it is clear that there are several knowledge gaps in understanding the clinical and public health impact of extra-genital CT and NG. Key research areas that need to be addressed concern associated morbidity (anorectal and reproductive morbidity due to extra-genital infections), ‘the best’ management strategies, including testing and treatment for extra-genital CT, extra-genital treatment resistance, transmission probabilities between partners and between anatomic sites in a woman, and impact on transmission of other infections. Data are also lacking on cost-effectiveness of pharyngeal testing, and of NG testing and anorectal CT testing in women. Gaps in the management of extra-genital CT and NG may also apply for other STIs, such Mycoplasma genitalium.

Summary

Current management strategies, including testing, to address extra-genital CT and NG in both sexes are suboptimal. Comparative data on several identified key themes in women and MSM are lacking and urgently needed to guide better management of extra-genital infections.

2015 UK national guideline for the management of infection with Chlamydia trachomatis

This guideline offers recommendations on the diagnostic tests, treatment regimens and health promotion principles needed for the effective management of Chlamydia trachomatis genital infection. It covers the management of the initial presentation, as well the prevention of transmission and future infection. The guideline is aimed at individuals aged 16 years and older presenting to healthcare professionals working in departments offering Level 3 care in sexually transmitted infections management within the UK. However, the principles of the recommendations should be adopted across all levels, using local care pathways where appropriate.

Prevalence of and Factors Associated with Rectal-Only Chlamydia and Gonorrhoea in Women and in Men Who Have Sex with Men

BACKGROUND

Both anorectal Chlamydia trachomatis (CT) and Neisseria gonorrhoea (NG) can occur as a rectal-only infection or concurrently with simultaneous urogenital infection with the same pathogen. Characterising the target groups in which rectal-only infections occur may improve the efficacy of screening practices.

METHODS

We analysed data from two Dutch outpatient sexually transmitted infection (STI) clinics between 2011 and 2012. We included all men who have sex with men (MSM) (n = 9549) and women (n = 11113), ≥18 years, who had been tested for anorectal and urogenital CT and/or NG (either as a result of reporting anal sex/symptoms or via routine universal testing). Factors associated with rectal-only CT and NG infections were assessed using univariable and multivariable logistic regression.

RESULTS

In MSM, anorectal CT prevalence was 9.8% (693/7094), anorectal NG prevalence was 4.2% (397/9534). In women this was 9.5% overall (439/4597) and 0.9% (96/10972) respectively. Anorectal CT prevalence among women who were routinely universally tested was 10.4% (20/192), for selective testing this was 9.5% (419/4405) (p = 0.68). Anorectal NG infections were not detected among women who were routinely universally tested (p = 0.19). Among CT or NG positive MSM, rectal-only CT infections were found in 85.9% (595/693), for NG this was 85.6% (340/397) respectively. In positive women these figures were 22.1% (97/439)for CT and 20.8% (20/96) for NG, respectively. In MSM, independent factors associated with rectal-only CT were: being a sex worker (OR0.4,CI0.2-1.0), exclusively having sex with men (OR3.4,CI1.7-6.8), and absence of urogenital symptoms (OR0.2,CI0.2-0.4). In women, these factors were: older age (OR2.3, CI1.3-4.0) and non-Western nationality (OR1.8, CI1.0-3.5). Factors associated with rectal-only NG in MSM were: having been warned for STIs by an (ex) partner (OR2.9,CI1.1-7.5), oropharyngeal NG infection (OR2.4,CI1.0-5.3), and absence of urogenital symptoms (OR0.02,CI0.01-0.04), while in women no significant factors were identified.

CONCLUSIONS

The prevalence of anorectal CT and NG was substantial in MSM and prevalence of anorectal CT was also substantial in women. Anorectal infections occurred mostly as rectal-only infections in MSM and mostly concurrent with other infections in women. Given the lack of useful indicators for rectal-only infections, selective screening based on a priori patient characteristics will have low discriminatory power both in relation to MSM and women.

Neisseria gonorrhoeae and Chlamydia trachomatis among women reporting extragenital exposures

BACKGROUND

The Centers for Disease Control and Prevention recommends pharyngeal screening of Neisseria gonorrhoeae (GC) and rectal screening of GC and Chlamydia trachomatis (CT) in HIV-infected and at-risk men who have sex with men (MSM). There are currently no recommendations to routinely screen women at extragenital sites. We define the prevalence of extragenital GC and CT in women attending 2 urban sexually transmitted disease clinics in Baltimore City and compare it with the prevalence of extragenital infections in MSM and men who have sex with women.

METHODS

All patients who reported extragenital exposures in the preceding 3 months, who presented for care between June 1, 2011, and May 31, 2013, and who were tested for GC and CT using nucleic acid amplification tests at all sites of exposure were included in the analyses. We used logistic regression models to identify risk factors for extragenital infections.

RESULTS

A total of 10,389 patients were included in this analysis (88% African American; mean age, 29 years; 42% women; 7% MSM; 2.5% HIV infected). The prevalence estimates of any extragenital GC and CT were as follows: 2.4% GC and 3.7% CT in women, 2.6% GC and 1.6% CT in men who have sex with women, and 18.9% GC and 11.8% CT in MSM. Among women, 30.3% of GC infections and 13.8% of CT infections would have been missed with urogenital-only testing. Unlike MSM, age ≤ 18 years was the strongest predictor of extragenital infections in women.

CONCLUSIONS

Although the prevalence of extragenital gonorrhea and chlamydia is highest in MSM, a significant number of GC and CT infections in young women would be missed with genital-only testing. Cost-effectiveness analyses are needed to help inform national guidelines on extragenital screening in young women.

Who tests whom? A comprehensive overview of Chlamydia trachomatis test practices in a Dutch region among different STI care providers for urogenital, anorectal and oropharyngeal sites in young people: a cross-sectional study

OBJECTIVES

To evaluate and compare Chlamydia trachomatis (CT) diagnostic test practices of different sexually transmitted infection (STI) care providers in 16-29 year olds from one defined geographic Dutch region (280,000 inhabitants). Both number and proportion of positive CT tests (ie, test positivity) were assessed, and factors associated with these outcomes.

METHODS

Data on laboratory testing and diagnosis of urogenital, anorectal and oropharyngeal CT between 2006 and 2010 were retrieved from general practitioners (GPs), gynaecologists, an STI clinic and a population-based chlamydia screening programme. Multivariable regression analyses explored associations between age, sex, test year, socio-economic status (SES) and STI care provider and the outcomes being the number of tests and test positivity.

RESULTS

Overall, 22,831 tests were performed (1868 positive; 8.2%). Extragenital (ie, anorectal and oropharyngeal) tests accounted for 4% of all tests (7.5% positive) and were almost exclusively (99%) performed by the STI clinic. STI clinics tested most men (37.2% of all tested men), whereas GPs tested most women (29.9% of all tested women). GPs and STI clinics accounted for 73.3% (1326/1808) of urogenital CT diagnoses. In women, the number of tests increased with age, whereas test positivity decreased for all STI care providers. Lower SES was associated with higher test positivity in GP and gynaecology patients.

CONCLUSIONS

STI clinics performed most CT tests in men, whereas GPs performed most CT tests in women. GPs and STI clinics accounted for the majority of positives. Extragenital CT testing is rarely performed outside the STI clinic and needs to be promoted, especially in men who have sex with men.

Anorectal Chlamydia trachomatis Load Is Similar in Men Who Have Sex with Men and Women Reporting Anal Sex

BACKGROUND

Anorectal Chlamydia trachomatis (chlamydia) is frequently diagnosed in men who have sex with men (MSM) and in women, but it is unknown whether these infections are comparable in clinical impact and transmission potential. Quantifying bacterial load and identifying determinants associated with high bacterial load could provide more insight.

METHODS

We selected a convenience sample of MSM who reported anal sex (n = 90) and women with concurrent urogenital/anorectal chlamydia who reported anal sex (n = 51) or did not report anal sex (n = 61) from the South Limburg Public Health Service's STI unit. Bacterial load (Chlamydia/ml) was quantified for all samples and log transformed for analyses. Samples with an unquantifiable human leukocyte antigen (n = 9) were excluded from analyses, as they were deemed inadequately sampled.

RESULTS

The mean log anorectal chlamydia load (3.50) was similar for MSM and women who reported having anal sex (3.80, P = 0.21). The anorectal chlamydia load was significantly higher in these groups than in women who did not report having anal sex (2.76, P = 0.001). Detectable load values ranged from 1.81-6.32 chlamydia/ml for MSM, 1.74-7.33 chlamydia/ml for women who reported having anal sex and 1.84-6.31 chlamydia/ml for women who did not report having anal sex. Symptoms and several other determinants were not associated with anorectal chlamydia load.

CONCLUSIONS

Women who did not report anal sex had lower anorectal loads, but they were within a similar range to the other two groups. Anorectal chlamydia load was comparable between MSM and women who reported anal sex, suggesting similar transmission potential.

Successful Combination of Nucleic Acid Amplification Test Diagnostics and Targeted Deferred Neisseria gonorrhoeae Culture

Nucleic acid amplification tests (NAATs) are recommended for the diagnosis of N. gonorrhoeae infections because of their superior sensitivity. Increasing NAAT use causes a decline in crucial antimicrobial resistance (AMR) surveillance data, which rely on culture. We analyzed the suitability of the ESwab system for NAAT diagnostics and deferred targeted N. gonorrhoeae culture to allow selective and efficient culture based on NAAT results. We included patients visiting the STI Clinic Amsterdam, The Netherlands, in 2013. Patient characteristics and urogenital and rectal samples for direct N. gonorrhoeae culture, standard NAAT, and ESwab were collected. Standard NAAT and NAAT on ESwab samples were performed using the Aptima Combo 2 assay for N. gonorrhoeae and C. trachomatis. Two deferred N. gonorrhoeae cultures were performed on NAAT-positive ESwab samples after storage at 4°C for 1 to 3 days. We included 2,452 samples from 1,893 patients. In the standard NAAT, 107 samples were N. gonorrhoeae positive and 284 were C. trachomatis positive. The sensitivities of NAAT on ESwab samples were 83% (95% confidence interval [CI], 75 to 90%) and 87% (95% CI, 82 to 90%), respectively. ESwab samples were available for 98 of the gonorrhea-positive samples. Of these, 82% were positive in direct culture and 69% and 56% were positive in the 1st and 2nd deferred cultures, respectively (median storage times, 27 and 48 h, respectively). Deferred culture was more often successful in urogenital samples or when the patient had symptoms at the sampling site. Deferred N. gonorrhoeae culture of stored ESwab samples is feasible and enables AMR surveillance. To limit the loss in NAAT sensitivity, we recommend obtaining separate samples for NAAT and deferred culture.

High prevalence of rectal gonorrhea and Chlamydia infection in women attending a sexually transmitted disease clinic

BACKGROUND

Testing women for urogenital Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) is common in sexually transmitted disease (STD) clinics. However, women may not be routinely tested for rectal GC/CT. This may lead to missed infections in women reporting anal intercourse (AI).

METHODS

This was a retrospective review of all women who underwent rectal GC/CT testing from August 2012 to June 2013 at an STD clinic in Columbus, Ohio. All women who reported AI in the last year had a rectal swab collected for GC/CT nucleic acid amplification testing (n=331). Using log-binomial regression models, we computed unadjusted and adjusted associations for demographic and behavioral factors associated with rectal GC/CT infection.

RESULTS

Participants (n=331) were 47% African-American, with median age of 29 years. Prevalence of rectal GC was 6%, rectal CT was 13%, and either rectal infection was 19%. Prevalence of urogenital GC and CT was 7% and 13% respectively. Among women with rectal GC, 14% tested negative for urogenital GC. Similarly, 14% of women with rectal CT tested negative for urogenital CT. In unadjusted analyses, there was increased rectal GC prevalence among women reporting sex in the last year with an injection drug user, with a person exchanging sex for drugs or money, with anonymous partners, and while intoxicated/high on alcohol or illicit drugs. After multivariable adjustment, no significant associations persisted, but a trend of increased rectal GC prevalence was observed for women <26 years of age (p=0.06) and those reporting sex while intoxicated/high on alcohol or drugs (p=0.05). For rectal CT, only age <26 years was associated with prevalent infection in unadjusted models; this association strengthened after multivariable adjustment (prevalence ratio: 6.03; 95% confidence interval: 2.29-15.90).

CONCLUSION

Nearly one in five women who reported AI in the last year had rectal GC or CT infection. Urogenital testing alone would have missed 14% of rectal infections. Standardized guidelines would increase rectal GC/CT testing in women and help detect missed infections.

Screening for Asymptomatic Extragenital Gonorrhea and Chlamydia in Men Who Have Sex with Men: Significance, Recommendations, and Options for Overcoming Barriers to Testing

Men who have sex with men (MSM) have a disproportionately greater risk than other populations of acquiring Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC), the two most commonly reported notifiable diseases in the United States according to the Centers for Disease Control and Prevention (CDC). The presence of either of these diseases is a significant risk factor for the acquisition and transmission of human immunodeficiency virus (HIV). Recent studies have shown that significant rates of asymptomatic GC and CT infection are found at the extragenital oropharygeal and rectal sites in MSM, with or without concurrent urogenital infection. However, extragenital sites are not being routinely screened and, thus, many asymptomatic GC and CT infections at the oropharyngeal and rectal sites may go undiagnosed. This review will begin with the current evidence-based screening recommendations for extragenital GC and CT in MSM. This will be followed by recently reported extragenital GC and CT infection rates in asymptomatic MSM, and a discussion of the risks and potential implications of undiagnosed extragenital GC and CT infections. Finally, a discussion on the frequency of, and potential barriers to, screening will be presented with a summary of potential interventions for increasing screening frequency found in the literature. The scope of this review will focus primarily on U.S. recommendations, infection rates, and screening frequencies, with the inclusion of relevant international recommendations and studies for comparative and illustrative purposes.

Risk factors for HIV and STI diagnosis in a community-based HIV/STI testing and counselling site for men having sex with men (MSM) in a large German city in 2011-2012

Background

In recent years community-based voluntary counselling and testing sites (CB-VCT) for men having sex with men (MSM) have been established in larger cities in Germany to offer more opportunities for HIV testing. Increasingly, CB-VCTs also offer testing for other bacterial sexually transmitted infections. In Hamburg, tests in CB-VCTs are offered free and anonymously. Data on demographics and sexual risk behaviours are collected with a paper questionnaire.

Methods

Questionnaire data from the MSM CB-VCT in Hamburg were linked with serological test results for HIV and syphilis, and with rectal and pharyngeal swab results for gonorrhoea and chlamydia. MSM were defined as males reporting male sex partners. CB-VCT clients were characterized demographically, and associations between sexual behaviour variables and diagnosis of HIV and sexually transmitted infections (STI) were analysed by bivariate and multivariate logistic regression analysis.

Results

Among the male clients of the CB-VCT in 2011–2012 who were tested for HIV or any STI 1476 reported male sex partners. Unprotected anal intercourse (UAI) was reported as reason for testing by 61% of the clients. Forty-one of 1413 clients testing for HIV were tested positive (2.9%). Twenty-four of 1380 clients testing for syphilis required treatment (1.7%). Tests for simultaneous detection of N. gonorrhoea and Chlamydia trachomatis were conducted on 882 pharyngeal and 642 rectal swabs, revealing 58 (=6.6%) pharyngeal and 71 (=11.1%) rectal infections with one or both pathogens. In multivariate logistic regression analysis number of partners, UAI (OR=2.42) and relying on visual impression when selecting sex partners (OR = 2.92) were associated with increased risks for diagnosis of syphilis or a rectal STI. Syphilis or rectal STI diagnosis (OR=4.52) were associated with increased risk for HIV diagnosis.

Conclusions

The MSM CB-VCT in Hamburg reaches clients at high risk for HIV and STIs. The diagnosis of syphilis or a rectal STI was associated with increased odds of testing positive for HIV. Due to the high prevalence of curable bacterial STI among clients and because syphilis and rectal bacterial STI may facilitate HIV transmission, MSM asking for HIV tests in CB-VCTs should also be offered tests for other bacterial STIs.

The added value of chlamydia screening between 2008-2010 in reaching young people in addition to chlamydia testing in regular care; an observational study

Background

Internet-based Chlamydia Screening Implementation (chlamydia screening programme) was introduced in the Netherlands in 2008-2010 to detect and treat asymptomatic infections and to limit ongoing transmission through annual testing and treatment of Chlamydia trachomatis in young people (16-29 years). This population-based screening may be less effective when addressing individuals who are already covered by regular care, instead of addressing a hidden key population without chlamydia testing experience in regular care. This study had two aims: (1) to assess the rate and determinants of newly reached (i.e. not previously tested in 2006-2010) participants in the chlamydia screening programme, and (2) to assess the chlamydia positivity in these newly reached participants.

Methods

This observational matching study included all chlamydia tests performed in subjects aged 16-29 years in eastern South Limburg in the Netherlands (population 16-29 years:41,000) between 2006-2010. Testing was conducted during the systematic chlamydia screening programme (2008-2010), at a sexually transmitted infections clinic (STI clinic), by general practitioners (GPs), and by medical specialists as reported by the medical laboratory serving the region. Data were matched between testing services on individual level. The study population included all participants who were tested at least once for chlamydia by the chlamydia screening programme. Participants were included at their first chlamydia screening participation.

Results

In the chlamydia screening programme, 80.7% (4298/5323) of participants were newly reached, others were previously tested by the STI clinic (5.7%, n=304), GPs (6.2%, n=328), medical specialists (3.5%, n=187) or a combination of providers (3.9%, n=206). Chlamydia prevalence was similar in newly reached participants (4.8%, 204/4298) and participants previously tested (4.5%, 46/1025, P=0.82). Independent determinants for being a newly reached participant were male gender (men OR 2.9; 95% CI 2.5-3.4) and young age <21 years (versus 25-29 years OR 1.8; 95% CI 1.5-2.2).

Conclusions

The majority of the chlamydia screening programme participants have not been tested by regular care, and show similar chlamydia prevalence as those previously tested. Thereby population-based chlamydia screening adds to the existing regular care by testing young individuals hidden to current regular care.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0612-2) contains supplementary material, which is available to authorized users.