Catharina J. Alberts

Association of Chlamydia trachomatis infection and herpes simplex virus type 2 serostatus with genital human papillomavirus infection in men: the HPV in men study.

Background Studies in women indicate that some sexually transmitted infections promote human papillomavirus (HPV) persistence and carcinogenesis. Little is known about this association in men; therefore, we assessed whether Chlamydia trachomatis (CT) infection and herpes simplex virus type 2 (HSV-2) serostatus are associated with genital HPV prevalence, an early event in HPV-related pathogenesis. Methods Genital exfoliated cells, first-void urine, and blood from 3971 men recruited in the United States, Mexico, and Brazil were tested for HPV, CT, and HSV-2 antibodies, respectively. Multivariable logistic regression was used to assess the association of CT infection and HSV-2 serostatus with 4 HPV outcomes (any, oncogenic, nononcogenic only, and multiple infections). Results A total of 64 (1.6%) men were CT positive, and 811 (20.4%) men were HSV-2 seropositive. After adjustment for potential confounders, CT was associated with any HPV (adjusted odds ratio [aOR], 2.19; 95% confidence interval [CI], 1.13–4.24), oncogenic HPV (aOR, 3.10; 95% CI, 1.53–6.28), and multiple HPV (aOR, 3.43; 95% CI, 1.69–6.95) prevalence. Herpes simplex virus type 2 serostatus was associated with any HPV (aOR, 1.25; 95% CI, 1.02–1.52), nononcogenic HPV only (aOR, 1.38; 95% CI, 1.08–1.75), and multiple HPV (aOR, 1.33; 95% CI, 1.06–1.68) prevalence. In analyses stratified by sexual behavior, CT infection was significantly associated with HPV detection among men reporting 2 or more recent sexual partners, whereas HSV-2 serostatus was significantly associated with HPV detection in men reporting 0 to 5 lifetime sexual partners. Conclusion In this population, CT infection and HSV-2 serostatus were associated with prevalent genital HPV infection. Future prospective studies should investigate whether these infections influence HPV acquisition and/or persistence.

Route of Sexual Exposure Is Independently Associated With Seropositivity to HPV-16 and HPV-18 Among Clients of an STI Clinic in the Netherlands

We investigated the route of sexual exposure as a determinant for human papillomavirus (HPV)-16 and HPV-18 seropositivity. At the Amsterdam sexually transmitted infections clinic we recruited 4 risk groups: (1) men who have sex with women only (MSW; n = 751); (2) women who have sex with men (WSM; n = 749); (3) men who have sex with men (MSM) reporting insertive anal sex only (insMSM; n = 156); and (4) MSM reporting receptive anal sex (recMSM; n = 415). In multivariable analyses, HPV-16 seropositivity was significantly more common in WSM vs MSW, recMSM vs MSW, and recMSM vs insMSM. HPV-18 results were similar. Route of sexual exposure is independently associated with HPV seropositivity.

The association between ethnicity and vaginal microbiota composition in Amsterdam, the Netherlands

Objective To evaluate whether ethnicity is independently associated with vaginal microbiota (VMB) composition in women living in Amsterdam, the Netherlands, as has been shown for American women. Methods Women (18–34 years, non-pregnant, N = 610) representing the six largest ethnic groups (Dutch, African Surinamese, South-Asian Surinamese, Turkish, Moroccan, and Ghanaian) were sampled from the population-based HELIUS study. Sampling was performed irrespective of health status or healthcare seeking behavior. DNA was extracted from self-sampled vaginal swabs and sequenced by Illumina MiSeq (16S rRNA gene V3-V4 region). Results The overall prevalence of VMBs not dominated by lactobacilli was 38.5%: 32.2% had a VMB resembling bacterial vaginosis and another 6.2% had a VMB dominated by Bifidobacteriaceae (not including Gardnerella vaginalis), Corynebacterium, or pathobionts (streptococci, staphylococci, Proteus or Enterobacteriaceae). The most prevalent VMB in ethnically Dutch women was a Lactobacillus crispatus-dominated VMB, in African Surinamese and Ghanaian women a polybacterial G. vaginalis-containing VMB, and in the other ethnic groups a L. iners-dominated VMB. After adjustment for sociodemographic, behavioral and clinical factors, African Surinamese ethnicity (adjusted odds ratio (aOR) 5.1, 95% confidence interval (CI) 2.1–12.0) and Ghanaian ethnicity (aOR 4.8, 95% CI 1.8–12.6) were associated with having a polybacterial G. vaginalis-containing VMB, and African Surinamese ethnicity with a L. iners-dominated VMB (aOR 2.8, 95% CI 1.2–6.2). Shorter steady relationship duration, inconsistent condom use with casual partners, and not using hormonal contraception were also associated with having a polybacterial G. vaginalis-containing VMB, but human papillomavirus infection was not. Other sexually transmitted infections were uncommon. Conclusions The overall prevalence of having a VMB not dominated by lactobacilli in this population-based cohort of women aged 18–34 years in Amsterdam was high (38.5%), and women of sub-Saharan African descent were significantly more likely to have a polybacterial G. vaginalis-containing VMB than Dutch women independent of modifiable behaviors.

A longitudinal study on determinants of HPV vaccination uptake in parents/guardians from different ethnic backgrounds in Amsterdam, the Netherlands

BackgroundHuman papillomavirus (HPV) vaccination coverage in the Netherlands is low (~60%) compared to other childhood vaccinations (>90%), and even lower among ethnic minorities. The aim of this study was to explore the possible impact of ethnicity on the determinants of both HPV vaccination intention and HPV vaccination uptake among parents/guardians having a daughter that is invited for the HPV vaccination.MethodsIn February 2014, parents/guardians living in Amsterdam were invited to complete a questionnaire about social-psychological determinants of their decision making process regarding the HPV vaccination of their daughter and socio-demographic characteristics. This questionnaire was sent approximately one month before the daughter was scheduled to receive her first HPV vaccine dose. Their daughters’ HPV vaccination status was retrieved from the national vaccination database. We distinguished four ethnic groups: Dutch (NL), Surinamese, Netherlands Antillean, and Aruban (SNA), Middle-Eastern and North-African (MENA), and Other. To assess the impact of determinants on both intention and uptake, linear and logistic regression analyses were used respectively. Missing data were imputed using multiple imputation by chained equation.ResultsIn total 1,309 parents/guardians participated (33% participation rate). In all groups we found the mothers’ intention to be the strongest predictor of their daughters’ HPV vaccination uptake. Explained variance of uptake was highest in the NL-group (pseudo-R2:0.56) and lower in the other ethnic groups (pseudo-R2 varied between 0.23 and 0.29). The lower explained variance can be attributed to the relative large proportion of participants with a positive intention that finally did not go for vaccination in the SNA-group (11%) and MENA-group (30%). Explained variance (R2) of intention varied between 0.66 and 0.77 across ethnic groups, and was best explained by the proximal social-psychological determinants. The strength of association of these determinants with both intention and uptake were largely similar across ethnic groups.ConclusionWe conclude that the same determinants should be targeted in the different ethnic groups, although the mode of delivery of the intervention needs to be tailored to the different cultural backgrounds. Further research is needed to explain the observed discrepancy between intention and uptake, especially among parents/guardians in the non-Dutch groups.

HIV is an important risk factor for human papillomavirus types 16 and 18 seropositivity among sexually active men who have sex with men

Objective The aim of this study was to investigate whether HIV infection is a main risk factor for human papillomavirus (HPV)-16 and HPV-18 seropositivity in men who have sex with men (MSM), and what other risk factors are associated with HPV-16 and HPV-18 seropositivity in this population. Methods Men who have sex with men visiting a sexually transmitted infection (STI) clinic in Amsterdam in 2008 to 2009 answered questions concerning demographics and sexual behavior. Sera were tested for HPV antibodies to the major HPV capsid protein L1 by Luminex-based multiplex serology. As it is known that site of exposure is associated with seropositivity, this analysis was restricted to MSM who reported receptive anal sex during the preceding 6 months. Using multivariable logistic regression, we examined whether HIV was associated with HPV serostatus. Results Included in the study were 415 HIV-negative and 205 HIV-positive MSM reporting receptive anal sex. Median age of the study population was 39 years (interquartile range, 31–44). Human papillomavirus seroprevalence differed significantly between HIV-negative and HIV-positive MSM: 31% versus 65% (P < 0.001) for HPV-16 and 28% versus 51% (P < 0.001) for HPV-18. After adjusting for important risk factors HPV-16 (adjusted odds ratio, 2.80; 95% confidence interval, 1.75–4.49) and HPV-18 (adjusted odds ratio, 1.78; 95% confidence interval, 1.11–2.85), seropositivity was significantly more common in HIV-positive than in HIV-negative MSM. We could not identify other consistent risk factors for HPV-16 and HPV-18 seropositivity. Conclusions HIV infection is an important risk factor for HPV-16 and HPV-18 seropositivity among MSM reporting receptive anal sex in the preceding 6 months.

Vaginal high-risk human papillomavirus infection in a cross-sectional study among women of six different ethnicities in Amsterdam, the Netherlands: the HELIUS study

Objective In the Netherlands the incidence of cervical cancer is higher among ethnic minority populations compared with the general Dutch population. We investigated the prevalence of, and risk factors associated with, vaginal high-risk human papillomavirus (hrHPV) infection in women of six different ethnicities living in Amsterdam. Methods For this cross-sectional study we selected women aged 18–34 years old of six ethnicities from the large-scale multiethnic HEalthy LIfe in an Urban Setting study. Self-collected vaginal swabs were tested for HPV DNA and genotyped using a highly sensitive PCR and reverse line blot assay (short PCR fragment (SPF)10-PCR DNA enzyme immunoassay/LiPA25-system version-1, delft diagnostic laboratory (DDL)). Participants completed a questionnaire regarding demographics and sexual behaviour. Logistic regression using generalised estimating equations was used to assess risk factors of hrHPV, and to investigate whether prevalence of hrHPV differed among ethnicities. Results The study population consisted of 592 women with a median age of 27 (IQR: 23–31) years. Dutch and African Surinamese women reported the highest sexual risk behaviour. HrHPV prevalence was highest in the Dutch (40%) followed by the African Surinamese (32%), Turkish (29%), Ghanaian (26%), Moroccan (26%) and South-Asian Surinamese (18%). When correcting for sexual risk behaviour, the odds to be hrHPV-positive were similar for all non-Dutch groups when compared with that of the Dutch group. Conclusions We found an overall higher hrHPV prevalence and higher sexual risk behaviour in the native Dutch population. Further research is needed to unravel the complex problem concerning cervical cancer disparities, such as differences in participation in the cervical cancer screening programme, or differences in clearance and persistence of hrHPV.

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 (&bgr; = 0.6; 95% CI, 0.5–0.7), descriptive norm (&bgr; = 0.2; 95% CI, 0.1–0.3), self-efficacy (&bgr; = 0.2; 95% CI, 0.1–0.3), beliefs (&bgr; = 0.1; 95% CI, 0.0–0.2), and subjective norm (&bgr; = 0.1; 95% CI, 0.0–0.2) seemed to be the strongest predictors of HPV vaccination intention (R 2 = 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.

High-risk human papillomavirus seroprevalence in men and women of six different ethnicities in Amsterdam, the Netherlands: The HELIUS study

Background Ethnic variations in the (sero)prevalence of Human Papillomavirus (HPV) and HPV related diseases have been observed previously. We explored if high-risk HPV (hrHPV) seropositivity indeed differs among 6 ethnic groups in Amsterdam the Netherlands and assessed if hrHPV seroprevalence is higher among women than men within each ethnic group, both after adjustment for confounders. Methods From the multi-ethnic HEalthy Life In an Urban Setting (HELIUS) study in Amsterdam (the Netherlands) we randomly selected 4637 men and women aged 18–44 years with a Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Moroccan, or Turkish ethnicity. Blood samples were tested for HPV-16,−18,−31,−33,−45,−52, and −58 antibodies using a validated Luminex-based multiplex serology assay. We assessed the association of both ethnicity and gender with hrHPV seropositivity using logistic regression models with generalised estimating equations. Results The hrHPV seroprevalence in Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Moroccan, and Turkish participants was 18%, 12%, 23%, 19%, 17%, and 15% in men, and 30%, 22%, 34%, 31%, 14%, and 15% in women, respectively. HrHPV seroprevalence of non-Dutch men did not differ significantly from Dutch men. HrHPV seroprevalence was significantly higher among African Surinamese women, and significantly lower among Moroccan and Turkish women when compared to Dutch women. These differences were not significant anymore after adjustment for demographic, health, and sexual behavioural differences between ethnicities. HrHPV seroprevalence varied by age, age of sexual debut, and lifetime sexual partners among women but not among men. Seroprevalence of hrHPV was higher among women than among men, except in the Turkish group. Conclusion Among women hrHPV seroprevalence differed by ethnicity, yet among men no pronounced differences were observed across ethnicities.

HPV vaccination intention among male clients of a large STI outpatient clinic in Amsterdam, the Netherlands

We explored HPV vaccination intention and its determinants among male clients of the sexually transmitted infections (STI) clinic in Amsterdam. In 2015, male clients aged ≥18 years were invited to complete a web-based questionnaire regarding HPV vaccination intention and socio-psychological determinants. Determinants (scale −3 to +3) were assessed with linear regression, stratified for men who have sex with men (MSM) (including men who have sex with men and women) and men who only have sex with women (MSW). Additionally, we explored the effect of out-of-pocket payment on intention. Of 1490 participants (median age 33 years [IQR:25–44]), 1,053(71%) were MSM. HPV vaccination intention was high (mean 1.68, 95%CI:1.55–1.81 among MSW; mean 2.35, 95%CI:2.29–2.42 among MSM). In multivariable analyses, socio-psychological determinants had similar effects on intention in both groups (R2=0.70 among MSW; R2=0.68 among MSM), except for subjective norms, self-efficacy, and HPV knowledge (significantly stronger associations among MSW). HPV vaccination intention decreased significantly when vaccination would require out-of-pocket payment; intention was negative at the current list price (€350). HPV vaccination intention among male clients of the Amsterdam STI-clinic is high and variance in intention was mostly be explained by socio-psychological factors. Out-of-pocket payment had a strong negative effect on HPV vaccination intention.

P5.20 Hpv vaccination intention among female sex workers in amsterdam, the netherlands

Introduction Female sex workers (FSW) are at risk for HPV-induced diseases but are currently not targeted by the HPV vaccination program in the Netherlands. We explored the determinants of their intention to get vaccinated against HPV in case vaccination would be offered to them in the near future. Methods In 2016, FSW aged >18 years having an STI consultation with the Prostitution and Health Centre (P and G292) in Amsterdam, either at the clinic or at their working location, were invited to complete a questionnaire assessing the socio-psychological determinants of their HPV vaccination intention (scale ranging from −3 to +3). Determinants of HPV vaccination intention were assessed with uni- and multivariable linear regression. Additionally, we explored the effect of out-of-pocket payment on intention. Results Between May and September 2016, 293 FSW participated; 98 (34%) worked in clubs/private houses/massage salons, 111 (38%) worked at ‘prostitution windows’, and 81 (28%) worked as escorts or from home. The median age was 29 years (IQR 25–37). HPV vaccination intention was relatively high (mean 2.0; 95% CI:1.8–2.2). In multivariable analysis attitude (β=0.6; 95% CI:0.5–0.7), descriptive norm (β=0.3; 95% CI:0.2–0.4), self-efficacy (β=0.2; 95% CI:0.1–0.3), beliefs (β=0.1; 95% CI:0.0–0.2) and anticipated regret (β=0.1; 95% CI:0.0–0.2) were the strongest predictors of HPV vaccination intention. Demographic variables did not improve the multivariable regression model. The explained variance in the model (R2) was 0.54. HPV vaccination intention decreased significantly when vaccination would require out-of-pocket payment (€50 mean: 1.2 (95%CI: 0.8–1.7); €100 mean: 1.6 (95%CI: 1.1–2.0); € 200 mean: 1.0 (95%CI: 0.5–1.5); € 350 mean: 0.2 (95%CI: −0.2–0.7). Conclusion HPV vaccination intention among FSW in Amsterdam appears to be very high. The included socio-psychological factors explained most of the variance in HPV vaccination intention among FSW. Out-of-pocket payment had a significant negative effect on HPV vaccination intention.