Scenarios of future mpox outbreaks among men who have sex with men: a modelling study based on cross-sectional seroprevalence data from the Netherlands, 2022

BackgroundFollowing the 2022-2023 mpox outbreak, crucial knowledge gaps exist regarding orthopoxvirus-specific immunity in risk groups and its impact on future outbreaks.AimWe combined cross-sectional seroprevalence studies in two cities in the Netherlands with mathematical modelling to evaluate scenarios of future mpox outbreaks among men who have sex with men (MSM).MethodsSerum samples were obtained from 1,065 MSM attending Centres for Sexual Health (CSH) in Rotterdam or Amsterdam following the peak of the Dutch mpox outbreak and the introduction of vaccination. For MSM visiting the Rotterdam CSH, sera were linked to epidemiological and vaccination data. An in-house developed ELISA was used to detect vaccinia virus (VACV)-specific IgG. These observations were combined with published data on serial interval and vaccine effectiveness to inform a stochastic transmission model that estimates the risk of future mpox outbreaks.ResultsThe seroprevalence of VACV-specific antibodies was 45.4% and 47.1% in Rotterdam and Amsterdam, respectively. Transmission modelling showed that the impact of risk group vaccination on the original outbreak was likely small. However, assuming different scenarios, the number of mpox cases in a future outbreak would be markedly reduced because of vaccination. Simultaneously, the current level of immunity alone may not prevent future outbreaks. Maintaining a short time-to-diagnosis is a key component of any strategy to prevent new outbreaks.ConclusionOur findings indicate a reduced likelihood of large future mpox outbreaks among MSM in the Netherlands under current conditions, but emphasise the importance of maintaining population immunity, diagnostic capacities and disease awareness.

The roles of the general practitioner and sexual health centre in HIV testing: comparative insights and impact on HIV incidence rates in the Rotterdam area, the Netherlands - a cross-sectional population-based study

BACKGROUND

Access to HIV testing is crucial for detection, linkage to treatment, and prevention. In less urbanised areas, reliance on general practitioners (GPs) for HIV testing is probable, as sexual health centres (SHC) are mostly located within urbanised areas. Limited insight into individuals undergoing HIV testing stems from sparse standard registration of demographics at GPs. This cross-sectional study aims (1) to assess and compare HIV testing at the GP and SHC, and (2) to assess population- and provider-specific HIV incidence.

METHODS

Individual HIV testing data of GPs and SHC were linked to population register data (aged ≥ 15 years, Rotterdam area, 2015-2019). We reported the proportion HIV tested, and compared GP and SHC testing rates with negative binomial generalised additive models. Data on new HIV diagnoses (2015-2019) from the Dutch HIV Monitoring Foundation relative to the population were used to assess HIV incidence.

RESULTS

The overall proportion HIV tested was 1.14% for all residents, ranging from 0.41% for ≥ 40-year-olds to 4.70% for Antilleans. The GP testing rate was generally higher than the SHC testing rate with an overall rate ratio (RR) of 1.61 (95% CI: 1.56-1.65), but not for 15-24-year-olds (RR: 0.81, 95% CI: 0.74-0.88). Large differences in HIV testing rate (1.36 to 39.47 per 1,000 residents) and GP-SHC ratio (RR: 0.23 to 7.24) by geographical area were observed. The GPs' contribution in HIV testing was greater for GP in areas further away from the SHC. In general, population groups that are relatively often tested are also the groups with most diagnoses and highest incidence (e.g., men who have sex with men, non-western). The overall incidence was 10.55 per 100,000 residents, varying from 3.09 for heterosexual men/women to 24.04 for 25-29-year-olds.

CONCLUSIONS

GPs have a pivotal role in HIV testing in less urbanised areas further away from the SHC, and among some population groups. A relatively high incidence often follows relatively high testing rates. Opportunities to improve HIV testing have been found for migrants, lower-educated individuals, in areas less urbanised areas and further away from GP/SHC. Strategies include additional targeted testing, via for example SHC branch locations and outreach activities.

Evaluating the Added Value of Digital Contact Tracing Support Tools for Citizens: Framework Development

BACKGROUND

The COVID-19 pandemic revealed that with high infection rates, health services conducting contact tracing (CT) could become overburdened, leading to limited or incomplete CT. Digital CT support (DCTS) tools are designed to mimic traditional CT, by transferring a part of or all the tasks of CT into the hands of citizens. Besides saving time for health services, these tools may help to increase the number of contacts retrieved during the contact identification process, quantity and quality of contact details, and speed of the contact notification process. The added value of DCTS tools for CT is currently unknown.

OBJECTIVE

To help determine whether DCTS tools could improve the effectiveness of CT, this study aims to develop a framework for the comprehensive assessment of these tools.

METHODS

A framework containing evaluation topics, research questions, accompanying study designs, and methods was developed based on consultations with CT experts from municipal public health services and national public health authorities, complemented with scientific literature.

RESULTS

These efforts resulted in a framework aiming to assist with the assessment of the following aspects of CT: speed; comprehensiveness; effectiveness with regard to contact notification; positive case detection; potential workload reduction of public health professionals; demographics related to adoption and reach; and user experiences of public health professionals, index cases, and contacts.

CONCLUSIONS

This framework provides guidance for researchers and policy makers in designing their own evaluation studies, the findings of which can help determine how and the extent to which DCTS tools should be implemented as a CT strategy for future infectious disease outbreaks.

Testing for sexually transmitted infection: who and where? A data linkage study using population and provider data in the Rotterdam area, the Netherlands

BACKGROUND

In the Netherlands, insight into sexually transmitted infection (STI) testing and characteristics of those tested by general practitioners (GPs) and sexual health centres (SHC) is limited. This is partly due to lacking registration of socio-demographics at GPs. We aimed to fill this gap by linking different registers.

METHODS

Individual STI testing data of GPs and SHC were linked to population register data (aged ≥15 years, Rotterdam area, 2015-2019). We reported population-specific STI positivity, proportion STI tested, and GP-SHC testing rate comparison using negative binomial generalised additive models. Factors associated with STI testing were determined by the provider using logistic regression analyses with generalised estimating equations.

RESULTS

The proportion of STI tested was 2.8% for all residents and up to 9.8% for younger and defined migrant groups. STI positivity differed greatly by subgroup and provider (3.0-35.3%). Overall, GPs performed 3 times more STI tests than the SHC. The smallest difference in GP-SHC testing rate was for 20-24-year-olds (SHC key group). Younger age, non-western migratory background, lower household income, living more urbanised, and closer to a testing site were associated with STI testing by either GP or SHC. GPs and SHC partly test different groups: GPs test women and lower-educated more often, the SHC men and middle/higher educated.

CONCLUSIONS

This study highlights GPs' important role in STI testing. The GPs' role in the prevention, diagnosis, and treatment of STIs needs continued support and strengthening. Inter-professional exchange and collaboration between GP and SHC is warranted to reach vulnerable groups.

Online-Mediated HIV Pre-exposure Prophylaxis Care and Reduced Monitoring Frequency for Men Who Have Sex With Men: Protocol for a Randomized Controlled Noninferiority Trial (EZI-PrEP Study)

BACKGROUND

Daily and event-driven HIV pre-exposure prophylaxis (PrEP) with oral tenofovir-emtricitabine is highly effective to prevent HIV in men who have sex with men (MSM). PrEP care generally consists of in-clinic monitoring every 3 months that includes PrEP dispensing, counseling, and screening for HIV and sexually transmitted infections (STIs). However, the optimal frequency for monitoring remains undetermined. Attending a clinic every 3 months for monitoring may be a barrier for PrEP. Online-mediated PrEP care and reduced frequency of monitoring may lower this barrier.

OBJECTIVE

The primary objective of this study is to establish the noninferiority of online PrEP care (vs in-clinic care) and monitoring every 6 months (vs every 3 months). The secondary objectives are to (1) examine differences between PrEP care modalities regarding incidences of STIs, HIV infection, and hepatitis C virus infection; retention in PrEP care; intracellular tenofovir-diphosphate concentration; and satisfaction, usability, and acceptability of PrEP care modalities; and (2) evaluate associations of these study outcomes with sociodemographic, behavioral, and psychological characteristics.

METHODS

This study is a 2×2 factorial, 4-arm, open-label, multi-center, randomized, controlled, noninferiority trial. The 4 arms are (1) in-clinic monitoring every 3 months, (2) in-clinic monitoring every 6 months, (3) online monitoring every 3 months, and (4) online monitoring every 6 months. The primary outcome is a condomless anal sex act with a casual partner not covered or insufficiently covered by PrEP (ie, "unprotected act") as a proxy for HIV infection risk. Eligible individuals are MSM, and transgender and gender diverse people aged ≥18 years who are eligible for PrEP care at 1 of 4 participating sexual health centers in the Netherlands. The required sample size is 442 participants, and the planned observation time is 24 months. All study participants will receive access to a smartphone app, which contains a diary. Participants are requested to complete the diary on a daily basis during the first 18 months of participation. Participants will complete questionnaires at baseline and 6, 12, 18, and 24 months. Dried blood spots will be collected at 6 and 12 months for assessment of intracellular tenofovir-diphosphate concentration. Incidence rates of unprotected acts will be compared between the online and in-clinic arms, and between the 6-month and 3-month arms. Noninferiority will be concluded if the upper limit of the 2-sided 97.5% CI of the incidence rate ratio is <1.8.

RESULTS

The results of the main analysis are expected in 2024.

CONCLUSIONS

This trial will demonstrate whether online PrEP care and monitoring every 6 months is noninferior to standard PrEP care in terms of PrEP adherence. If noninferiority is established, these modalities may lower barriers for initiating and continuing PrEP use and potentially reduce the systemic burden for PrEP providers.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05093036; https://tinyurl.com/28b8ndvj.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51023.

HIV and syphilis testing for women and heterosexual men aged above 25 years in the Netherlands: possibilities for targeted testing at sexual health centres

OBJECTIVES

Targeted testing policy for HIV/syphilis at Dutch sexual health centres (SHCs) was evaluated for its efficiency in younger heterosexuals but not for heterosexuals ≥25 years. Currently, all older heterosexuals are tested for HIV/syphilis at SHCs. To explore possibilities for increased efficiency of testing in heterosexuals aged >25 years, this study aimed to identify determinants of HIV and syphilis diagnoses that could be used in targeted testing strategies.

DESIGN

An observational study using surveillance data from all Dutch SHC.

PARTICIPANTS

Women and heterosexual men aged >25 years visiting SHC between 2015 and 2021.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was HIV/syphilis diagnosis, determinants of a diagnosis were analysed. Based on these determinants and their applicability in SHC practice, different targeted testing scenarios were evaluated. For each scenario, the percentage of consultations involving HIV and syphilis testing and the total amount of missed HIV and syphilis diagnoses were calculated.

RESULTS

109 122 consultations were included among 75 718 individuals. The strongest determinants of HIV/syphilis diagnosis were HIV/syphilis-specific symptoms (adjusted OR (aOR) 34.9 (24.1-50.2)) and receiving partner notification (aOR 18.3 (13.2-25.2)), followed by low/middle education level (aOR 2.8 (2.0-4.0)), male sex (aOR 2.2 (1.6-3.0)) and age ≥30 years (aOR 1.8 (1.3-2.5)). When applying feasible determinants to targeted testing scenarios, HIV/syphilis testing would have been conducted in 54.5% of all consultations, missing 2 HIV and 3 syphilis diagnoses annually (13.4% and 11.4% of all diagnoses, respectively). In the scenario with the lowest number of missed HIV/syphilis diagnoses (0.3 HIV and 2 syphilis diagnoses annually), HIV/syphilis testing would have been conducted in 74.2% of all consultations.

CONCLUSIONS

In any targeted testing scenario studied, HIV and/or syphilis diagnoses would have been missed. This raises the question whether it is acceptable to put any of these scenarios into practice. This study contributes to a discussion about the impact of targeted testing policy.

Community-based HIV testing through a general health check event in a high HIV-prevalent multicultural area in Rotterdam, The Netherlands: a pilot study on feasibility and acceptance

BACKGROUND

HIV testing is crucial for finding the remaining cases in a declining HIV epidemic in The Netherlands; providing HIV testing in non-traditional settings may be warranted. We conducted a pilot study to determine the feasibility and acceptability of a community-based HIV testing (CBHT) approach with general health checks to improve HIV test uptake.

METHODS

CBHT's main conditions were low-threshold, free-of-charge, general health check, and HIV education. We interviewed 6 community leaders, 25 residents, and 12 professionals/volunteers from local organizations to outline these main conditions. Walk-in test events were piloted at community organizations, providing HIV testing along with body mass index (BMI), blood pressure, blood glucose screening, and HIV education (October 2019 to February 2020). Demographics, HIV testing history, risk perception, and sexual contact were collected via questionnaires. To evaluate the pilots' feasibility and acceptance, we utilized the RE-AIM framework and predefined goals, incorporating quantitative data from the test events and qualitative input from participants, organizations, and staff.

RESULTS

A total of 140 individuals participated (74% women, 85% non-Western, median age 49 years old). The number of participants during the seven 4-h test events ranged from 10 to 31. We tested 134 participants for HIV, and one was found positive (positivity 0.75%). Almost 90% of the participants were never tested or > 1 year ago, and 90% perceived no HIV risk. One-third of the participants had one or more abnormal test results on BMI, blood pressure, or blood glucose. The pilot was well-rated and accepted by all parties. The staff had concerns about waiting time, language problems, and privacy. Participants hardly indicated these concerns.

CONCLUSIONS

This CBHT approach is feasible, acceptable, and well-suited for testing not (recently) tested individuals and detecting new cases. Besides reducing HIV-associated stigma and increasing HIV test acceptance, offering multiple health tests may be appropriate as we frequently observed multiple health problems. Whether this laborious approach is sustainable in the micro-elimination of HIV and should be deployed on a large scale is questionable. CBHT like ours may be suitable as a supplement to more sustainable and cost-effective methods, e.g., proactive HIV testing by general practitioners and partner notification.

Area-based comparison of risk factors and testing rates to improve sexual health care access: cross-sectional population-based study in a Dutch multicultural area

OBJECTIVES

Areas with high sexually transmitted infection (STI) testing rates may not require additional strategies to improve testing. However, it may be necessary to intervene in areas with elevated STI risk, but with low STI testing rates. We aimed to compare STI-related risk profiles and STI testing rates by geographical area to determine areas for improvement of sexual healthcare access.

DESIGN

Cross-sectional population-based study.

SETTING

Greater Rotterdam area, the Netherlands (2015-2019).

PARTICIPANTS

All residents aged 15-45 years. Individual population-based register data were matched with laboratory-based STI testing data of general practitioners (GPs) and the only sexual health centre (SHC).

OUTCOME MEASURES

Postal code (PC) area-specific STI risk scores (based on age, migratory background, education level and urbanisation), STI testing rates and STI positivity.

RESULTS

The study area consists of approximately 500 000 residents aged 15-45 years. Strong spatial variation in STI testing, STI positivity and STI risk was observed. PC area testing rate ranged from 5.2 to 114.9 tests per 1000 residents. Three PC clusters were identified based on STI risk and testing rate: (1) high-high; (2) high-low; (3) low, independently of testing rate. Clusters 1 and 2 had comparable STI-related risk and STI positivity, but the testing rate differed greatly (75.8 vs 33.2 per 1000 residents). Multivariable logistic regression analysis with generalised estimating equation was used to compare residents in cluster 1 and cluster 2. Compared with cluster 1, residents in cluster 2 more often did not have a migratory background, lived in less urbanised areas with higher median household income, and more distant from both GP and SHC.

CONCLUSION

The determinants associated with individuals living in areas with high STI-related risk scores and low testing rates provide leads for improvement of sexual healthcare access. Opportunities for further exploration include GP education, community-based testing and service (re)allocation.

Mpox outbreak among men who have sex with men in Amsterdam and Rotterdam, the Netherlands: no evidence for undetected transmission prior to May 2022, a retrospective study

Since May 2022, over 21,000 mpox cases have been reported from 29 EU/EEA countries, predominantly among men who have sex with men (MSM). The Netherlands was the fourth most affected country in Europe, with more than 1,200 cases and a crude notification rate of 70.7 per million population. The first national case was reported on 10 May, yet potential prior transmission remains unknown. Insight into prolonged undetected transmission can help to understand the current outbreak dynamics and aid future public health interventions. We performed a retrospective study and phylogenetic analysis to elucidate whether undetected transmission of human mpox virus (hMPXV) occurred before the first reported cases in Amsterdam and Rotterdam. In 401 anorectal and ulcer samples from visitors to centres for sexual health in Amsterdam or Rotterdam dating back to 14 February 2022, we identified two new cases, the earliest from 6 May. This coincides with the first cases reported in the United Kingdom, Spain and Portugal. We found no evidence of widespread hMPXV transmission in Dutch sexual networks of MSM before May 2022. Likely, the mpox outbreak expanded across Europe within a short period in the spring of 2022 through an international highly intertwined network of sexually active MSM.

The timeliness of COVID-19 testing and tracing in eight public health regions in the Netherlands

Background

Testing and Contact Tracing (TCT) was a core strategy in the fight against the spread of SARS-CoV-2. However, little is known about the real-world effectiveness of TCT for COVID-19. Because time is an important conditional factor, we aim to study timeliness of TCT in the Netherlands, and its determinants.

Methods

We used routine COVID-19 TCT registry data from all individuals who tested positive for SARS-CoV-2 at 8 Dutch regional public health services from 1-6-2020 to 28-2-2021 (N = 338,066). We calculated median time intervals of TCT stages. Factors associated with the time between test result and completion of TCT, categorised as ≤ 3 days and &gt;3 days, were assessed using logistic regression adjusting for region, testing site, and laboratory. Potential determinants were: gender, age, country of birth, number of close contacts, working in health-care or education, TCT manpower, and the Oxford Covid-19 Government Response Tracker (OxCGRT).

Results

The median time from symptom onset to TCT completion was 6 days (IQR:3-10). Median times between TCT stages were 1 day (IQR:0-3) for symptom onset to test request, 1 day, (IQR:0-1) for test request to sample collection, 1 day, (IQR:1-1) for sample collection to test result, and 2 days (IQR:1-5) for test result to TCT completion. In 31.7% of tests, time between test result and TCT completion was &gt;3 days. This delay was associated with being older (65+), whereas being younger (0-14), a higher OxCGRT, scaling down TCT, and a higher number of TCT employees were associated with a shorter interval.

Conclusions

Over fifty percent of interval times from symptom onset to TCT completion exceeded the median SARS-CoV-2 incubation period of 5 days. There seems to be little room for improvement on the side of the index case, but there are some implications for logistics such as increasing TCT manpower, and better integration of digital systems.

Key messages

Trends and regional variations of gonococcal antimicrobial resistance in the Netherlands, 2013 to 2019

Background

Gonococcal antimicrobial resistance is emerging worldwide and is monitored in the Netherlands in 18 of 24 Sexual Health Centres (SHC).

Aim

To report trends, predictors and regional variation of gonococcal azithromycin resistance (AZI-R, minimum inhibitory concentration (MIC) > 1 mg/L) and ceftriaxone decreased susceptibility (CEF-DS, MIC > 0.032 mg/L) in 2013–2019.

Methods

SHC reported data on individual characteristics, sexually transmitted infection diagnoses, and susceptibility testing (MIC, measured by Etest). We used multilevel logistic regression analysis to identify AZI-R/CEF-DS predictors, correcting for SHC region. Population differences’ effect on regional variance of AZI-R and CEF-DS was assessed with a separate multilevel model.

Results

The study included 13,172 isolates, predominantly (n = 9,751; 74%) from men who have sex with men (MSM). Between 2013 and 2019, annual proportions of AZI-R isolates appeared to increase from 2.8% (37/1,304) to 9.3% (210/2,264), while those of CEF-DS seemed to decrease from 7.0% (91/1,306) to 2.9% (65/2,276). Among SHC regions, 0.0‒16.9% isolates were AZI-R and 0.0−7.0% CEF-DS; population characteristics could not explain regional variance. Pharyngeal strain origin and consultation year were significantly associated with AZI-R and CEF-DS for MSM, women, and heterosexual men. Among women and heterosexual men ≥ 4 partners was associated with CEF-DS, and ≥ 10 with AZI-R.

Conclusions

No resistance or decreasing susceptibility was found for CEF, the first line gonorrhoea treatment in the Netherlands. Similar to trends worldwide, AZI-R appeared to increase. Regional differences between SHC support nationwide surveillance with regional-level reporting. The increased risk of resistance/decreased susceptibility in pharyngeal strains underlines the importance of including extragenital infections in gonococcal resistance surveillance.

Incident urogenital and anorectal Chlamydia trachomatis in women: the role of sexual exposure and autoinoculation: a multicentre observational study (FemCure)

BACKGROUND

Anorectal infections with Chlamydia trachomatis (CT) are common in women visiting STI outpatient clinics. We here evaluated the risk posed by sexual exposure and by alternate anatomical site infection for incident anorectal and urogenital CT.

METHODS

Prospective multicentre cohort study, FemCure. Participants were treated for CT, and after 4, 6, 8, 10 and 12 weeks, they self-collected anorectal and urogenital samples (swabs) for CT-DNA testing. We calculated the proportion with incident CT, that is, CT incidence (at weeks 6-12) by 2-week time-periods. Compared with no exposure (A), we estimated the risk of incident CT for (B) sexual exposure, (C) alternate site anatomic site infection and (D) both, adjusted for confounders and expressed as adjusted ORs with 95% CIs.

RESULTS

We analysed data of 385 participants contributing 1540 2-week periods. The anorectal CT incidence was 2.9% (39/1343) (95 CI 1.8 to 3.6); 1.3% (A), 1.3% (B), 27.8% (C) and 36.7% (D). The ORs were: 0.91 (95% CI 0.32 to 2.60) (B), 26.0 (95% CI 7.16 to 94.34) (C), 44.26 (95% CI 14.38 to 136.21) (D).The urogenital CT incidence was 3.3% (47/1428) (95% CI 2.4 to 4.4); 0.7% (A), 1.9% (B), 13.9% (C) and 25.4% (D). The ORs were: 2.73 (95% CI 0.87 to 8.61) (B), 21.77 (95% CI 6.70 to 70 71) (C) and 49.66 (95% CI 15.37 to 160.41) (D).

CONCLUSIONS

After initial treatment, an alternate anatomical site CT infection increased the risk for an incident CT in women, especially when also sex was reported. This may suggest a key role for autoinoculation in the re-establishment or persistence of urogenital and anorectal chlamydia infections.

Distance as explanatory factor for sexual health centre utilization: an urban population-based study in the Netherlands

Background

The central sexual health centre (SHC) in the greater Rotterdam area in the Netherlands helps finding people unaware of their STI/HIV status. We aimed to determine a possible association between SHC utilization and travel distance in this urban and infrastructure-rich area. Insight in area-specific utilization helps adjust outreach policies to enhance STI testing.

Methods

The study population consists of all residents aged 15–45 years in the greater Rotterdam area (2015–17). We linked SHC consultation data from STI tested heterosexual clients to the population registry. The association between SHC utilization and distance was investigated by multilevel modelling, adjusting for sociodemographic and area-specific determinants. The data were also stratified by age (aged < 25 years) and migratory background (non-Western), since SHC triage may affect their utilization. We used straight-line distance between postal code area centroid and SHC address as a proxy for travel distance.

Results

We found large area variation in SHC utilization (range: 1.13–48.76 per 1000 residents). Both individual- and area-level determinants determine utilization. Travel distance explained most area variation and was inversely associated with SHC utilization when adjusted for other sociodemographic and area-specific determinants [odds ratio (OR) per kilometre: 0.95; 95% confidence interval (CI): 0.93–0.96]. Similar results were obtained for residents <25 years (OR: 0.95; 95% CI: 0.94–0.96), but not for non-Western residents (OR: 0.99; 95% CI: 0.99–1.00).

Conclusions

Living further away from a central SHC shows a distance decline effect in utilization. We recommend to enhance STI testing by offering STI testing services closer to the population.

Who is providing HIV diagnostic testing? Comparing HIV testing by general practitioners and sexual health centres in five regions in the Netherlands, 2011-2018

OBJECTIVES

General practitioners (GPs) and sexual health centres (SHCs) are the main providers of HIV testing and diagnose two-thirds of HIV infections in the Netherlands. We compared regional HIV testing and positivity by GPs versus SHCs to gain insight into strategies to improve HIV testing, to enable timely detection of HIV infections.

METHODS

Laboratory data (2011-2018) on HIV testing by GPs and SHCs in five Dutch regions with varying levels of urbanisation were evaluated. Regional HIV testing rates per 10 000 residents ≥15 years (mean over period and annual) were compared between providers using negative binomial generalised additive models and additionally stratified by sex and age (15-29 years, 30-44 years, 45-59 years, ≥60 years). χ² tests were used to compare positivity percentage between the two groups of providers.

RESULTS

In the study period, 505 167 HIV tests (GP 36%, SHC 64%) were performed. The highest HIV testing rates were observed in highly urbanised regions, with large regional variations. The HIV testing rates ranged from 28 to 178 per 10 000 residents by GPs and from 30 to 378 per 10 000 by SHCs. Testing rates by GPs were lower than by SHCs in three regions and comparable in two. In all regions, men were tested less by GPs than by SHCs; for women, this varied by region. Among those aged 15-29 years old, GPs' testing rates were lower than SHCs', while this was reversed in older age categories in four out of five regions. The overall mean HIV positivity was 0.4%. In contrast to other regions, positivity in Amsterdam was significantly higher among individuals tested by GPs than by SHCs.

CONCLUSIONS

This retrospective observational study shows that besides SHCs, who perform opt-out testing for key groups, GPs play a prominent role in HIV testing, especially in non-key populations, such as women and older individuals. Large regional variation exists, requiring region-specific interventions to improve GPs' HIV testing practices.

Where to go to in chlamydia control? From infection control towards infectious disease control

OBJECTIVES

The clinical and public health relevance of widespread case finding by testing for asymptomatic chlamydia infections is under debate. We wanted to explore future directions for chlamydia control and generate insights that might guide for evidence-based strategies. In particular, we wanted to know the extent to which we should pursue testing for asymptomatic infections at both genital and extragenital sites.

METHODS

We synthesised findings from published literature and from discussions among national and international chlamydia experts during an invitational workshop. We described changing perceptions in chlamydia control to inform the development of recommendations for future avenues for chlamydia control in the Netherlands.

RESULTS

Despite implementing a range of interventions to control chlamydia, there is no practice-based evidence that population prevalence can be reduced by screening programmes or widespread opportunistic testing. There is limited evidence about the beneficial effect of testing on pelvic inflammatory disease prevention. The risk of tubal factor infertility resulting from chlamydia infection is low and evidence on the preventable fraction remains uncertain. Overdiagnosis and overtreatment with antibiotics for self-limiting and non-viable infections have contributed to antimicrobial resistance in other pathogens and may affect oral, anal and genital microbiota. These changing insights could affect the outcome of previous cost-effectiveness analysis.

CONCLUSION

The balance between benefits and harms of widespread testing to detect asymptomatic chlamydia infections is changing. The opinion of our expert group deviates from the existing paradigm of 'test and treat' and suggests that future strategies should reduce, rather than expand, the role of widespread testing for asymptomatic chlamydia infections.

Educational level and risk of sexually transmitted infections among clients of Dutch sexual health centres

This study aimed to assess whether educational level is an independent determinant for sexually transmitted infections (STIs) among clients consulting Dutch sexual health centres (SHCs). With data from the National STI surveillance database (2015-2017), generalized estimating equations corrected for (sexual) risk factors were used to estimate associations between educational level and chlamydia and gonorrhoea among women (n = 146,020), heterosexual men (n = 82,882) and men who have sex with men (MSM) (n = 52,149) and syphilis and HIV among MSM. Compared to the highest educational level (bachelor/master), all lower educational levels were associated with gonorrhoea among women (adjusted odds ratio 1.40; 95% CI 1.18-1.66 for higher general/pre-university level to 3.57; 95% CI 2.66-4.81 for no education/elementary school level) and heterosexual men (respectively 1.36; 1.06-1.74 to 3.84; 2.89-5.09). Women with no education/elementary school level (1.37; 1.17-1.62) and heterosexual clients with (pre-)vocational secondary educational level were more likely to test positive for chlamydia (women: 1.43; 1.39-1.48 and heterosexual men: 1.31; 1.26-1.37) than clients with higher general/pre-university level or bachelor/master level. In MSM, (pre-)vocational secondary educational level was associated with chlamydia (1.16; 1.11-1.22), gonorrhoea (1.15; 1.10-1.21) and syphilis (1.18; 1.08-1.29), and both (pre-)vocational secondary educational level (1.48; 1.25-1.76) and no education/elementary school level (1.81; 1.09-3.00) were associated with HIV. Lower educational levels were independent determinants of STI in SHC clients. Sexual health centres could facilitate STI testing and care among lower educated people by prioritizing their access.

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.

Confirmatory testing of Neisseria gonorrhoeae in a sexual health clinic: implications for epidemiology and treatment policy

OBJECTIVES

European guidelines advise the use of dual nucleic acid amplification tests (NAAT) in order to minimise the inappropriate diagnosis of Neisseria gonorrhoeae (Ng) in urogenital samples from low prevalence areas and in extragenital specimens. In this cross-sectional study, we investigated the effect of confirmatory testing and confirmation policy on the Ng-positivity in a population visiting the sexual health clinic in Rotterdam, the Netherlands.

METHODS

Apart from urogenital testing, extragenital (oropharyngeal/anorectal) testing was performed for men who have sex with men (MSM) and according to sexual exposure for women and heterosexual men. Ng detection using NAAT was performed using BD Viper and for confirmatory testing BD MAX. Sexual transmitted infection consultation data were merged with diagnostic data from August 2015 through May 2016.

RESULTS

In women (n=4175), oral testing was performed in 84% and 22% were tested anally. In MSM (n=1828), these percentages were 97% and 96%, respectively. Heterosexual men (n=3089) were tested urogenitally. After confirmatory testing, oropharyngeal positivity rates decreased from 7.3% (95% CI 6.5 to 8.2) to 1.5% (95% CI 1.1 to 1.8) in women and from 13.9% (95% CI 12.3 to 15.5) to 5.4% (95% CI 4.3 to 6.4) in MSM. Anorectal positivity rates decreased from 2.6% (95% CI 1.6 to 3.7) to 1.8% (95% CI 0.9 to 2.6) in women and from 9.3% (95% CI 7.9 to 10.7) to 7.2% (95% CI 6.0 to 8.5) in MSM. Urogenital Ng-positivity rate ranged between 3.0% and 4.4% and after confirmation between 2.3% and 3.9%. When confirming oropharyngeal samples, Ng-positivity was 3.8% in women, 3.0% in heterosexual men and 12.5% in MSM. Additional confirmation of urogenital and anorectal samples led to 3.0% Ng positivity in women, 2.7% in heterosexual men and 11.4% in MSM.

CONCLUSIONS

Confirmation of urogenital and anorectal samples reduced the Ng-positivity rates, especially for women. However, as there is no gold standard for the confirmation of Ng infection, the dilemma within public health settings is to choose between two evils: missing diagnoses or overtreatment. In view of the large decrease in oropharyngeal positivity, confirmation Ng-positivity in oropharyngeal samples remains essential to avoid unnecessary treatment.

Determinants associated with viable genital or rectal Chlamydia trachomatis bacterial load (FemCure)

BACKGROUND

Chlamydia trachomatis (CT) is routinely diagnosed by nucleic acid amplification tests (NAATs), which are unable to distinguish between nucleic acids from viable and non-viable CT organisms.

OBJECTIVES

We applied our recently developed sensitive PCR (viability PCR) technique to measure viable bacterial CT load and explore associated determinants in 524 women attending Dutch sexual health centres (STI clinics), and who had genital or rectal CT.

METHODS

We included women participating in the FemCure study (Netherlands, 2016-2017). At the enrolment visit (pre-treatment), 524 were NAAT positive (n=411 had genital and rectal CT, n=88 had genital CT only and n=25 had rectal CT only). We assessed viable rectal and viable genital load using V-PCR. We presented mean load (range 0 (non-viable) to 6.5 log₁₀ CT/mL) and explored potential associations with urogenital symptoms (coital lower abdominal pain, coital blood loss, intermenstrual bleeding, altered vaginal discharge, painful or frequent micturition), rectal symptoms (discharge, pain, blood loss), other anatomical site infection and sociodemographics using multivariable regression analyses.

RESULTS

In genital (n=499) CT NAAT-positive women, the mean viable load was 3.5 log₁₀ CT/mL (SD 1.6). Genital viable load was independently associated with urogenital symptoms-especially altered vaginal discharge (Beta=0.35, p=0.012) and with concurrent rectal CT (aBeta=1.79; p<0.001). Urogenital symptoms were reported by 50.3% of women; their mean genital viable load was 3.6 log₁₀ CT/mL (vs 3.3 in women without symptoms). Of 436 rectal CT NAAT-positive women, the mean rectal viable load was 2.2 log₁₀ CT/mL (SD 2.0); rectal symptoms were reported by 2.5% (n=11) and not associated with rectal viable load.

CONCLUSION

Among women diagnosed with CT in an outpatient clinical setting, viable genital CT load was higher in those reporting urogenital symptoms, but the difference was small. Viable genital load was substantially higher when women also had a concurrent rectal CT.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02694497.

Increasing trends of lymphogranuloma venereum among HIV-negative and asymptomatic men who have sex with men, the Netherlands, 2011 to 2017

Introduction

Lymphogranuloma venereum (LGV), an invasive form of Chlamydia trachomatis infection, has been reported among (mainly HIV-positive) men who have sex with men (MSM) since 2003. In the Netherlands, LGV testing recommendations changed from selective to universal testing in 2015. Changes in tested populations could have led to incomparable LGV positivity rates over time.

Aim

We investigated LGV trends among MSM attending Centres for Sexual Health using surveillance data between 2011 and 2017.

Methods

LGV positivity was calculated among MSM tested for rectal Chlamydia infection and MSM tested specifically for LGV. With multivariable logistic regression analysis, the association between years and LGV was adjusted for testing indicators and determinants.

Results

We included 224,194 consultations. LGV increased from 86 in 2011 to 270 in 2017. Among LGV-positives, proportions of HIV-negative and asymptomatic MSM increased from 17.4% to 45.6% and from 31.4% to 49.3%, respectively, between 2011 and 2017. Among MSM tested for rectal chlamydia, LGV positivity increased from 0.12% to 0.33% among HIV-negatives and remained stable around 2.5% among HIV-positives. Among LGV-tested MSM, LGV positivity increased from 2.1% to 5.7% among HIV-negatives and from 15.1% to 22.1% among HIV-positives. Multivariable models showed increased odds ratios and significant positive associations between years and LGV.

Conclusions

Although increased testing and changes in LGV incidence are difficult to disentangle, we found increasing LGV trends, especially when corrected for confounding. LGV was increasingly attributed to HIV-negative and asymptomatic MSM, among whom testing was previously limited. This stresses the importance of universal testing and continuous surveillance.

Treatment Effectiveness of Azithromycin and Doxycycline in Uncomplicated Rectal and Vaginal Chlamydia trachomatis Infections in Women: A Multicenter Observational Study (FemCure)

Background

Rectal infections with Chlamydia trachomatis (CT) are prevalent in women visiting a sexually transmitted infection outpatient clinic, but it remains unclear what the most effective treatment is. We assessed the effectiveness of doxycycline and azithromycin for the treatment of rectal and vaginal chlamydia in women.

Methods

This study is part of a prospective multicenter cohort study (FemCure). Treatment consisted of doxycycline (100 mg twice daily for 7 days) in rectal CT–positive women, and of azithromycin (1 g single dose) in vaginally positive women who were rectally untested or rectally negative. Participants self-collected rectal and vaginal samples at enrollment (treatment time-point) and during 4 weeks of follow-up. The endpoint was microbiological cure by a negative nucleic acid amplification test at 4 weeks. Differences between cure proportions and 95% confidence intervals (CIs) were calculated.

Results

We analyzed 416 patients, of whom 319 had both rectal and vaginal chlamydia at enrollment, 22 had rectal chlamydia only, and 75 had vaginal chlamydia only. In 341 rectal infections, microbiological cure in azithromycin-treated women was 78.5% (95% CI, 72.6%–83.7%; n = 164/209) and 95.5% (95% CI, 91.0%–98.2%; n = 126/132) in doxycycline-treated women (difference, 17.0% [95% CI, 9.6%–24.7%]; P < .001). In 394 vaginal infections, cure was 93.5% (95% CI, 90.1%–96.1%; n = 246/263) in azithromycin-treated women and 95.4% (95% CI, 90.9%–98.2%; n = 125/131) in doxycycline-treated women (difference, 1.9% [95% CI, –3.6% to 6.7%]; P = .504).

Conclusions

The effectiveness of doxycycline is high and exceeds that of azithromycin for the treatment of rectal CT infections in women.

Clinical Trials Registration

NCT02694497.

Oropharyngeal Chlamydia trachomatis in women; spontaneous clearance and cure after treatment (FemCure)

OBJECTIVES

Women attending STI clinics are not routinely tested for oropharyngeal Chlamydia trachomatis (CT) infections. We aimed to assess spontaneous clearance of oropharyngeal CT and cure after antibiotic treatment in women.

METHODS

Women with vaginal or rectal CT (n=560) were recruited at STI clinics in 2016-2017, as part of the FemCure study (prospective cohort study). We included participants' data from week -1, that is, the diagnosis at initial visit, when clinics applied selective oropharyngeal testing. At week -1, a total of 241 women were oropharyngeally tested (30 positive) and 319 were untested. All FemCure participants provided nurse-collected oropharyngeal samples at study enrolment, that is, week 0, just prior to treatment (n=560), and after treatment at weeks 4 (n=449), 8 (n=433) and 12 (n=427). Samples were tested by nucleic acid amplification test, and at week 0 also by viability testing by viability PCR. Proportions of oropharyngeal CT test results were presented to represent spontaneous clearance and cure.

RESULTS

Of 30 women diagnosed with oropharyngeal CT at week -1, fifteen (50%) were negative at week 0 after a median of 9 days, that is, 'spontaneous clearance'. At week 0, a total of 560 participants were tested, and 46 (8.8%) were oropharyngeal CT positive; 12 of them (26.1%) had viable CT. Of the 46 positive, 36 women had an oropharyngeal test after treatment; 97.2% (35/36) were negative at week 4, that is, 'cure'. Of all women with follow-up visits, the proportion of oropharyngeal CT positive was between 0.5% and 1.6% between weeks 4 and 12. Of those not tested at week -1 (n=319), 8.5% (n=27) were oropharyngeal positive at week 0.

CONCLUSIONS

The clinical importance of oropharyngeal CT in women is debated. We demonstrated that spontaneous clearance of oropharyngeal CT among women is common; of those who did not clear for CT, three-quarters had non-viable CT. After regular treatment with azithromycin or doxycycline, cure rate (97%) of oropharyngeal CT is excellent.

TRIAL REGISTRATION NUMBER

NCT02694497.

Participation, retention, and associated factors of women in a prospective multicenter study on Chlamydia trachomatis infections (FemCure)

Prospective studies are key study designs when attempting to unravel health mechanisms that are widely applicable. Understanding the internal validity of a prospective study is essential to judge a study's quality. Moreover, insights in possible sampling bias and the external validity of a prospective study are useful to judge the applicability of a study's findings. We evaluated participation, retention, and associated factors of women in a multicenter prospective cohort (FemCure) to understand the study's validity.Chlamydia trachomatis (CT) infected adult women, negative for HIV, syphilis, and Neisseria gonorrhoeae were eligible to be preselected and included at three sexually transmitted infection (STI) clinics in the Netherlands (2016-2017). The planned follow-up for participants was 3 months, with two weekly rectal and vaginal CT self-sampling and online questionnaires administered at home and at the clinic. We calculated the proportions of preselected, included, and retained (completed follow-up) women. Associations with non-preselection, noninclusion, and non-retention (called attrition) were assessed (logistic and Cox regression).Among the 4,916 women, 1,763 (35.9%) were preselected, of whom 560 (31.8%) were included. The study population had diverse baseline characteristics: study site, migration background, high education, and no STI history were associated with non-preselection and noninclusion. Retention was 76.3% (n = 427). Attrition was 10.71/100 person/month (95% confidence interval 9.97, 12.69) and was associated with young age and low education. In an outpatient clinical setting, it proved feasible to include and retain women in an intensive prospective cohort. External validity was limited as the study population was not representative (sampling bias), but this did not affect the internal validity. Selective attrition, however (potential selection bias), should be accounted for when interpreting the study results.

Spontaneous clearance of Chlamydia trachomatis accounting for bacterial viability in vaginally or rectally infected women (FemCure)

OBJECTIVES

Spontaneous clearance of Chlamydia trachomatis (CT) infections can occur between diagnosis and treatment. We followed CT patients to assess clearance using a conventional definition (no total CT-DNA, assessed by routine quantitative PCR methods) and a definition accounting for viability, assessed by viability PCR testing.

METHODS

Three outpatient STI clinics included CT-diagnosed women (The Netherlands, 2016-2017, FemCure study); participants had vaginal CT (vCT) and rectal CT (rCT) (group A: n=155), vCT and were rectally untested (group B: n=351), single vCT (group C: n=25) or single rCT (group D: n=29). Follow-up (median interval 9 days) vaginal and rectal samples underwent quantitative PCR testing (detecting total CT-DNA). When PCR positive, samples underwent V-PCR testing to detect 'viable CT' (CT-DNA from intact CT organisms; V-PCR positive). 'Clearance' was the proportion PCR-negative patients and 'clearance of viable CT' was the proportion of patients testing PCR negative or PCR positive but V-PCR negative. We used multivariable logistic regression analyses to assess diagnosis group (A-D), age, days since initial CT test (diagnosis) and study site (STI clinic) in relation to clearance and clearance of viable CT.

RESULTS

Clearance and clearance of viable CT at both anatomic sites were for (A) 0.6% and 3.9%; (B) 5.4% and 9.4%; (C) 32.0% and 52.0% and (D) 27.6% and 41.4%, respectively. In multivariate analyses, women with single infections (groups C and D) had higher likelihood of clearance than women concurrently infected with vCT and rCT (p<0.001).Of rectally untested women (group B), 76.9% had total CT-DNA and 46.7% had viable CT (V-PCR positive) at the rectal site.

CONCLUSIONS

Of untreated female vCT patients who had CT also at the rectal site, or who were rectally untested, only a small proportion cleared CT (in fact many had viable CT) at their follow-up visit (median 9 days). Among single site infected women clearance was much higher.

TRIAL REGISTRATION NUMBER

NCT02694497.

Antibody Testing in Estimating Past Exposure to Chlamydia trachomatis in the Netherlands Chlamydia Cohort Study

The asymptomatic course of Chlamydia trachomatis (CT) infections can result in underestimated CT lifetime prevalence. Antibody testing might improve this estimate. We assessed CT antibody positivity and predictive factors thereof in the Netherlands Chlamydia Cohort Study. Women who had ≥1 CT Nucleic Acid Amplification Test (NAAT) in the study (2008–2011) and who provided self-reported information on NAATs were tested for CT major outer membrane protein specific IgG in serum (2016). CT antibody positivity was assessed and predictive factors were identified using multivariable logistic regressions, separately for CT-positive women (≥1 positive NAAT or ≥1 self-reported positive CT test) and CT-negative women (negative by study NAAT and self-report). Of the 3,613 women studied, 833 (23.1%) were CT -positive. Among the CT-negative women, 208 (7.5%, 95% CI 6.5–8.5) tested positive for CT antibodies. This increased CT lifetime prevalence with 5.8% (95% CI 5.0–6.5). Among women with a CT-positive history, 338 (40.6%, 95% CI 38.5–44.1) tested positive. Predictive factors for antibody positivity related to lower social economic status, sexual risk behavior, multiple infections, higher body mass index, and non-smoking. CT antibody testing significantly increased the lifetime prevalence. Combining NAAT outcomes, self-reported positive tests, and antibody testing reduced misclassification in CT prevalence estimates.

Trends and determinants of antimicrobial susceptibility of Neisseria gonorrhoeae in the Netherlands, 2007 to 2015

Neisseria gonorrhoeae antibiotic resistance surveillance is important to maintain adequate treatment. We analysed 2007–15 data from the Gonococcal Resistance to Antimicrobials Surveillance (GRAS), which currently includes 19 of 25 sexually transmitted infection (STI) centres in the Netherlands. Methods: From each patient with a gonorrhoea culture, the minimum inhibitory concentration (MIC) for several antibiotics was determined. Time trends were assessed by geometric means and linear regression of logarithmic MIC. Determinants for decreased susceptibility to ceftriaxone (MIC > 0.032 mg/L) and resistance to cefotaxime (MIC > 0.125 mg/L) and azithromycin (MIC > 0.5 mg/L) were assessed using stratified logistic regression. Results: 11,768 isolates were analysed. No ceftriaxone resistance was found. In 2015, 27 of 1,425 isolates (1.9%) were resistant to cefotaxime and 176 of 1,623 (10.9%) to azithromycin. Ceftriaxone susceptibility showed no trend (p = 0.96) during the study period, but cefotaxime MIC decreased (p < 0.0001) and azithromycin MIC increased (p < 0.0001) significantly. Concerning ceftriaxone, isolates of men who have sex with men (MSM) from 2013 (p = 0.0005) and 2014 (p = 0.0004) were significantly associated with decreased susceptibility. Significant determinants for cefotaxime resistance were having ≥ 6 partners for women (p = 0.0006). For azithromycin,isolates from MSM collected in 2012 (p = 0.0035), 2013 (p = 0.012), and 2014 (p = 0.013), or from non-Dutch (p < 0.0001) or older (≥ 35 years; p = 0.01) MSM were significantly associated with susceptibility. Resistance in heterosexual men was significantly associated with being ≥ 25 years-old (p = 0.0049) or having 3–5 partners (p = 0.01). Conclusions: No ceftriaxone resistance was found, but azithromycin MIC increased in 2007–15. Resistance determinants could help with focused intervention strategies.

Patient initiated partner treatment for Chlamydia trachomatis infection in the Netherlands: views of patients with and partners notified for Chlamydia

Patient-initiated partner therapy (PIPT) for Chlamydia is not practiced in the Netherlands. We aimed to explore PIPT-willingness in patients infected with Chlamydia and persons notified for Chlamydia (partners) at sexual health clinics (SHCs) and general practitioners’ offices. We performed interviews among 20 heterosexual patients and 21 partners regarding real or hypothetical situations. The interviews were taped, transcribed verbatim and coded using ATLAS.ti7 software for qualitative research. Despite challenges in notifying partners in some cultural groups and some partner types, most patients and partners would cooperate with PIPT. Perceived barriers included unnecessary treatment, risking untreated other sexually transmitted infections and breaking the notification chain. Most patients and partners opted for home-based test-kits before treatment. Partners desired proper packaging of the test and the medication, along with an information insert, a supportive letter from the SHC, information on the internet and the possibility to contact a professional. Although PIPT may support partner notification (PN), many patients and partners prefer a diagnosis before treatment. PIPT with medication or a prescription combined with a home-based test-kit may be the way forward. However, PN seems to be influenced by type of partner and cultural background, requiring differentiated PN and partner therapy methods.

Regional differences in chlamydia and gonorrhoeae positivity rate among heterosexual STI clinic visitors in the Netherlands: contribution of client and regional characteristics as assessed by cross-sectional surveillance data

OBJECTIVES

To assess to what extent triage criteria, client and regional characteristics explain regional differences in Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (Ng) positivity in sexually transmitted infection (STI) clinics.

DESIGN

Retrospective cross-sectional study on the Dutch STI surveillance database of all 24 STI clinics.

PARTICIPANTS

STI clinic visits of heterosexual persons in 2015 with a Ct (n=101 495) and/or Ng test (n=101 081).

PRIMARY OUTCOME MEASURE

Ct and Ng positivity and 95% CI was assessed for each STI clinic. Two-level logistic regression analyses were performed to calculate the percentage change in regional variance (PCV) after adding triage criteria (model 1), other client characteristics (model 2) and regional characteristics (model 3) to the empty model. The contribution of single characteristics was determined after removing them from model 3.

RESULTS

Ct positivity was 14.9% and ranged from 12.6% to 20.0% regionally. Ng positivity was 1.7% and ranged from 0.8% to 3.8% regionally. For Ct, the PCV was 11.7% in model 1, 32.2% in model 2% and 59.3% in model 3. Age, notified for Ct (triage), level of education (other characteristics) and regional degree of urbanisation (region) explained variance most. For Ng, the PCV was 38.7% in model 1, 61.2% in model 2% and 69.1% in model 3. Ethnicity (triage), partner in risk group, level of education and neighbourhood (other characteristics) and regional socioeconomic status (SES) explained variance most. A significant part of regional variance remained unexplained.

CONCLUSIONS

Regional variance was explained by differences in client characteristics, indicating that triage and self-selection influence positivity rates in the surveillance data.Clustering of Ng in low SES regions additionally explained regional variance in Ng; targeted interventions in low SES regions may assist Ng control. Including educational level as triage criterion is recommended. Studies incorporating prevalence data are needed to assess whether regional clustering underlies unexplained regional variance.

Relation between Chlamydia trachomatis infection and pelvic inflammatory disease, ectopic pregnancy and tubal factor infertility in a Dutch cohort of women previously tested for chlamydia in a chlamydia screening trial

OBJECTIVES

A better understanding of Chlamydia trachomatis infection (chlamydia)-related sequelae can provide a framework for effective chlamydia control strategies. The objective of this study was to estimate risks and risk factors of pelvic inflammatory disease (PID), ectopic pregnancy and tubal factor infertility (TFI) with a follow-up time of up until 8 years in women previously tested for chlamydia in the Chlamydia Screening Implementation study (CSI) and participating in the Netherlands Chlamydia Cohort Study (NECCST).

METHODS

Women who participated in the CSI 2008-2011 (n=13 498) were invited in 2015-2016 for NECCST. Chlamydia positive was defined as a positive CSI-PCR test, positive chlamydia serology and/or self-reported infection (time dependent). Data on PID, ectopic pregnancy and TFI were collected by self-completed questionnaires. Incidence rates and HRs were compared between chlamydia-positive and chlamydia-negative women corrected for confounders.

RESULTS

Of 5704 women included, 29.5% (95% CI 28.3 to 30.7) were chlamydia positive. The incidence rate of PID was 1.8 per 1000 person-years (py) (1.6 to 2.2) overall, 4.4 per 1000 py (3.3 to 5.7) among chlamydia positives compared with 1.4 per 1000 py (1.1 to 1.7) for chlamydia negatives. For TFI, this was 0.4 per 1000 py (0.3 to 0.5) overall, 1.3 per 1000 py (0.8 to 2.1) and 0.2 per 1000 py (0.1 to 0.4) among chlamydia positives and negatives, respectively. And for ectopic pregnancy, this was 0.6 per 1000 py (0.5 to 0.8) overall, 0.8 per 1000 py (0.4 to 1.5) and 0.6 per 1000 py (0.4 to 0.8) for chlamydia negatives. Among chlamydia-positive women, the strongest risk factor for PID was symptomatic versus asymptomatic infection (adjusted HR 2.88, 1.4 to 4.5) and for TFI age <20 versus >24 years at first infection (HR 4.35, 1.1 to 16.8).

CONCLUSION

We found a considerably higher risk for PID and TFI in chlamydia-positive women, but the incidence for ectopic pregnancy was comparable between chlamydia-positive and chlamydia-negative women. Overall, the incidence rates of sequelae remained low.

TRIAL REGISTRATION

NTR-5597.

Case series on acute HCV in HIV-negative men in regular clinical practice: a call for action

BACKGROUND

The evidence that HIV treatment as prevention (TasP) and HIV pre-exposure prophylaxis (PrEP) reduces the risk of HIV transmission is overwhelming. But as PrEP and TasP can lead to increased sexual mixing between HIV positive and negative men who have sex with men (MSM), sexually transmitted infections such as acute hepatitis C (HCV), which were thought to be limited to HIV-infected MSM, could become more frequent in HIV uninfected MSM as well. The objective of this study was to describe a series of cases of sexually transmitted HCV infections in HIV-uninfected MSM in the Netherlands and Belgium.

METHODS

Through the Dutch Acute HCV in HIV Study (a Dutch-Belgian prospective multicentre study on the treatment of acute HCV infection, NCT02600325) and the Be-PrEP-ared study (a PrEP project in Antwerp, EudraCT2015-000054-37) several acute HCV infections were detected in HIV-negative men.

RESULTS

A newly acquired HCV infection was diagnosed in ten HIV-negative MSM. HCV was diagnosed at a sexually transmitted infection (STI) clinic (n = 2), by their general practitioner (n = 2), by their HIV physician (n = 1) or at a PrEP clinic (n = 5). Ten patients reported unprotected anal intercourse and four had a concomitant STI at the time of HCV diagnosis. Six patients reported using drugs during sex.

CONCLUSIONS

Our observation calls for a larger nationwide epidemiological study on the prevalence, incidence and risk factors of HCV infection in HIV-uninfected MSM. In the changing landscape of TasP and PrEP, reliable and up-to-date epidemiological data on HCV among HIV-uninfected MSM are needed and will help in developing evidence-based testing policies.

A pill for the partner via the chlamydia patient? Results from a mixed method study among sexual health care providers in the Netherlands

Background

Chlamydia prevalence in the Netherlands remains high despite targeted efforts. Effective Partner Notification (PN) and Partner Treatment (PT) can interrupt transmission and prevent re-infections. Patient Initiated Partner Treatment (PIPT) may strengthen chlamydia control. This study explores the current practice of PN and PT, and benefits of, and barriers and facilitators for PIPT among professionals in sexual health care in the Netherlands.

Methods

A qualitative study was performed among GPs, GP-assistants (GPAs), physicians and nurses working at Sexual Health Clinics (SHC) and key-informants on ethnical diversity using topic lists in focus groups (N = 40) and semi-structured questionnaires in individual interviews (N = 9). Topics included current practices regarding PN and PT, attitude regarding PIPT, and perceived barriers and facilitators for PIPT. Interviews were taped, transcribed verbatim, and coded using ATLAS.ti. A quantitative online questionnaire on the same topics was sent to all physicians and nurses employed at Dutch SHC (complete response rate 26% (84/321)).

Results

The qualitative study showed that all professionals support the need for more attention to PN, and that they saw advantages in PIPT. Mentioned barriers included unwilling PN-behaviour, Dutch legislation, several medical considerations and inadequate skills of GPs. Also, concerns about limited knowledge of cultural sensitivity around PN and PT were raised. Mentioned facilitators of PIPT were reliable home based test-kits, phone-contact between professionals and notified partners, more consultation time for GPs or GPAs and additional training. The online questionnaire showed that SHC employees agreed that partners should be treated as soon as possible, but also that they were reluctant towards PIPT without counselling and testing.

Conclusions

Professionals saw advantages in PIPT, but they also identified barriers hampering the potential introduction of PIPT. Improving PN and counselling skills with specific focus on cultural sensitivity is needed. PIPT could be considered for specific partners. PIPT in combination with home based testing and using e-healthcare should be further explored and developed.

[Chlamydia: a pill for the partner? Results of the PICC-UP project on patient-initiated partner therapy]

OBJECTIVE

Effective partner notification and partner treatment are essential to prevent reinfection with Chlamydia trachomatis. For this reason we investigated the possibilities for patient-initiated partner therapy (PIPT) in the Netherlands.

DESIGN

Database research, questionnaires and interviews.

METHOD

The current practices of partner notification and partner treatment were assessed by means of databases and questionnaires. Facilitators of, and barriers to, the introduction of PIPT were qualitatively explored among professionals at GP practices and sexual health centres. In addition, we interviewed chlamydia patients and their notified partners. Finally, the legal possibilities for PIPT in the Netherlands were explored.

RESULTS

At sexual health centres, regular partners were treated pending test results in 97% of chlamydia cases. Professionals were reluctant to hand out medication to patients for their partners; GPs indicated that they did this in 6% of cases of chlamydia. Patients also saw barriers. The interviewees indicated that the process of partner notification could be improved. Both professionals and patients had a clear preference for combining PIPT with the offer of a (home) test. If those partners notified about chlamydia were not tested, 10% of all gonococcal infections would be missed.

CONCLUSION

Currently, the widespread introduction of PIPT does not seem to be a good option for the Netherlands. PIPT could be implemented for current regular partners and those who would otherwise not be tested. The combination of a home test kit with PIPT is then preferable. Taking current legislation into account, sexual health centres run by local public health departments are probably the best starting position for PIPT. We recommend that this be further explored.

STIs in sex partners notified for chlamydia exposure: implications for expedited partner therapy

OBJECTIVES

Expedited partner therapy (EPT) may reduce chlamydia reinfection rates. However, the disadvantages of EPT for chlamydia include missing the opportunity to test for other STIs and unnecessary use of antibiotics among non-infected partners. As part of a larger study that investigated the feasibility of EPT in the Netherlands, we explored the frequency of STI among a potential EPT target population of chlamydia-notified heterosexual men and women attending STI clinics for testing.

METHODS

Cross-sectional national STI/HIV surveillance data, which contain information on all consultations at STI clinics, were used to calculate STI positivity rates stratified by chlamydia notification and gender, and proportions of STI that were attributable to clients notified for chlamydia.

RESULTS

Of all consultations in 2015 (n=101 710), 14 445 (14.4%) clients reported to be notified exclusively for chlamydia. Among chlamydia-notified clients, the chlamydia positivity rate was 34.2% (n=4947), and consequently 65.8% (n=9488) of them tested negative for chlamydia. Chlamydia-notified clients contributed to 10.2% of all gonorrhoea infections (n=174/1702) and 10.9% of all infectious syphilis, HIV and/or infectious hepatitis B infections (n=15/173).

CONCLUSION

Implementing EPT without additional STI testing for all partners of chlamydia-infected index patients implies that STIs other than chlamydia will be missed. Although the chlamydia positivity rate was high among chlamydia-notified partners, two-thirds would unnecessarily use azithromycin. An evaluation of EPT against the current partner treatment strategy is needed to carefully weigh the potential health gains against the potential health losses and to explore the characteristics of EPT-eligible partners.

Partner notification and partner treatment for chlamydia: attitude and practice of general practitioners in the Netherlands; a landscape analysis

BACKGROUND

Chlamydia prevalence remains high despite scaling-up control efforts. Transmission is not effectively interrupted without partner notification (PN) and (timely) partner treatment (PT). In the Netherlands, the follow-up of partners is not standardized and may depend on GPs' time and priorities. We investigated current practice and attitude of GPs towards PN and PT to determine the potential for Patient-Initiated Partner Treatment, which is legally not supported yet.

METHODS

Multiple data-sources were combined for a landscape analysis. Quantitative data on (potential) PT were obtained from prescriptions in the national pharmacy register (2004-2014) and electronic patient data from NIVEL-Primary Care Database (PCD) and from STI consultations in a subgroup of sentinel practices therein. Furthermore, we collected information on current practice via two short questionnaires at a national GP conference and obtained insight into GPs' attitudes towards PN/PT in a vignette study among GPs partaking in NIVEL-PCD.

RESULTS

Prescription data showed Azithromycin double dosages in 1-2% of cases in the pharmacy register (37.000 per year); probable chlamydia-specific repeated prescriptions or double dosages of other antibiotics in NIVEL-PCD (115/1078) could not be interpreted as PT for chlamydia with certainty. STI consultation data revealed direct PT in 6/100 cases, via partner prescription or double doses. In the questionnaires the large majority of GPs (>95% of 1411) reported to discuss PN of current and ex-partner(s) with chlamydia patients. Direct PT was indicated as most common method by 4% of 271 GPs overall and by 12% for partners registered in the same practice. Usually, GPs leave further steps to the patients (83%), advising patients to tell partners to get tested (56%) or treated (28%). In the vignette study, 16-20% of 268 GPs indicated willingness to provide direct PT, depending on patient/partner profile, more (24-45%) if patients would have the chance to notify their partner first.

CONCLUSION

GPs in the Netherlands already treat some partners of chlamydia cases directly, especially partners registered in the same practice. Follow-up of partner notification and treatment in general practice needs more attention. GPs may be open to implement PIPT more often, provided there are clear guidelines to arrange this legally and practically.

The Netherlands Chlamydia cohort study (NECCST) protocol to assess the risk of late complications following Chlamydia trachomatis infection in women

Background

Chlamydia trachomatis (CT), the most common bacterial sexually transmitted infection (STI) among young women, can result in serious sequelae. Although the course of infection is often asymptomatic, CT may cause pelvic inflammatory disease (PID), leading to severe complications, such as prolonged time to pregnancy, ectopic pregnancy, and tubal factor subfertility. The risk of and risk factors for complications following CT-infection have not been assessed in a long-term prospective cohort study, the preferred design to define infections and complications adequately.

Methods

In the Netherlands Chlamydia Cohort Study (NECCST), a cohort of women of reproductive age with and without a history of CT-infection is followed over a minimum of ten years to investigate (CT-related) reproductive tract complications. This study is a follow-up of the Chlamydia Screening Implementation (CSI) study, executed between 2008 and 2011 in the Netherlands. For NECCST, female CSI participants who consented to be approached for follow-up studies (n = 14,685) are invited, and prospectively followed until 2022. Four data collection moments are foreseen every two consecutive years. Questionnaire data and blood samples for CT-Immunoglobulin G (IgG) measurement are obtained as well as host DNA to determine specific genetic biomarkers related to susceptibility and severity of infection. CT-history will be based on CSI test outcomes, self-reported infections and CT-IgG presence. Information on (time to) pregnancies and the potential long-term complications (i.e. PID, ectopic pregnancy and (tubal factor) subfertility), will be acquired by questionnaires. Reported subfertility will be verified in medical registers. Occurrence of these late complications and prolonged time to pregnancy, as a proxy for reduced fertility due to a previous CT-infection, or other risk factors, will be investigated using longitudinal statistical procedures.

Discussion

In the proposed study, the occurrence of late complications following CT-infection and its risk factors will be assessed. Ultimately, provided reliable risk factors and/or markers can be identified for such late complications. This will contribute to the development of a prognostic tool to estimate the risk of CT-related complications at an early time point, enabling targeted prevention and care towards women at risk for late complications.

Trial registration

Dutch Trial Register NTR-5597. Retrospectively registered 14 February 2016.

Design of the FemCure study: prospective multicentre study on the transmission of genital and extra-genital Chlamydia trachomatis infections in women receiving routine care

Background

In women, anorectal infections with Chlamydia trachomatis (CT) are about as common as genital CT, yet the anorectal site remains largely untested in routine care. Anorectal CT frequently co-occurs with genital CT and may thus often be treated co-incidentally. Nevertheless, post-treatment detection of CT at both anatomic sites has been demonstrated. It is unknown whether anorectal CT may play a role in post-treatment transmission. This study, called FemCure, in women who receive routine treatment (either azithromycin or doxycycline) aims to understand the post-treatment transmission of anorectal CT infections, i.e., from their male sexual partner(s) and from and to the genital region of the same woman. The secondary objective is to evaluate other reasons for CT detection by nucleic acid amplification techniques (NAAT) such as treatment failure, in order to inform guidelines to optimize CT control.

Methods

A multicentre prospective cohort study (FemCure) is set up in which genital and/or anorectal CT positive women (n = 400) will be recruited at three large Dutch STI clinics located in South Limburg, Amsterdam and Rotterdam. The women self-collect anorectal and vaginal swabs before treatment, and at the end of weeks 1, 2, 4, 6, 8, 10, and 12. Samples are tested for presence of CT-DNA (by NAAT), load (by quantitative polymerase chain reaction -PCR), viability (by culture and viability PCR) and CT type (by multilocus sequence typing). Sexual exposure is assessed by online self-administered questionnaires and by testing samples for Y chromosomal DNA. Using logistic regression models, the impact of two key factors (i.e., sexual exposure and alternate anatomic site of infection) on detection of anorectal and genital CT will be assessed.

Discussion

The FemCure study will provide insight in the role of anorectal chlamydia infection in maintaining the CT burden in the context of treatment, and it will provide practical recommendations to reduce avoidable transmission. Implications will improve care strategies that take account of anorectal CT.

Trial registration

ClinicalTrials.gov Identifier: NCT02694497.

Ethnic and regional differences in STI clinic use: a Dutch epidemiological study using aggregated STI clinic data combined with population numbers

OBJECTIVES

Ethnic minorities (EM) from STI-endemic countries are at increased risk to acquire an STI. The objectives of this study were to investigate the difference in STI clinic consultation and positivity rates between ethnic groups, and compare findings between Dutch cities.

METHODS

Aggregated population numbers from 2011 to 2013 of 15-44 year-old citizens of Amsterdam, Rotterdam, The Hague and Utrecht extracted from the population register (N=3 129 941 person-years) were combined with aggregated STI clinic consultation data in these cities from the national STI surveillance database (N=113 536). Using negative binomial regression analyses (adjusted for age and gender), we compared STI consultation and positivity rates between ethnic groups and cities.

RESULTS

Compared with ethnic Dutch (consultation rate: 40.3/1000 person-years), EM from Eastern Europe, Sub-Sahara Africa, Suriname, the Netherlands Antilles/Aruba and Latin America had higher consultation rates (range relative risk (RR): 1.27-2.26), whereas EM from Turkey, North Africa, Asia and Western countries had lower consultation rates (range RR: 0.29-0.82). Of the consultations among ethnic Dutch, 12.2% was STI positive. Positivity rates were higher among all EM groups (range RR: 1.14-1.81). Consultation rates were highest in Amsterdam and lowest in Utrecht independent of ethnic background (range RR Amsterdam vs Utrecht: 4.30-10.30). Positivity rates differed less between cities.

CONCLUSIONS

There were substantial differences in STI clinic use between ethnic groups and cities in the Netherlands. Although higher positivity rates among EM suggest that these high-risk individuals reach STI clinics, it remains unknown whether their reach is optimal. Special attention should be given to EM with comparatively low consultation rates.

Lessons learned from a population-based chlamydia screening pilot

We evaluated process organization and response optimization in a home-based Chlamydia trachomatis (Ct) screening project in the Netherlands among 15- to 29-year-old women and men. The method used was computer-supported data flow, from population sampling to informing participants of the result. A new test kit or a letter reminded non-respondents after six weeks. Fifteen-year olds required parental consent. Urine arrived at the laboratory within 29 days from invitation, and four (1–11) days after collection, indicating good specimen quality. Test kits had a higher response than letters (15 versus 10%). Response in 15-year olds was 33%; with 2% Ct infected sexually active 15 year olds. In Conclusion, purpose made computer software is essential for an efficient screening programme. Sending urine by mail does not impair diagnostics. Reminders are necessary and effective after four weeks. Necessary parental consent for under 16-year olds should not be a deterrent to offer Ct screening to this age group.

Prediction of Chlamydia trachomatis infection to facilitate selective screening on population and individual level: a cross-sectional study of a population-based screening programme

OBJECTIVES

To develop prediction models for Chlamydia trachomatis (Ct) infection with different levels of detail in information, that is, from readily available data in registries and from additional questionnaires.

METHODS

All inhabitants of Rotterdam and Amsterdam aged 16-29 were invited yearly from 2008 until 2011 for home-based testing. Their registry data included gender, age, ethnicity and neighbourhood-level socioeconomic status (SES). Participants were asked to fill in a questionnaire on education, sexually transmitted infection history, symptoms, partner information and sexual behaviour. We developed prediction models for Ct infection using first-time participant data-including registry variables only and with additional questionnaire variables-by multilevel logistic regression analysis to account for clustering within neighbourhoods. We assessed the discriminative ability by the area under the receiver operating characteristic curve (AUC).

RESULTS

Four per cent (3540/80 385) of the participants was infected. The strongest registry predictors for Ct infection were young age (especially for women) and Surinamese, Antillean or sub-Saharan African ethnicity. Neighbourhood-level SES was of minor importance. Strong questionnaire predictors were low to intermediate education level, ethnicity of the partner (non-Dutch) and having sex with casual partners. When using a prediction model including questionnaire risk factors (AUC 0.74, 95% CI 0.736 to 0.752) for selective screening, 48% of the participating population needed to be screened to find 80% (95% CI 78.4% to 81.0%) of Ct infections. The model with registry risk factors only (AUC 0.67, 95% CI 0.656 to 0.675) required 60% to be screened to find 78% (95% CI 76.6% to 79.4%) of Ct infections.

CONCLUSIONS

A registry-based prediction model can facilitate selective Ct screening at population level, with further refinement at the individual level by including questionnaire risk factors.

Partner Notification for Reduction of HIV-1 Transmission and Related Costs among Men Who Have Sex with Men: A Mathematical Modeling Study

Background

Earlier antiretroviral treatment initiation prevents new HIV infections. A key problem in HIV prevention and care is the high number of patients diagnosed late, as these undiagnosed patients can continue forward HIV transmission. We modeled the impact on the Dutch men-who-have-sex-with-men (MSM) HIV epidemic and cost-effectiveness of an existing partner notification process for earlier identification of HIV-infected individuals to reduce HIV transmission.

Methods

Reduction in new infections and cost-effectiveness ratios were obtained for the use of partner notification to identify 5% of all new diagnoses (Scenario 1) and 20% of all new diagnoses (Scenario 2), versus no partner notification. Costs and quality adjusted life years (QALYs) were assigned to each disease state and calculated over 5 year increments for a 20 year period.

Results

Partner notification is predicted to avert 18–69 infections (interquartile range [IQR] 13–24; 51–93) over the course of 5 years countrywide to 221–830 (IQR 140–299; 530–1,127) over 20 years for Scenario 1 and 2 respectively. Partner notification was considered cost-effective in the short term, with increasing cost-effectiveness over time: from €41,476 -€41, 736 (IQR €40,529-€42,147; €40,791-€42,397) to €5,773 -€5,887 (€5,134-€7,196; €5,411-€6,552) per QALY gained over a 5 and 20 year period, respectively. The full monetary benefits of partner notification by preventing new HIV infections become more apparent over time.

Conclusions

Partner notification will not lead to the end of the HIV epidemic, but will prevent new infections and be increasingly cost-effectiveness over time.

Changes in chlamydia control activities in Europe between 2007 and 2012: a cross-national survey

BACKGROUND

In 2012, the levels of chlamydia control activities including primary prevention, effective case management with partner management and surveillance were assessed in 2012 across countries in the European Union and European Economic Area (EU/EEA), on initiative of the European Centre for Disease Control (ECDC) survey, and the findings were compared with those from a similar survey in 2007.

METHODS

Experts in the 30 EU/EEA countries were invited to respond to an online questionnaire; 28 countries responded, of which 25 participated in both the 2007 and 2012 surveys. Analyses focused on 13 indicators of chlamydia prevention and control activities; countries were assigned to one of five categories of chlamydia control.

RESULTS

In 2012, more countries than in 2007 reported availability of national chlamydia case management guidelines (80% vs. 68%), opportunistic chlamydia testing (68% vs. 44%) and consistent use of nucleic acid amplification tests (64% vs. 36%). The number of countries reporting having a national sexually transmitted infection control strategy or a surveillance system for chlamydia did not change notably. In 2012, most countries (18/25, 72%) had implemented primary prevention activities and case management guidelines addressing partner management, compared with 44% (11/25) of countries in 2007.

CONCLUSION

Overall, chlamydia control activities in EU/EEA countries strengthened between 2007 and 2012. Several countries still need to develop essential chlamydia control activities, whereas others may strengthen implementation and monitoring of existing activities.

Sexually transmitted infections among female sex workers tested at STI clinics in the Netherlands, 2006-2013

Background

Specialised sexually transmitted infection (STI) clinics in the Netherlands provide STI care for high-risk groups, including female sex workers (FSW), at the clinic and by outreach visiting commercial sex workplaces with a permit. The objective was to investigate the STI positivity rate and determinants of an STI diagnosis among FSW tested by STI clinics in the Netherlands.

Methods

Sexually transmitted infection clinics report demographic, behavioural and diagnostic information of every consultation to the National Institute for Public Health and the Environment. We analysed all consultations of FSW between 2006 and 2013. Trends in STI positivity rate (chlamydia, gonorrhoea, infectious syphilis, HIV and hepatitis B) were analysed using χ² for trend and logistic regression was used to analyse determinants associated with an STI diagnosis. Differences between consultations at the STI clinic and consultations during outreach were analysed using χ² tests.

Results

The positivity rate for any STI (overall 9.5 %) was stable from 2006 to 2013. Chlamydia positivity rate (overall 7.1 %) decreased (p < 0.001) and gonorrhoea positivity rate (overall 2.6 %) increased (p < 0.001). For gonorrhoea, the highest positivity rate was found oropharyngeal (2.0 %). Characteristics associated with STI were a younger age [adjusted odds ratio (aOR) 0.96, 95 % confidence interval (CI) 0.95–0.97 per year], a previous STI diagnosis (aOR 1.63, 95 % CI 1.38–1.92) and being notified for an STI by partner notification (aOR 2.61, 95 % CI 2.0–3.40). The STI positivity rate was significantly lower among FSW tested at outreach locations (8.6 %) compared to FSW tested at the STI clinic (11.7 %, p < 0.001).

Conclusions

The STI positivity rate among FSW remained stable, but underlying this was a decreasing chlamydia trend and an increasing gonorrhoea trend, suggesting a shift in STI risks among FSW over time. Condom use during oral sex should be promoted since oropharyngeal gonorrhoea was frequently diagnosed and because of the potential spread of antimicrobial resistant gonococci.

Electronic supplementary material

The online version of this article (doi:10.1186/s12982-015-0034-7) contains supplementary material, which is available to authorized users.

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.

Initial evaluation of use of an online partner notification tool for STI, called 'suggest a test': a cross sectional pilot study

OBJECTIVES

Partner notification is crucial for sexually transmitted infection (STI) control. We developed Suggestatest.nl (SAT), an internet-based notification system for verified diagnoses of STI/HIV.

METHODS

SAT uses email, short message service, postal letter or a gay dating site to notify sexual contacts. SAT was piloted at the Public Health STI clinics in two major cities in the Netherlands. We evaluated SAT from March to July 2012 by analysing SAT notifications linked with epidemiological data. Determinants for SAT use were assessed using multivariable logistic regression analysis.

RESULTS

Of 988 index clients receiving a SAT code, overall 139 (14%) notified through SAT, sending 505 notifications (median 2), 84% by text messaging and 15% by email; 88% non-anonymously. Of those intending to use SAT, 23% notified with SAT. Intention to use SAT was the only independent determinant of SAT use in heterosexuals and men who have sex with men. Among the 67 SAT users in Rotterdam, 56% (225/402) of their partners at risk were contactable, and 95% (213/225) of those were notified using SAT. 58% of SAT-notified partners accessed the SAT-website and 20% of them subsequently consulted the STI clinics. STI positivity in partners was lower in those notified by SAT (28% (32/116)) than in those with contact cards (45% (68/152); p<0.001).

CONCLUSIONS

Although the challenges posed by non-contactable partners are not solved by SAT, it is a valuable novel tool for notification of verified STI diagnoses by index patients and providers. In addition to current standard partner notification practice it suits a small number of clients, especially those reporting more than one partner.