Men who have sex with men more often chose daily than event-driven use of pre-exposure prophylaxis: baseline analysis of a demonstration study in Amsterdam.

The Amsterdam PrEP project is a prospective, open-label demonstration study at a large sexually transmitted infection (STI) clinic. We examined the uptake of PrEP; the baseline characteristics of men who have sex with men (MSM) and transgender persons initiating PrEP; their choices of daily versus event-driven PrEP and the determinants of these choices

Men who have sex with men more often chose daily than event-driven use of pre-exposure prophylaxis: baseline analysis of a demonstration study in Amsterdam.

The Amsterdam PrEP project is a prospective, open-label demonstration study at a large sexually transmitted infection (STI) clinic. We examined the uptake of PrEP; the baseline characteristics of men who have sex with men (MSM) and transgender persons initiating PrEP; their choices of daily versus event-driven PrEP and the determinants of these choices

Molecular Assessment of Bacterial Vaginosis by Lactobacillus Abundance and Species Diversity

Background To date, women are most often diagnosed with bacterial vaginosis (BV) using microscopy based Nugent scoring or Amsel criteria. However, the accuracy is less than optimal. The aim of the present study was to confirm the identity of known BV-associated composition profiles and evaluate indicators for BV using three molecular methods. Methods Evaluation of indicators for BV was carried out by 16S rRNA amplicon sequencing of the V5-V7 region, a tailor-made 16S rRNA oligonucleotide-based microarray, and a PCR-based profiling technique termed IS-profiling, which is based on fragment variability of the 16S-23S rRNA intergenic spacer region. An inventory of vaginal bacterial species was obtained from 40 females attending a Dutch sexually transmitted infection outpatient clinic, of which 20 diagnosed with BV (Nugent score 7–10), and 20 BV negative (Nugent score 0–3). Results Analysis of the bacterial communities by 16S rRNA amplicon sequencing revealed two clusters in the BV negative women, dominated by either Lactobacillus iners or Lactobacillus crispatus and three distinct clusters in the BV positive women. In the former, there was a virtually complete, negative correlation between L. crispatus and L. iners. BV positive subjects showed cluster profiles that were relatively high in bacterial species diversity and dominated by anaerobic species, including Gardnerella vaginalis, and those belonging to the Families of Lachnospiraceae and Leptotrichiaceae. Accordingly, the Gini-Simpson index of species diversity, and the relative abundance Lactobacillus species appeared consistent indicators for BV. Under the conditions used, only the 16S rRNA amplicon sequencing method was suitable to assess species diversity, while all three molecular composition profiling methods were able to indicate Lactobacillus abundance in the vaginal microbiota. Conclusion An affordable and simple molecular test showing a depletion of the genus Lactobacillus in combination with an increased species diversity of vaginal microbiota could serve as an alternative and practical diagnostic method for the assessment of BV

Molecular assessment of bacterial vaginosis by Lactobacillus abundance and species diversity

__Background:__ To date, women are most often diagnosed with bacterial vaginosis (BV) using microscopy based Nugent scoring or Amsel criteria. However, the accuracy is less than optimal. The aim of the present study was to confirm the identity of known BV-associated composition profiles and evaluate indicators for BV using three molecular methods. __Methods:__ Evaluation of indicators for BV was carried out by 16S rRNA amplicon sequencing of the V5-V7 region, a tailor-made 16S rRNA oligonucleotide-based microarray, and a PCR-based profiling technique termed IS-profiling, which is based on fragment variability of the 16S-23S rRNA intergenic spacer region. An inventory of vaginal bacterial species was obtained from 40 females attending a Dutch sexually transmitted infection outpatient clinic, of which 20 diagnosed with BV (Nugent score 7-10), and 20 BV negative (Nugent score 0-3). __Results:__ Analysis of the bacterial communities by 16S rRNA amplicon sequencing revealed two clusters in the BV negative women, dominated by either Lactobacillus iners or Lactobacillus crispatus and three distinct clusters in the BV positive women. In the former, there was a virtually complete, negative correlation between L. crispatus and L. iners. BV positive subjects showed cluster profiles that were relatively high in bacterial species diversity and dominated by anaerobic species, including Gardnerella vaginalis, an

International epidemiological studies on HIV, HCV and STI

This thesis comprises international epidemiological studies on HIV, Hepatitis C (HCV) and sexually transmitted infections (STI) and the evaluation of STI diagnostic tests with the ultimate goal to decrease spread and disease burden of these infections. The main conclusions are: 1. Without the use of HIV-therapy, long term progression-free survival of HIV is a rare but real phenomenon. 2. HCV incidence had already increased among HIV positive men who have sex with men (MSM) in the period before 2000 but from 2002 onwards it increased substantially. 3. In the era of combination antiretroviral therapy availability, HIV/HCV co-infected individuals have higher risk of death from hepatitis/liver disease and also a higher HIV/AIDS-related mortality is higher than those with only HIV infection. 4. In Suriname, chlamydia is more frequent among youngsters and among individuals of Creole and Javanese ethnicity. Sexual mixing with partners of another ethnicity was not associated with chlamydia. 5. Surinamese migrants in the Netherlands are not an effective bridge population for chlamydia transmission between Suriname and the Netherlands. 6. The chlamydia epidemic in MSM is an isolated phenomenon, distinct from the heterosexual network. 7. Although claimed differently by the manufacturer, the chlamydia rapid test performs far below expectations. Especially low chlamydia load infections are missed. 8. The performance of a self-collected rectal swab for diagnosis of chlamydia and gonorrhoea is comparable to a provider-collected rectal swab. 9. The syphilis real-time PCR is a fast, efficient and reliable test to diagnose primary syphilis, both in an STI patient clinic and a general practitioner setting

HIV and hepatitis C treatment uptake among people who use drugs participating in the Amsterdam Cohort Studies, 1985-2015

Background: HIV-positive people who use drugs (PWUD) start antiretroviral therapy (ART) later than other risk groups, and among HCV-positive PWUD, HCV treatment uptake is low. Nowadays, HCV direct acting antivirals (DAAs) are available and reimbursed in the Netherlands (since 2014). The Amsterdam Cohort Studies (ACS), initiated in 1985, provides us the opportunity to describe temporal trends in ART and HCV-treatment uptake among PWUD through 2015. Methods: We analyzed data from PWUD participating in the ACS between 1985 and 2015. ART and HCV-treatment data were obtained from ACS questionnaires and medical records. Treatment uptake was defined by: treatment initiation (the proportion initiating any kind of ART/HCV treatment when treatment-naive) and coverage (the proportion ever treated for HIV/HCV) among all HIV-/HCV-RNA-positive PWUD. Each was calculated per calendar year. We estimated the cumulative probability of ART uptake in the pre-cART ( <1996) and cART era (January 1,1996) among HIV seroconverters, with all-cause mortality as a competing risk. Results: Of 1305 PWUD, 263 (20.2%) were HIV-antibody positive and 810 (62.1%) were HCV-antibody positive, at study entry. ART coverage increased over time, from 5.7% in 1990 and 42.2% in 1996 to 91.7% in 2015. The proportion initiating ART ranged from 4.8% in 1990 to 33.3% in 2011. At 8 years after HIV seroconversion, cumulative probability of ART uptake was 42.5% in the pre-cART era and 61.5% in the cART era. HCV treatment initiation peaked in 2006 (9.7%). HCV-treatment coverage was 43.9% in 2015 but lower among HIV-coinfected (23.5%) than HCV-monoinfected PWUD (52.5%). In 2015, 3.0% initiated HCV treatment with DAAs. Conclusion: We observed an increase in ART and HCV-treatment coverage among PWUD over time. As expected, ART uptake was higher in the CART era than the pre-cART era. Although in 2015 HCV treatment coverage was relatively high, DAA uptake was still low. (C) 2017 Elsevier B.V. All rights reserve

Determinants of persistent spread of HIV in HCV-infected populations of injecting drug users

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are both transmitted through populations of injecting drug users (IDU) by the sharing of contaminated syringes. Prevalence of HCV is high in most IDU populations, whereas HIV prevalence varies considerably across populations. Understanding the dynamics of these interacting infections may allow us to use HCV prevalence as an indicator for the risk of persistent spread of HIV. We developed a mathematical model that describes the spread of both HCV and HIV in an IOU population. The model allows for HCV-HIV co-infection and increased disease related mortality for both infections. Using this model we investigated how HIV and HCV prevalence both depend on level and heterogeneity of injecting risk behaviour, and how HIV and HCV prevalence are related. To gain knowledge of actual risk behaviour we analysed data from the Amsterdam Cohort Study (ACS) of drug users. We find that there is a threshold HCV prevalence at which HIV can invade into an IDU population; below threshold HIV cannot spread. This threshold depends strongly on heterogeneity of risk behaviour in the population, as well as on whether sharing is more likely to occur within or between risk behaviour groups. We find that our model agrees with the observed relationship between HCV and HIV prevalence as described by Vickerman et al. (2010), when in addition to risk heterogeneity as fitted from the ACS, we also assume that most contacts (>90%) occur amongst IOU of the same risk level (assortative mixing). We conclude that HCV prevalence can be used as an indicator of risk for successful HIV introduction into an IDU population. However, information on risk heterogeneity is required for determining this risk, and also for designing effective prevention strategies. (C) 2012 Elsevier B.V. All rights reserve

The cervicovaginal microbiota in women notified for chlamydia trachomatis infection: A case-control study at the sexually transmitted infection outpatient clinic in Amsterdam, The Netherlands

Background. Increasing evidence suggests that the cervicovaginal microbiota (CVM) plays an important role in acquiring sexually transmitted infections (STIs). Here we study the CVM in a population of women notified by a sex partner for Chlamydia trachomatis infection. Methods. We included 98 women who were contact-traced by C. trachomatis-positive sex partners at the STI outpatient clinic in Amsterdam, the Netherlands, and analyzed their cervicovaginal samples and clinical data. CVMs were characterized by sequencing the V3/V4 region of the 16S ribosomal RNA gene and by hierarchical clustering. Characteristics associating with C. trachomatis infection were examined using bivariable and multivariable logistic regression analysis. Results. The CVM was characterized for 93 women, of whom 52 tested C. trachomatis positive and 41 C. trachomatis negative. We identified 3 major CVM clusters. Clustered CVM predominantly comprised either diverse anaerobic bacteria (n = 39 [42%]), Lactobacillus iners (n = 32 [34%]), or Lactobacillus crispatus (n = 22 [24%]). In multivariable analysis, we found that CVM was significantly associated with C. trachomatis infection (odds ratio [OR], 4.2 [95% confidence interval {CI}, 1.2-15.4] for women with diverse anaerobic CVM and OR, 4.4 [95% CI, 1.3-15.6], for women with L. iners-dominated CVM, compared with women with L. crispatus-dominated CVM), as was younger age (OR, 3.1 [95% CI, 1.1-8.7] for those ≤21 years old) and reporting a steady sex partner (OR, 3.6 [95% CI, 1.4-9.4]). Conclusions. Women who tested positive for Chlamydia trachomatis infection after having been contact-traced by a chlamydiapositive partner were more likely to have CVM dominated by L. iners or by diverse anaerobic bacteria, than by L. crispatus

Design of a syndemic based intervention to facilitate care for men who have sex with men with high risk behaviour: the syn.bas.in randomized controlled trial

Men who have sex with men (MSM) constitute a risk group for sexual transmitted infections (STIs), including HIV. Despite counselling interventions, risk behaviour remains high. Syndemic theory holds that psychosocial problems often co-occur, interact and mutually reinforce each other, thereby increasing high risk behaviours and co-occurring diseases. Therefore, if co-occurring psychosocial problems were assessed and treated simultaneously, this might decrease high risk behaviour and disease. An open label randomized controlled trial will be conducted among 150 MSM with high risk behaviour recruited from the STI clinic of Amsterdam. Inclusion criteria are: HIV negative MSM with two STI and/or PEP treatment in the last 24 months, or HIV positive MSM with one STI in the last 24 months. All participants get questionnaires on the following syndemic domains: ADHD, depression, anxiety disorder, alexithymia and sex- and drug addiction. Participants in the control group receive standard care: STI screenings every three months and motivational interviewing based counselling. Participants in the experimental group receive standard care plus feedback based on the results of the questionnaires. All participants can be referred to co-located mental health or addiction services. The primary outcome is help seeking behaviour for mental health problems and/or drug use problems. The secondary outcomes are STI incidence and changes in sexual risk behaviour (i.e. condom use, number of anal sex partners, drug use during sex). This study will provide information on syndemic domains among MSM who show high risk behaviour and on the effect of screening and referral on help seeking behaviour and health (behaviour) outcomes. Trial Registration at clinicaltrail.gov, identifier NCT0285993

Trends in antimicrobial susceptibility for azithromycin and ceftriaxone in Neisseria gonorrhoeae isolates in Amsterdam, the Netherlands, between 2012 and 2015

Resistance of Neisseria gonorrhoeae to azithromycin and ceftriaxone has been increasing in the past years. This is of concern since the combination of these antimicrobials is recommended as the first-line treatment option in most guidelines. To analyse trends in antimicrobial resistance, we retrospectively selected all consultations with a positive N. gonorrhoeae culture at the sexually transmitted infection clinic, Amsterdam, the Netherlands, from January 2012 through September 2015. Minimum inhibitory concentrations (MICs) for azithromycin and ceftriaxone were analysed per year, and determinants associated with decreased susceptibility to azithromycin (MIC > 0.25 mg/L) or ceftriaxone (MIC > 0.032 mg/L) were assessed. Between 2012 and 2015 azithromycin resistance (MIC > 0.5 mg/L) was around 1.2%, the percentage of isolates with intermediate MICs (> 0.25 and ≤ 0.5 mg/L) increased from 3.7% in 2012, to 8.6% in 2015. Determinants associated with decreased azithromycin susceptibility were, for men who have sex with men (MSM), infections diagnosed in the year 2014, two infected sites, and HIV status (HIV; associated with less decreased susceptibility); for heterosexuals this was having ≥ 10 sex partners (in previous six months). Although no ceftriaxone resistance (MIC > 0.125 mg/L) was observed during the study period, the proportion of isolates with decreased ceftriaxone susceptibility increased from 3.6% in 2012, to 8.4% in 2015. Determinants associated with decreased ceftriaxone susceptibility were, for MSM, infections diagnosed in 2014, and pharyngeal infections; and for heterosexuals, infections diagnosed in 2014 or 2015, being of female sex, and having ≥ 10 sex partners. Continued decrease of azithromycin and ceftriaxone susceptibility will threaten future treatment of gonorrhoea. Therefore, new treatment strategies are warrante