A survey-based assessment of rates and covariates of mpox diagnosis and vaccination provides evidence to refine eligibility criteria for mpox vaccination among gay, bisexual and other men who have sex with men in the Netherlands.

Background: The 2022 multicountry mpox outbreaks predominantly affected gay, bisexual and other men who have sex with men (GBMSM) in non-endemic countries, including in the Netherlands. We conducted a survey-based assessment of the alignment between the risk factors associated with mpox diagnosis among GBMSM in the Netherlands and the eligibility criteria used in 2022 for vaccinating this group, with the aim to refine these criteria. Methods: An online self-report survey was conducted among adult GBMSM in the Netherlands between 29 July and 30 August 2022, corresponding to the first month of the Dutch mpox vaccination campaign. GBMSM were recruited via advertisements on social media and gay dating apps. Participants reported on their sexual behaviour, mpox diagnosis, and/or (initial) mpox vaccination since the start of the outbreak. Covariables of mpox diagnosis and vaccination were assessed using logistic regression analyses. Results: Of the 2,460 participants, 73 (3.0%, 95% CI 2.3-3.6%) were diagnosed with mpox and 485 (19.7%, 95% CI 18.1-21.3%) had received (initial) mpox vaccination. Using sample weighting, we estimated that, of the GBMSM population aged 18-80 years in the Netherlands, 1.1% (95% CI 0.7-1.6%) had been diagnosed with mpox and 7.8% (95% CI 6.8-8.9%) had received (initial) vaccination. HIV-PrEP use, living with HIV, reporting ≥20 sex partners in the past 12 months, and sex in sex venues/parties in the past 2 months were independent risk factors for mpox diagnosis. Except for sex in sex venues/parties, these variables were also independently associated with mpox vaccination. Conclusion: This study provides novel evidence regarding the degree to which the 2022 eligibility criteria for mpox vaccination align with the risk factors for mpox among GBMSM in the Netherlands. The findings contribute to a refinement of the eligibility criteria for mpox vaccination, to which sex in sex venues/parties should be added.

Mpox vaccination willingness, determinants, and communication needs in gay, bisexual, and other men who have sex with men, in the context of limited vaccine availability in the Netherlands (Dutch Mpox-survey).

Introduction: In the 2022 multicountry mpox (formerly named monkeypox) outbreak, several countries offered primary preventive vaccination (PPV) to people at higher risk for infection. We study vaccine acceptance and its determinants, to target and tailor public health (communication-) strategies in the context of limited vaccine supply in the Netherlands. Methods: Online survey in a convenience sample of gay, bisexual and other men who have sex with men, including transgender persons (22/07-05/09/2022, the Netherlands). We assessed determinants for being (un)willing to accept vaccination. We used multivariable multinominal regression and logistic regression analyses, calculating adjusted odds ratios (aOR) and 95 percent confidence-intervals. An open question asked for campaigning and procedural recommendations. Results: Of respondents, 81.5% (n = 1,512/1,856) were willing to accept vaccination; this was 85.2% (799/938) in vaccination-eligible people and 77.7% (713/918) in those non-eligible. Determinants for non-acceptance included: urbanization (rural: aOR:2.2;1.2-3.7; low-urban: aOR:2.4;1.4-3.9; vs. high-urban), not knowing mpox-vaccinated persons (aOR:2.4;1.6-3.4), and lack of connection to gay/queer-community (aOR:2.0;1.5-2.7). Beliefs associated with acceptance were: perception of higher risk/severity of mpox, higher protection motivation, positive outcome expectations post vaccination, and perceived positive social norms regarding vaccination. Respondents recommended better accessible communication, delivered regularly and stigma-free, with facts on mpox, vaccination and procedures, and other preventive options. Also, they recommended, "vaccine provision also at non-clinic settings, discrete/anonymous options, self-registration" to be vaccinated and other inclusive vaccine-offers (e.g., also accessible to people not in existing patient-registries). Conclusion: In the public health response to the mpox outbreak, key is a broad and equitable access to information, and to low-threshold vaccination options for those at highest risk. Communication should be uniform and transparent and tailored to beliefs, and include other preventive options. Mpox vaccine willingness was high. Public health efforts may be strengthened in less urbanized areas and reach out to those who lack relevant (community) social network influences.

Chlamydia trachomatis, Neisseria gonorrhoea, and Trichomonas vaginalis infections among pregnant women and male partners in Dutch midwifery practices: prevalence, risk factors, and perinatal outcomes.

BACKGROUND: Antenatal screening for HIV, syphilis and HBV has been successfully implemented in The Netherlands, but data on other STI among pregnant women or male partners are limited. Our objectives: (i) to assess the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) among pregnant women and male partners, (ii) to identify risk factors for these STI during pregnancy, and (iii) to identify adverse perinatal outcomes (APO) associated with STI. METHODS: Cross-sectional study. Pregnant women aged ≤ 30 years (n = 548) and male partners (n = 425) were included at 30 midwifery practices during 2012-2016. Participants provided a self-collected vaginal swab (women) or urine sample (men) and completed a questionnaire. Perinatal data were derived from pregnancy cards. APO was defined as premature rupture of membranes, preterm delivery, low birthweight, stillbirth, neonatal conjunctival and respiratory infections. Data were analysed by logistic regression. RESULTS: STI were present in 2.4% of pregnant women (CT 1.8%, NG 0.4%, TV 0.4%), and in 2.2% of male partners (CT 2.2%, NG 0.2%, TV 0%). Of young women (≤ 20 years), 12.5% had a CT infection. Prevalent STI during pregnancy was associated with female young age (≤ 20 years vs ≥ 21 years) (adjusted OR 6.52, CI 95%: 1.11-38.33), male non-Western vs Western background (aOR 9.34, CI 2.34-37.21), and female with ≥ 2 sex partners < 12 months vs 0-1 (aOR 9.88, CI 2.08-46.91). APO was not associated with STI, but was associated with female low education (aOR 3.36, CI 1.12-10.09), complications with previous newborn (aOR 10.49, CI 3.21-34.25 vs no complications) and short duration (0-4 years) of relationship (aOR 2.75, CI 1.41-5.39 vs ≥ 5 years). Small-for-gestational-age was not associated with STI, but was associated with female low education (aOR 7.81, 2.01-30.27), female non-Western background (aOR 4.41, 1.74-11.17), and both parents smoking during pregnancy (aOR 2.94, 1.01-8.84 vs both non-smoking). CONCLUSIONS: Prevalence of STI was low among pregnant women and male partners in midwifery practices, except for CT among young women. The study could not confirm previously observed associations between STI and APO, which is probably due to low prevalence of STI, small study sample, and presumed treatment for STI.

Antenatal screening for HIV, syphilis and HBV has been successfully implemented in The Netherlands, but data on other STI among pregnant women or male partners are limited. Our objectives were: (i) to assess the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) among pregnant women and male partners, (ii) to identify risk factors for these STI during pregnancy, and (iii) to identify adverse perinatal outcomes (APO) associated with STI.Pregnant women aged ≤ 30 years and male partners were included at 30 midwifery practices. Women provided a vaginal swab, partners a urine sample; both completed a questionnaire. Perinatal data were derived from midwives.STI were present in 2.4% of pregnant women (CT 1.8%, NG 0.4%, TV 0.4%), and in 2.2% of male partners (CT 2.2%, NG 0.2%, TV 0%). Of women ≤ 20 years, 12.5% had a CT infection. Prevalent STI during pregnancy was associated with female young age, male non-Western background, and female with ≥ 2 sex partners < 12 months. APO was not associated with STI, but was associated with female low education, complications with previous newborn, and short duration of the relationship. Small-for-gestational-age was not associated with STI, but was associated with female low education, female non-Western background, and both parents smoking during pregnancy.Prevalence of STI was low among pregnant women and male partners in midwifery practices, except for CT among young women. The study could not confirm previously observed associations between STI and APO. Probably due to low prevalence of STI, small study sample, and presumed treatment for STI.

Monitoring Recently Acquired HIV Infections in Amsterdam, The Netherlands: The Attribution of Test Locations.

Background: Surveillance of recent HIV infections (RHI) using an avidity assay has been implemented at Dutch sexual health centres (SHC) since 2014, but data on RHI diagnosed at other test locations is lacking. Setting: Implementation of the avidity assay in HIV treatment clinics for the purpose of studying RHI among HIV patients tested at different test locations. Methods: We retrospectively tested leftover specimens from newly diagnosed HIV patients in care in 2013-2015 in Amsterdam. Avidity Index (AI) values ≤0.80 indicated recent infection (acquired ≤6 months prior to diagnosis), and AI > 0.80 indicated established infection (acquired >6 months prior to diagnosis). An algorithm for RHI was applied to correct for false recency. Recency based on this algorithm was compared with recency based on epidemiological data only. Multivariable logistic regression analysis was used to identify factors associated with RHI among men who have sex with men (MSM). Results: We tested 447 specimens with avidity; 72% from MSM. Proportions of RHI were 20% among MSM and 10% among heterosexuals. SHC showed highest proportions of RHI (27%), followed by GPs (15%), hospitals (5%), and other/unknown locations (11%) (p < 0.001). Test location was the only factor associated with RHI among MSM. A higher proportion of RHI was found based on epidemiological data compared to avidity testing combined with the RHI algorithm. Conclusion: SHC identify more RHI infections compared to other test locations, as they serve high-risk populations and offer frequent HIV testing. Using avidity-testing for surveillance purposes may help targeting prevention programs, but the assay lacks robustness and its added value may decline with improved, repeat HIV testing and data collection.

HCV micro-elimination in individuals with HIV in the Netherlands 4 years after universal access to direct-acting antivirals: a retrospective cohort study.

BACKGROUND: In the Netherlands, access to direct-acting antivirals (DAAs) against hepatitis C virus (HCV) has been unrestricted for chronic infection since 2015. We evaluated whether the nationwide incidence of HCV infections in individuals with HIV has changed since 2015. METHODS: In this retrospective cohort study, data from the ATHENA cohort of people with HIV aged 18 years or older attending any of the 24 HIV treatment centres in the Netherlands between 2000 and 2019 were assessed. We used parametric proportional hazards models with a piecewise exponential survival function to model HCV primary infection and reinfection incidence per 1000 person-years. FINDINGS: Of the 23 590 individuals without previous HCV infection, 1269 cases of HCV primary infection were documented (incidence 5·2 per 1000 person-years [95% CI 5·0-5·5]). The highest incidence was observed in men who have sex with men (MSM; 7·7 per 1000 person-years [7·3-8·2]) and was lower in people who inject drugs (PWID; 1·7 per 1000 person-years [0·7-4·1]) and other key populations (1·0 per 1000 person-years [0·8-1·2]). In MSM, incidence increased in 2007 to 14·3 per 1000 person-years and fluctuated between 8·7 and 13·0 per 1000 person-years from 2008 to 2015. In 2016, incidence declined to 6·1 cases per 1000 person-years and remained steady between 4·1 and 4·9 per 1000 person-years from 2017 to 2019. Of the 1866 individuals with a previous HCV infection, 274 reinfections were documented (incidence 26·9 per 1000 person-years [95% CI 23·9-30·3]). The highest incidence rate was observed in MSM (38·5 per 1000 person-years [33·9-43·7]) and was lower in PWID (10·9 per 1000 person-years [3·5-33·8]) and other key populations (8·9 per 1000 person-years [6·3-12·5]). In MSM, reinfection incidence fluctuated between 38·0 and 88·9 per 1000 person-years from 2006 to 2015, reaching 55·6 per 1000 person-years in 2015. In 2016, reinfection incidence declined to 41·4 per 1000 person-years, followed by further decreases to 24·4 per 1000 person-years in 2017 and 11·4 per 1000 person-years in 2019. INTERPRETATION: The sharp decline in HCV incidence in MSM with HIV shortly after restrictions on DAAs were lifted suggests a treatment-as-prevention effect. HCV incidence was already low in PWID and other groups before unrestricted access. Ongoing HCV transmission is occurring in MSM, as illustrated by a declining but high rate of reinfection, stressing the need for additional preventive measures. FUNDING: Dutch Ministry of Health, Welfare, and Sport.

Impact of frequent testing on the transmission of HIV and N. gonorrhoeae among men who have sex with men: a mathematical modelling study.

OBJECTIVES: To investigate the impact and efficiency of combined testing for HIV and other STIs on HIV and STI transmission among men who have sex with men (MSM) and to assess what subgroups of MSM should be targeted for frequent testing. METHODS: We developed an agent-based transmission model that simulates infection with HIV or Neisseria gonorrhoeae (NG) among MSM. We examined scenarios with increased percentages of MSM getting tested six monthly, among all MSM or only specific subgroups of MSM (defined according to recent gonorrhoea, number of partners and engagement in condomless anal intercourse (CAI)) and scenarios with reduced intervals between HIV/STI tests. RESULTS: The most efficient strategies were those with increased percentage of MSM getting tested every 6 months among MSM with a recent gonorrhoea diagnosis; or among MSM who had CAI and ≥10 partners; or MSM who had ≥10 partners. Over 10 years, these strategies resulted in 387-718 averted HIV infections and required 29-164 additional HIV tests per averted HIV infection or one to seven additional gonorrhoea tests per averted NG infection. The most effective strategy in reducing HIV transmission was the one where the intervals between tests were reduced by half, followed by the strategy with increased percentage of MSM getting tested every 6 months among all MSM. Over 10 years, these strategies resulted in 1362 and 1319 averted HIV infections, but required 663 and 584 additional HIV tests per averted HIV infection, respectively. CONCLUSIONS: Targeting MSM with recent gonorrhoea diagnosis or MSM with many partners is efficient in terms of HIV/STI tests needed to prevent new HIV or NG infections. Major reductions in HIV incidence can be achieved with consistent HIV/STI testing every 6 months among larger groups, including low-risk MSM. To impede HIV transmission, frequent testing should be combined with other prevention measures.

Evaluating progress towards triple elimination of mother-to-child transmission of HIV, syphilis and hepatitis B in the Netherlands.

BACKGROUND: In 2014 the World Health Organisation (WHO) established validation criteria for elimination of mother-to-child transmission (EMTCT) of HIV and syphilis. Additionally, the WHO set targets to eliminate hepatitis, including hepatitis B (HBV). We evaluated to what extent the Netherlands has achieved the combined WHO criteria for EMTCT of HIV, syphilis and HBV. METHODS: Data of HIV, syphilis and HBV infections among pregnant women and children (born in the Netherlands with congenital infection) for 2009-2015, and data required to validate the WHO criteria were collected from multiple sources: the antenatal screening registry, the HIV monitoring foundation database, the Perinatal Registry of the Netherlands, the national reference laboratory for congenital syphilis, and national HBV notification data. RESULTS: Screening coverage among pregnant women was > 99% for all years, and prevalence of HIV, syphilis and HBV was very low. In 2015, prevalence of HIV, syphilis and HBV was 0.06, 0.06 and 0.29%, respectively. No infections among children born in the Netherlands were reported in 2015 for all three diseases, and in previous years only sporadic cases were observed In 2015, treatment of HIV positive pregnant women was 100% and HBV vaccination of children from HBV positive mothers was > 99%. For syphilis, comprehensive data was lacking to validate WHO criteria. CONCLUSIONS: In the Netherlands, prevalence of maternal HIV, syphilis and HBV is low and congenital infections are extremely rare. All minimum WHO criteria for validation of EMTCT are met for HIV and HBV, but for syphilis more data are needed to prove elimination.

Trends in human immunodeficiency virus diagnoses among men who have sex with men in North America, Western Europe, and Australia, 2000-2014.

PURPOSE: The aim of the article was to investigate recent trends in human immunodeficiency virus (HIV) diagnosis rates among men who have sex with men (MSM) in high-income countries in North America, Western Europe, and Australia. METHODS: Data on annual rates of HIV diagnoses among MSM aged 15 to 65 years from 2000 to 2014 were collected from 13 high-income countries. Joinpoint regression software was used to empirically determine country-specific trend periods. Trends in HIV diagnosis rates and in the proportion of diagnoses occurring in young MSM aged 15 to 24 years were analyzed using Poisson regression and log-binomial regression, respectively. RESULTS: Six countries experienced an increasing trend from 2000 to 2007-08 followed by either a stable or declining trend through 2014. Five countries had recently increasing trends, and two countries had one stable trend from 2000 to 2014. All 13 countries experienced increases in the proportion of diagnoses occurring in young MSM. CONCLUSIONS: Since 2008, half of the 13 high-income countries examined experienced stable or decreasing trends. Still, some countries continue to experience increasing HIV trends, and young MSM are increasingly represented among new diagnoses. Efforts to support early sexual health promotion, reduce barriers to pre-exposure prophylaxis, and improve care engagement for young MSM are critical to addressing current HIV trends.

Comparing viral load metrics and evaluating their use for HIV surveillance.

OBJECTIVES: To investigate the value of in-care viral load (ICVL) and other viral load (VL) metrics for HIV surveillance by comparing time trends and associations with numbers of new HIV diagnoses. METHODS: Data from 20,740 HIV patients registered in the Dutch ATHENA-cohort between 2002 and 2013 were used. We compared: six ICVL metrics (i.e. mean of the mean/first/last/highest log VL, median of the median log VL, first log VL for newly diagnosed combined with mean log VL for all others), log VL at diagnosis, proportion of patients with transmission risk (>400 copies/ml) or suppressed VL (≤200 copies/ml). Subgroup differences were assessed using Kruskal-Wallis and chi-square tests. Negative binomial regression was used for studying associations between VL metrics and numbers of new diagnoses 1-4 years later. RESULTS: Most ICVL metrics showed similar decreasing trends over time. Differences in covariables were found for all VL metrics. Mean ICVL showed the strongest association with new diagnoses: a decrease of one log unit in mean ICVL was associated with a 21% decrease in new diagnoses two years later. CONCLUSIONS: VL metrics may be of value for enhancing HIV surveillance by identifying subgroup differences in impact of treatment on viral suppression, and by predicting numbers of new diagnoses in subsequent years.

Chlamydia screening and prophylactic treatment in termination of pregnancy clinics in the Netherlands and Great Britain: a qualitative study.

BACKGROUND: Women having a termination of pregnancy (TOP) have higher rates of Chlamydia trachomatis (CT) than the general population. In this study, we explored CT treatment and prevention in Dutch TOP clinics in comparison to that provided in Great Britain (GB). METHODS: A qualitative study including 14 semi-structured interviews with health care professionals (HCPs) in TOP clinics (the Netherlands: 9, GB: 5). Interviews were recorded, transcribed, and analysed by thematic content analysis. RESULTS: Prophylactic treatment with azithromycin is routinely prescribed after surgical TOP, but not after medical TOP ('abortion pill'). Sexually transmitted infections (STI) tests are offered to clients who are considered at high risk of having STI. Uptake varies according to health insurance coverage of STI testing. Some Dutch clinics are able to provide free testing for women under 25 years of age. Sexual health counselling is often limited to discussing birth control. The major difference between the Netherlands and GB is that GB TOP clinics more often offer free STI testing and prophylaxis to their clients. CONCLUSION: HCPs in Dutch TOP clinics consider STI testing an important part of their service, but financial barriers prevent testing on location. Dutch TOP clinics should offer STI tests to all women, and collaboration with public health services could improve STI testing and counselling for young people. Furthermore, clinics should treat all TOP clients with prophylactic azithromycin. This could prevent CT and other upper genital tract post-abortion infections.

Factors associated with presenting late or with advanced HIV disease in the Netherlands, 1996-2014: results from a national observational cohort.

OBJECTIVES: Early testing for HIV and entry into care are crucial to optimise treatment outcomes of HIV-infected patients and to prevent spread of HIV. We examined risk factors for presentation with late or advanced disease in HIV-infected patients in the Netherlands. METHODS: HIV-infected patients registered in care between January 1996 and June 2014 were selected from the ATHENA national observational HIV cohort. Risk factors for late presentation and advanced disease were analysed by multivariable logistic regression. Furthermore, geographical differences and time trends were examined. RESULTS: Of 20,965 patients, 53% presented with late-stage HIV infection, and 35% had advanced disease. Late presentation decreased from 62% (1996) to 42% (2013), while advanced disease decreased from 46% to 26%. Late presentation only declined significantly among men having sex with men (MSM; p <0.001), but not among heterosexual males (p=0.08) and females (p=0.73). Factors associated with late presentation were: heterosexual male (adjusted OR (aOR), 1.59; 95% CI 1.44 to 1.75 vs MSM), injecting drug use (2.00; CI 1.69 to 2.38), age ≥ 50 years (1.46; CI 1.33 to 1.60 vs 30-49 years), region of origin (South-East Asia 2.14; 1.80 to 2.54, sub-Saharan Africa 2.11; 1.88 to 2.36, Surinam 1.59; 1.37 to 1.84, Caribbean 1.31; 1.13 to 1.53, Latin America 1.23; 1.04 to 1.46 vs the Netherlands), and location of HIV diagnosis (hospital 3.27; 2.94 to 3.63, general practitioner 1.66; 1.50 to 1.83, antenatal screening 1.76; 1.38 to 2.34 vs sexually transmitted infection clinic). No association was found for socioeconomic status or level of urbanisation. Compared with Amsterdam, 2 regions had higher adjusted odds and 2 regions had lower odds of late presentation. Results were highly similar for advanced disease. CONCLUSIONS: Although the overall rate of late presentation is declining in the Netherlands, targeted programmes to reduce late HIV diagnoses remain needed for all risk groups, but should be prioritised for heterosexual males, migrant populations, people aged ≥ 50 years and certain regions in the Netherlands.

Comparing databases: determinants of sexually transmitted infections, HIV diagnoses, and lack of HIV testing among men who have sex with men.

BACKGROUND: Early detection and treatment of STI/HIV are public health priorities. Our objective was to compare characteristics of men who have sex with men (MSM) in Dutch data available in 2010 from EMIS, an international internet survey, Schorer Monitor, a Dutch internet survey, and data from STI- clinic visits, since these might be subject to different and unknown biases. METHODS: Data from Dutch MSM Internet Surveys (EMISNL N = 3,787; Schorer Monitor, SMON N = 3,602), and 3,800 STI clinic visits (SOAP) were combined into one dataset. We included factors that were measured in all three databases. The socio-demographics included were age (at the time of the survey), zip code, and ethnicity. Behavioural variables included were the number of sexual partners, condom use with last sexual partner, drug use, being diagnosed with STI, being diagnosed with HIV, and HIV testing. Outcomes we investigated were being diagnosed with STI, HIV, and never been tested for HIV. RESULTS: Logistic regressions showed that determinants for being diagnosed with STI were having more sexual partners, drug use, and having had an HIV test (aORs 1.3 to 17.1) in EMIS and SMON. Determinants for being diagnosed with HIV in all three databases were older age, living in Amsterdam, and having more partners (aORs 1.8 to 4.4). In EMIS and SMON, drug use, non-condom use, and having STI were additional determinants (aORs 1.6 to 8.9). Finally, determinants associated with never been tested for HIV were being younger (only SOAP), living outside of Amsterdam, having fewer partners, no drug use, and no STI (aORs 0.2 to 0.8). CONCLUSIONS: Risk factors from internet surveys were largely similar, but differed from STI clinics, possibly because it involves self-reports rather than diagnoses or because of differences in timing. The difference between the internet surveys and STI clinic data is much less pronounced for having never been tested, suggesting both are appropriate for this outcome. These findings shed light on conclusions drawn from different data sources, as well as the comparability of recruitment strategies, the robustness of risk factors, consequences of phrasing questions differently, and on (policy) implications based on different data sources.

Changing Patterns of Undiagnosed HIV Infection in the Netherlands: Who Benefits Most from Intensified HIV Test and Treat Policies?

OBJECTIVES: To estimate HIV prevalence, the number of people living with HIV/AIDS (PLWHA) and the undiagnosed proportion in the Netherlands for 2012, and to compare these with published 2007 estimates. DESIGN: Synthesis of all available data sources. METHODS: Multi-Parameter Evidence Synthesis (MPES) was used to obtain estimates in mutually exclusive key populations at higher risk in three geographical regions (Amsterdam, Rotterdam, rest of the Netherlands). Data sources included HIV prevalence surveys, diagnoses at STI clinics, and registered cases in HIV care. Group specific estimates were reported as Bayesian posterior medians and 95% credible intervals (CrI). RESULTS: The 2012 model estimated 24,350 PLWHA (95% CrI 20,420-31,280) aged 15-70 years; 2,906 (+14%) more than in 2007. The estimated population HIV prevalence was 0.20% (95% CrI 0.17-0.26%). The overall proportion of undiagnosed HIV was lower in 2012 (34%, 95% CrI 22-49%) compared to 2007 (40%, 95% CrI 25-55%). After MSM, migrants from sub-Saharan Africa and the Caribbean formed the largest groups of PLWHA, but proportions of undiagnosed HIV remained high in these groups, 48% and 44% respectively. Amsterdam had lowest proportions undiagnosed for most key populations at higher risk, including MSM and migrants. CONCLUSIONS: In 2012, the number of PLWHA was higher compared to 2007, while the proportion of undiagnosed HIV was lower, especially among MSM. Higher HIV testing rates, earlier treatment, and an improved life expectancy may explain these differences. HIV interventions need to be expanded in all key populations at higher risk, with special focus on migrants and key populationsliving outside of Amsterdam.

Chlamydia screening is not cost-effective at low participation rates: evidence from a repeated register-based implementation study in The Netherlands.

OBJECTIVE: In three pilot regions of The Netherlands, all 16-29 year olds were invited to participate in three annual rounds of Chlamydia screening. The aim of the present study is to evaluate the cost-effectiveness of repeated Chlamydia screening, based on empirical data. METHODS: A mathematical model was employed to estimate the influence of repeated screening on prevalence and incidence of Chlamydial infection. A model simulating the natural history of Chlamydia was combined with cost and utility data to estimate the number of major outcomes and quality-adjusted life-years (QALYs) associated with Chlamydia. Six screening scenarios (16-29 years annually; 16-24 years annually; women only; biennial screening; biennial screening women only; screening every five years) were compared with no screening in two sexual networks, representing both lower ('national network') and higher ('urban network') baseline prevalence. Incremental cost-effectiveness ratios (ICERs) for the different screening scenarios were estimated. Uncertainty and sensitivity analyses were performed. RESULTS: In all scenarios and networks, cost per major outcome averted are above €5000. Cost per QALY are at least €50,000. The default scenario as piloted in the Netherlands was least cost-effective, with ICERs of €232,000 in the national and €145,000 in the urban sexual network. Results were robust in sensitivity analyses. CONCLUSIONS: It is unlikely that repeated rounds of Chlamydia screening will be cost-effective. Only at high levels of willingness to pay for a QALY (>€50,000) screening may be more cost-effective than no screening.

Chlamydia test results were associated with sexual risk behavior change among participants of the Chlamydia screening implementation in The Netherlands.

OBJECTIVE: To examine the effect of a laboratory-confirmed Chlamydia trachomatis (Ct) test result on subsequent sexual risk behavior in a large population-based screening program. METHODS: The study population consisted of 16- to 29-year-old participants of the Chlamydia Screening Implementation who completed Ct testing and questionnaires in 2 or more rounds. The influence of a Ct test result on sexual behavior was analyzed by generalized estimating equation models, in which the Ct test result of the previous round was the independent variable and 1 of the 8 sexual risk behavior indicators was the dependent variable, adjusted for covariates. RESULTS: Of 48,910 Chlamydia Screening Implementation participants with completed questionnaires and test results, 14.1% (n = 6802) and 2.6% (n = 1272) completed 2 and 3 rounds, respectively, and were included in this study. Analysis showed that Ct positives less often reported to "never" use condoms with a casual partner (%change pretest/posttest = -5.7% [-10.3 to -0.9]), whereas Ct negatives less often reported to "always" use condoms with a casual partner (-4.6% [-6.4 to -2.8]; odds ratio [95% confidence interval], 1.75 [1.09 to 2.80]). Ct positives also had more sexual partners in the subsequent round than did participants with a Ct-negative test result (relative risk [95% confidence interval], 1.14 [1.01 to 1.29]). CONCLUSIONS: Ct test results were associated with subsequent sexual risk behavior. In general, Ct positives were more likely to change their behavior after a Ct test result in a more positive and protective direction than Ct negatives, who were more likely to change their behavior toward more risky behavior. Effects over time after a Ct test should be investigated further, especially in the Ct negatives.

Do sexual risk behaviour, risk perception and testing behaviour differ across generations of migrants?

BACKGROUND: Behaviour and related health outcomes of migrants have been suggested to shift towards the practices of the indigenous population of the host country. To investigate this, we studied generational differences in sexual behaviour between first- and second-generation migrants (FGMs and SGMs) in The Netherlands. METHODS: In 2003-05, persons aged 16-70 years with origins in Surinam, the Antilles and Aruba were interviewed on their sexual behaviour in The Netherlands and their country of origin. The relationship of generation, age at migration and sexual behaviour was studied by multinomial logistic regression analyses. RESULTS: Generational differences were observed regarding concurrent partnerships, anal sex and history of sexually transmitted infection. Compared with FGMs who migrated at an age >25 years, those who migrated between 10 and 25 years of age were more likely to report concurrency [odds ratio (OR): 1.52, 95% confidence interval (CI): 1.14-2.04], whereas SGMs were less likely to report concurrency (OR: 0.65, 95% CI: 0.43-0.98). FGMs who migrated before the age of 10 were more likely to have had anal sex (OR: 1.90, 95% CI: 1.34-2.71) or a sexually transmitted infection diagnosis (OR: 1.80, 95% CI: 1.20-2.71) than those who had migrated at >25 years of age. CONCLUSION: Our study shows that not only SGMs but also FGMs who migrated at an early age tend to differ from the sexual patterns of FGMs who migrated at an older age. Generational differences in sexual behaviour could be explained by acculturation and increased identity with the values of the host country.

With whom did you have sex? Evaluation of a partner notification training for STI professionals using motivational interviewing.

OBJECTIVE: To enhance partner notification (PN) practices in Dutch STI clinics, a PN training using motivational interviewing as core strategy was offered to STI professionals and evaluated. METHODS: The effectiveness of PN training on professionals' attitude, self-efficacy, skills and behavior toward PN, was examined using within-subject and between-subject comparison. Before the training and at three months follow-up, a questionnaire was completed by the intervention group (n=54) and a non-random control group (n=37). RESULTS: In the within-subject comparison, positive changes were observed in self-efficacy, skills, and PN behaviors (all p<.05), but not in attitudes toward PN. When we examined differences in change-scores between the intervention and control group, self-efficacy was no longer significant. CONCLUSION: The PN training significantly improved PN skills and -behavior, but had no effect on professionals' attitudes or self-efficacy toward PN. The selection of a convenience control sample seems to offer a more rigorous test of hypotheses than pre-post evaluation only. PRACTICE IMPLICATIONS: The beneficial effect of PN training of STI professionals seems to support a wider roll-out of the training to all STI clinics in the Netherlands, although effects on the number of partners notified and transmissions prevented need to be examined in future research.

[Pre-exposure prophylaxis for the prevention of sexual HIV transmission; new preventative strategy using tenofovir/emtricitabine]. / Pre-expositieprofylaxe van seksuele hiv-transmissie; nieuwe preventiestrategie met tenofovir/emtricitabine.

The Netherlands has approximately 20,000 registered HIV-infected patients. The current HIV prevention policy consisting of condom use and active HIV testing does not effectively mitigate the HIV epidemic in all risk groups. In July of 2012, tenofovir/emtricitabine (TDF/FTC) was approved by the American Food and Drug Administration (FDA) for pre-exposure prophylaxis (PrEP) for long-term use in persons who exhibit frequent risky and unsafe sexual behaviour. With once-daily use and good therapy compliance, TDF/FTC has proved to be effective as PrEP, and few side effects are reported. Drawbacks in the use of TDF/FTC as PrEP are the potential risk of viral resistance and reduced condom use, the relatively high cost and the intensive counselling required. In special cases, long-term PrEP could enhance the current Dutch preventive policy. Further research is needed into the practical feasibility and protective efficacy of the ad hoc use of TDF/FTC as PrEP before a high-risk contact occurs.