Sexually transmissible infections among female sex workers in Amsterdam between 2011 and 2016: does risk vary by work location?

Background Female sex workers (FSW) are at risk for sexually transmissible infections (STI). This study aimed to investigate whether the risk for chlamydia and gonorrhoea differs by work location among FSW in Amsterdam. Additionally, trends in STI positivity rates between 2011 and 2016 were assessed. METHODS: This was a retrospective analysis of routinely collected clinical data during STI consultations of FSW by the Prostitution and Healthcare Centre (P&G292). Work location was categorised as window prostitution, escorts/homeworkers, clubs/brothels/private houses/massage salons and other. RESULTS: In total, 7558 STI consultations of 2529 FSW in the period 2011-16 were included. Positivity rates for chlamydia and gonorrhoea were 6.6% and 2.0%, respectively. Infectious hepatitis B virus, syphilis and HIV were diagnosed in <0.2% of consultations. Positivity rates of chlamydia and rectal gonorrhoea differed significantly by work location (P < 0.001). Genital and rectal chlamydia and rectal gonorrhoea were significantly less likely among women working in window prostitution, except for the other-group. Risk factors for STI did not vary by work location. Among women working in window prostitution, positivity rates for oropharyngeal and genital chlamydia and genital gonorrhoea were significantly decreasing between 2011 and 2016 (P trend <0.05). CONCLUSIONS: The higher STI positivity among escorts/homeworkers and FSW in clubs/brothels/private houses/massage salons emphasises the need for extra attention to improve condom use and STI testing in this group. Factors associated with STI did not vary by work location, thus interventions, including those used by P&G292, to reduce STI risk, can be used for women at all work locations.

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.

Frequency and determinants of consistent STI/HIV testing among men who have sex with men testing at STI outpatient clinics in the Netherlands: a longitudinal study.

OBJECTIVES: Men who have sex with men (MSM) are at highest risk for STIs and HIV infections in the Netherlands. However, official guidelines on STI testing among MSM are lacking. They are advised to test for STIs at least every six months, but their testing behaviour is not well known. This study aimed to get insight into the proportion and determinants of consistent 6-monthly STI testing among MSM testing at STI outpatient clinics in the Netherlands. METHODS: This study included longitudinal surveillance data of STI consultations among MSM from all 26 STI outpatient clinics in the Netherlands between 1 June 2014 and 31 December 2015. Multinomial logistic regression analysis was used to identify determinants of consistent 6-monthly testing compared with single testing and inconsistent testing. Determinants of time between consultations among men with multiple consultations were analysed using a Cox Prentice-Williams-Peterson gap-time model. RESULTS: A total of 34 605 STI consultations of 18 634 MSM were included. 8966 (48.1%) men had more than one consultation, and 3516 (18.9%) men tested consistently 6-monthly. Indicators of high sexual risk behaviour, including having a history of STI, being HIV positive and having more than 10 sex partners, were positively associated with both being a consistent tester and returning to the STI clinic sooner. Men who were notified by a partner or who reported STI symptoms were also more likely to return to the STI clinic sooner, but were less likely to be consistent testers, identifying a group of event-driven testers. CONCLUSIONS: The proportion of consistent 6-monthly testers among MSM visiting Dutch STI outpatient clinics was low. Testing behaviour was associated with sexual risk behaviour, but exact motives to test consistently remain unclear. Evidence-based testing guidelines are needed to achieve optimal reductions in STI transmission in the future.

Determinants of Human Papillomavirus Vaccination Intention Among Female Sex Workers in Amsterdam, the Netherlands.

INTRODUCTION: Female sex workers (FSWs) are at risk for human papillomavirus (HPV)-induced diseases but are currently not targeted by the HPV vaccination program in the Netherlands. We explored determinants of their intention to get vaccinated against HPV in case vaccination would be offered to them. METHODS: In 2016, FSWs 18 years and older having a sexually transmitted infection consultation with the Prostitution & Health Center (P&G292) in Amsterdam, either at the clinic or at their working location, were invited to complete a questionnaire assessing sociopsychological determinants of HPV vaccination intention (scale ranging from -3 to +3). Determinants of HPV vaccination intention were assessed with univariable and multivariable linear regression. In addition, we explored the effect of out-of-pocket payment on intention. RESULTS: Between May and September 2016, 294 FSWs participated. The median age was 29 years (interquartile range, 25-37 years). Human papillomavirus vaccination intention was high (mean, 2.0; 95% confidence interval [CI], 1.8-2.2). In multivariable analysis, attitude (ß = 0.6; 95% CI, 0.5-0.7), descriptive norm (ß = 0.2; 95% CI, 0.1-0.3), self-efficacy (ß = 0.2; 95% CI, 0.1-0.3), beliefs (ß = 0.1; 95% CI, 0.0-0.2), and subjective norm (ß = 0.1; 95% CI, 0.0-0.2) seemed to be the strongest predictors of HPV vaccination intention (R = 0.54). Human papillomavirus vaccination intention decreased significantly to a mean of 0.2 when vaccination would require out-of-pocket payment of &OV0556;350. CONCLUSIONS: The HPV vaccination intention among FSWs seems relatively high and is most strongly constituted in attitudinal, normative, and self-efficacy beliefs. Out-of-pocket payment will probably have a negative impact on their HPV vaccination acceptability.

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 .

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.