Sexual risk and STI testing behaviour among Dutch female and male self-employed sex workers; a cross-sectional study using an Internet based survey.

BACKGROUND: Sex workers are men, women or transgender people who have sex in exchange for money or goods. Self-employed sex workers solicit clients independently from a third-party. Self-employed sex workers are at risk of acquiring sexually transmitted infections (STIs) through their work. We performed a cross-sectional study, using an Internet survey conducted in 2019-2020 aiming to establish sexual risk behaviour and STI testing behaviour among female and male self-employed sex workers. RESULTS: A total of 76 female self-employed sex workers (FSW) and 79 male self-employed sex workers (MSW) completed the survey. Both FSW and MSW more often had sex with partners of the opposite sex during work (65.8% FSW, 61.6% MSW) and in their private life (63.3% FSW; 64.5% MSW). During vaginal sex 35.7% of FSW and 29.6% of MSW did not always use a condom. Inconsistent condom use was observed in 35.7% of FSW and 29.6% of MSW during vaginal sex, 46.2% of FSW and 35.7% of MSW did not always use a condom during receptive anal sex. The majority of both FSW and MSW tested for STIs in the past year (67.1% FSW; 67.7% MSW) and 67.5% were aware of the possibility of low-threshold testing at an STI clinic. In the past year, 11.6% of FSW and 8.1% of MSW had an STI. CONCLUSION: The reported STI positivity rate among self-employed sex workers was not very high. However, STI prevention efforts remain important considering the low compliance with condom use during sex work. Moreover, not testing for STIs in the past year was substantial with one-third of both FSW and MSW and one-third of both FSW and MSW being unaware of the possibility of low-threshold testing at an STI clinic, warranting efforts to increase testing uptake in this population.

Young male sex workers are at high risk for sexually transmitted infections, a cross-sectional study from Dutch STI clinics, the Netherlands, 2006-2012.

BACKGROUND: Male sex workers (MSW) are particularly exposed to sexually transmitted infections (STI) including HIV. In the Netherlands, data about STI among MSW are scarce. We estimated chlamydia, gonorrhoea, syphilis and HIV diagnoses among MSW attending STI clinics and determined associated factors to guide prevention policies. METHODS: Using 2006-2012 cross-sectional national surveillance data from Dutch STI clinics, we calculated the proportion of consultations with a positive test for any of three bacterial STI or HIV among MSW. Associated factors were determined by using Poisson logistic regression with robust variance. RESULTS: We identified 3,053 consultations involving MSW, of which 18.1 % included at least one positive bacterial STI test and 2.5 % a positive HIV test. Factors associated with bacterial STI and/or HIV diagnoses were respectively age groups < 35 y.o. and self-reporting homo- or bisexual preferences (aRR = 1.6; 95 % CI: 1.3-2.1), and age group 25-34 y.o. (aRR = 2.7; 95 % CI: 1.2-6.5) and self-reporting homo- or bisexual preferences (aRR = 24.4; 95 % CI: 3.4-176.9). Newly diagnosed and pre-existing HIV infection were associated with an increased risk for bacterial STI (aRR = 2.7, 95 % CI: 1.7-2.6 and aRR = 2.1, 95 % CI: 2.2-3.4 respectively). MSW with no history of HIV screening were more likely to be tested positive for HIV compared to those with a previous HIV-negative test (aRR = 2.6, 95 % CI: 1.6-4.3). CONCLUSION: Health promotion activities should target MSW who are young, homo- or bisexual, those who are HIV-infected or who have never been tested for HIV, to increase early diagnosis, prevention and treatment.

Public health measures to control the spread of antimicrobial resistance in Neisseria gonorrhoeae in men who have sex with men.

Gonorrhoea is one of the most common sexually transmitted infections. The control of gonorrhoea is extremely challenging because of the repeated development of resistance to the antibiotics used for its treatment. We explored different strategies to control the spread of antimicrobial resistance and prevent increases in gonorrhoea prevalence. We used a mathematical model that describes gonorrhoea transmission among men who have sex with men and distinguishes gonorrhoea strains sensitive or resistant to three antibiotics. We investigated the impact of combination therapy, switching first-line antibiotics according to resistance thresholds, and other control efforts (reduced sexual risk behaviour, increased treatment rate). Combination therapy can delay the spread of resistance better than using the 5% resistance threshold. Increased treatment rates, expected to enhance gonorrhoea control, may reduce gonorrhoea prevalence only in the short term, but could lead to more resistance and higher prevalence in the long term. Re-treatment of resistant cases with alternative antibiotics can substantially delay the spread of resistance. In conclusion, combination therapy and re-treatment of resistant cases with alternative antibiotics could be the most effective strategies to prevent increases in gonorrhoea prevalence due to antimicrobial resistance.

Sexual behaviour and sexually transmitted infections in sexually transmitted infection clinic attendees in the Netherlands, 2007-2011.

High annual figures of sexually transmitted infections (STIs) are diagnosed in the Netherlands despite significant efforts to control them. Herein, we analyse trends and determinants of STI diagnoses, co-infections, and sexual risks among visitors of 26 STI clinics between 2007 and 2011. We recorded increased positivity rates of STIs (chlamydia, syphilis, gonorrhoea, and/or HIV) in women and heterosexual men up to 12.6% and 13.4%, respectively, in 2011, while rates in men having sex with men (MSM) were stable but high (18.8%) through the documented years. Younger age, origin from Surinam/Antilles, history of previous STI, multiple partners, or a previous notification are the identified risk factors for an STI in this population. Known HIV-infected men (MSM and heterosexuals) were at highest risk for co-infections (relative rate heterosexual men: 15.6; MSM: 11.6). STI positivity rates remained high (MSM) or increased over time (women and heterosexual men), a fact that highlights the importance of continuing STI prevention. Most importantly, the very high STI co-infection rates among HIV-positive men requires intensified STI reduction strategies to put an end to the vicious circle of re-infection and spread of HIV and other STIs.

The value of testing multiple anatomic sites for gonorrhoea and chlamydia in sexually transmitted infection centres in the Netherlands, 2006-2010.

National surveillance data from 2006 to 2010 of the Dutch sexually transmitted infection (STI) centres were used to analyse current practices on testing extragenital sites for chlamydia and gonorrhoea in men who have sex with men (MSM) and women. In MSM, 76.0% and 88.9% were tested at least at one extragenital site (pharyngeal and/or anorectal) for chlamydia and gonorrhoea, respectively; for women this was 20.5% and 30.2%. Testing more than one anatomic site differed by STI centre, ranging from 2% to 100%. In MSM tested at multiple sites, 63.0% and 66.5% of chlamydia and gonorrhoea diagnoses, respectively, would have been missed if screened at the urogenital site only, mainly anorectal infections. For women tested at multiple sites, the proportions of missed chlamydia and gonorrhoea diagnoses would have been 12.9% and 30.0%, respectively. Testing extragenital sites appears warranted, due to the numerous infections that would have been missed. Adding anorectal screening to urogenital screening for all MSM visiting an STI centre should be recommended. Since actual testing practices differ by centre, there is a need for clearer guidelines. Routine gonorrhoea and chlamydia screening at multiple sites in STI centres should be investigated further as this might be a more effective approach to reduce transmission than current practice.

Comparing two definitions of ethnicity for identifying young persons at risk for chlamydia.

Ethnic disparities in chlamydia infections in The Netherlands were assessed, in order to compare two definitions of ethnicity: ethnicity based on country of birth and self-defined ethnicity. Chlamydia positivity in persons aged 16-29 years was investigated using data from the first round of the Chlamydia Screening Implementation (CSI, 2008-2009) and surveillance data from STI centres (2009). Logistic regression modelling showed that being an immigrant was associated with chlamydia positivity in both CSI [adjusted odds ratio (aOR) 2·3, 95% confidence interval (CI) 2·0-2·6] and STI centres (aOR 1·4, 95% CI 1·3-1·5). In both settings, 60% of immigrants defined themselves as Dutch. Despite the difference, classification by self-defined ethnicity resulted in similar associations between (non-Dutch) ethnicity and chlamydia positivity. However, ethnicity based on country of birth explained variation in chlamydia positivity better, and is objective and constant over time and therefore more useful for identifying young persons at higher risk for chlamydia infection.

Increasing trend in gonococcal resistance to ciprofloxacin in The Netherlands, 2006-8.

INTRODUCTION: Rapid development of Neisseria gonorrhoeae resistance to several antibiotics in recent years threatens treatment and prevention. Targeted surveillance of new resistance patterns and insight into networks and determinants are essential to control this trend. METHODS: Since the Gonococcal Resistance to Antimicrobials Surveillance (GRAS) project was implemented within the Dutch national sexually transmitted infection (STI) surveillance network in July 2006, participating STI centres have collected a culture from each gonorrhoea patient. Isolates were tested for susceptibility to penicillin, tetracycline, ciprofloxacin and cefotaxime using Etest. Logistic regression was used to determine risk factors for ciprofloxacin resistance. RESULTS: Between July 2006 and July 2008, prevalence of resistance to penicillin was 10%, to tetracycline 22% and to ciprofloxacin 42%. Resistance to cefotaxime was not found, although minimum inhibitory concentrations higher than 0.125 mg/l drifted upward (p<0.05). Ciprofloxacin resistance rose from 35% in 2006 to 46% in 2008 (p<0.05), despite 2003 guidelines naming cefotaxime as first-choice therapy. In men, ciprofloxacin resistance was higher in men having sex with men (MSM) than in heterosexual men (adjusted OR 2.0, 95% CI : 1.5 to 2.6). In women, it was higher in commercial sex workers (adjusted OR 25.0, 95% CI 7.7 to 78.2) and women aged over 35 years (adjusted OR 8.2, 95% CI 3.0 to 22.7) than in other women. CONCLUSION: Ciprofloxacin resistance in The Netherlands is increasing, and is particularly found in MSM, older women, and female sex workers. No resistance to current first-choice therapy was found, but alertness to potential clinical failures is essential. By merging epidemiological and microbiological data in GRAS, specific high-risk transmission groups can be identified and policy adjusted when needed.

Hepatitis B vaccination targeted at behavioural risk groups in the Netherlands: does it work?

In November 2002, the Netherlands adopted a vaccination program targeted at behavioural risk groups. Between January 2003 and December 2007, 1386 patients acutely infected with HBV were reported. Reported cases declined from 326 in 2003 to 220 in 2007. Sexual intercourse was the most frequently reported mode of transmission (65%), especially among men having sex with men. Genotypes A and D remained predominant. In total, 40,600 participants were fully vaccinated, the overall compliance was 62%, and the estimated overall program coverage was 12% of the at-risk population. With more effort, more susceptibles may be reached, but the program will not be sufficient to substantially reduce HBV in the Netherlands. Therefore, universal vaccination should be considered.

Evaluation prompting transition from enhanced to routine surveillance of lymphogranuloma venereum (LGV) in the Netherlands.

In 2004, a lymphogranuloma venereum (LGV) epidemic among men who have sex with men in the Netherlands motivated the introduction of enhanced surveillance. We evaluated the acceptability of the enhanced LGV surveillance in the Netherlands in 2004-2005 to provide recommendations for future surveillance. Completeness of requested patient information was analysed. All 12 sexually transmitted infection (STI) health services participating in the 2004-2005 STI surveillance completed evaluation questionnaires and rated surveillance system features from 1="very poor" to 5="very good". Information from enhanced LGV surveillance was available for 34 (33%) of 104 cases. For these 34 cases, median proportions of response decreased successively for clinical information (100%), sexual anamnesis (71%) and details about the last sex partners (44%). A median score of 4 ("good") was assigned to simplicity, required resources and surveillance information requested and distributed. Seven respondents favoured continuation of LGV surveillance, whereof six preferred modifications, usually meaning less extensive surveillance. In conclusion, the enhanced LGV surveillance was generally regarded as adequate. However, it was limited by low completeness, underlining the need to keep requested information to a minimum. The routine STI surveillance now includes LGV diagnosis and, following this evaluation, the additional enhanced surveillance was discontinued. However, occasional cases justify alertness and LGV remains under routine STI surveillance in the Netherlands.

[Hepatitis B virus transmission patterns in the Netherlands, 2004]. / Transmissiepatronen van hepatitis B-virus in Nederland, 2004.

OBJECTIVE: To gain insight into hepatitis B virus (HBV) transmission in the Netherlands. DESIGN: Descriptive. METHOD: During 2004, epidemiological data and blood samples (if available) were collected for all reported cases of acute HBV infections in the Netherlands. Following DNA isolation and amplification a 648 base pairs fragment of the HBV S gene was sequenced and subjected to phylogenetic analysis. The sequencing details were also linked to epidemiological information. RESULTS: In 2004, 291 cases ofacute HBV infections were reported. Blood samples were received from 171 patients (59%), and the genotype could be determined for 158 patients (54%). 6 genotypes were identified: A (64%), B (3%), C (3%), D (21%), E (5%) and F (4%). Of all patients with genotype A, 52% had been infected via homosexual or bisexual contact and 16% via heterosexual contact. Of all patients with genotype D, 42% had been infected via heterosexual contact and 15% via homosexual or bisexual contact. The genotype A cluster was extremely homogeneous with many identical sequences, while genotype B-E clusters were more heterogeneous. 4 identical sequences were found within genotype F, but the patients could not be epidemiologically linked. CONCLUSION: Sexual transmission, particularly via homosexual or bisexual contact in men, formed the most important risk factor for acquiring an acute HBV infection. Genotype A was predominant in the Netherlands, especially among homosexual or bisexual men. Most infections within genotype D occurred as a result of heterosexual contact. The results show that there was ongoing transmission of HBV in homosexual or bisexual men, while in heterosexuals more cases of new introduction were seen, possibly via chronic carriers from areas where HBV is endemic.

[Hepatitis B surveillance in the Netherlands, 2002-2005: acute infection is mainly via sexual contact while chronic infection is via vertical transmission through mothers from endemic regions]. / Surveillance van hepatitis B in Nederland, 2002-2005: acute infectie vooral via seksueel contact, chronische via verticale transmissie door moeders uit endemische gebieden.

OBJECTIVE: To study the trends in the prevalence of hepatitis B infections in the Netherlands on the basis of reported cases. DESIGN: Retrospective, descriptive. METHOD: Analysis of data collected from the obligatory notification of hepatitis B to the Dutch Public Health Services in the Netherlands in the period 2002-2005. RESULTS: In the period from January 2002 to December 2005, 7352 hepatitis B virus (HBV) infections were reported, of which 1168 (16%) were acute and 5849 (80%) were chronic infections. Of the acute HBV infections, 34% were transmitted by homo- or bisexual contact and 25% by heterosexual contact. The number of reports of acute HBV infection due to heterosexual transmission increased significantly and originated relatively more often in Dutch patients. The number of reports of chronic HBV infection in men increased significantly; in women there was a decrease over time. Of the chronic HBV infections, 40% were transmitted from mother to child; this was reported especially often by patients from HBV endemic areas. CONCLUSION: Sexual contact was the most important risk factor for the transmission of acute HBV infections, whereas vertical transmission was the greatest risk factor by far for chronic HBV infection. Transmission via heterosexual contact had become increasingly important in the transmission of acute HBV; transmission by homo- or bisexual contact remained constant. Immigration continued to play an important role in the epidemiology of HBV in the Netherlands; the majority of the chronic carriers had been born and infected in an HBV endemic area.

Molecular epidemiology of acute hepatitis B in the Netherlands in 2004: nationwide survey.

To gain insight into hepatitis B virus (HBV) transmission in the Netherlands, epidemiological data and sera were collected from reported cases of acute HBV infections in the Netherlands in 2004. Cases were classified according to mode of transmission. A fragment of the S-gene of HBV (648 bp) was amplified, sequenced, and subjected to phylogenetic analysis. Of the 291 acute HBV cases reported in 2004, 158 (54%) were available for genotyping. Phylogenetic analysis identified 6 genotypes: A (64%), B (3%), C (3%), D (21%), E (5%) and F (5%). Of HBV infected men having sex with men, 86% were infected with genotype A, accounting for 43% of all patients infected with this genotype. There were only three reported cases of injecting drug use of which one was available for sequencing (genotype A). Unlike the genotype A cluster, sequences within the genotype B-E clusters were heterogenic. Within genotype F, several isolates had identical sequences, but patients could not be epidemiologically linked. Sexual transmission, particularly by men having sex with men was the most important transmission route for HBV. Injecting drug use plays a minor role. Genotype A is predominant in the Netherlands, especially among men having sex with men. In addition to imported strains, there seems to be a pool of related but non-identical strains circulating among chronic carriers in the migrant population, from which occasionally new patients are infected, primarily by heterosexual transmission.

[Further increase of quinolone resistance of gonococci in the Netherlands and proposal for a new surveillance]. / Verdere toename in chinolonresistentie van gonokokken in Nederland en voorstel voor hernieuwde surveillance.

Previous publications have indicated that between 2002 and 2003 in the Netherlands, the antimicrobial resistance in gonococci increased. Repeat measurements in 2004 and 2005 suggest a further increase in resistance ofgonococci, to quinolones in particular, from 7% in 2002 to 26% in 2005. National surveillance of gonococcal antimicrobial resistance is important for public health. In 2006 a further survey will be implemented, in which resistance data and epidemiological information on the patients are combined and collected in a project called 'Gonococcal resistance to antimicrobials surveillance' (GRAS).

A slow epidemic of LGV in the Netherlands in 2004 and 2005.

In 2004, an outbreak of LGV was detected in MSM in the Netherlands. By January 2006, 179 confirmed cases of LGV had been reported; 65 (retrospectively) in 2002/2003, 76 in 2004 and 38 in 2005. The evolution of the LGV outbreak appears to have slowed down and only a few cases were found in the first months of 2006.

HIV and STIs increasing in the Netherlands according to latest surveillance data.

In 2004, numbers of sexually transmitted infections (STIs) increased in the Netherlands compared with 2003.

A slow epidemic of LGV in the Netherlands in 2004 and 2005.

In 2004, an outbreak of LGV was detected in MSM in the Netherlands. By January 2006, 179 confirmed cases of LGV had been reported; 65 (retrospectively) in 2002/2003, 76 in 2004 and 38 in 2005. The evolution of the LGV outbreak appears to have slowed down and only a few cases were found in the first months of 2006.