Site-specific human papillomavirus infection in adolescent men who have sex with men (HYPER): an observational cohort study

Methodological Approaches for Incorporating Marginalized Populations into HPV Vaccine Modeling: A Systematic Review

Background. Delineation of historically marginalized populations in decision models can identify strategies to improve equity but requires assumptions in both model structure and stratification of input data. Purpose. We sought to characterize alternative methodological approaches for incorporating marginalized populations into human papillomavirus (HPV) vaccine decision-support models. Data Sources. We conducted a systematic search of PubMed, CINAHL, Scopus, and Embase from January 2006 through June 2022. Study Selection. We identified simulation models of HPV vaccination that refine any model input to specifically reflect a marginalized population. Data Extraction. We extracted data on key methodological decisions across modeling approaches to incorporate marginalized populations, including stratification of inputs, model structure, attribution of prevaccine disparities, calibration, validation, and sensitivity analyses. Data Synthesis. We identified 30 models that stratified inputs by sexual behavior (i.e., men who have sex with men), HIV infection status, race, ethnicity, income, rurality, or combinations of these. We identified 5 common approaches used to incorporate marginalized groups. These included models based primarily on differences in sexual behavior (k = 6), HPV cancer incidence (k = 10), cancer screening and care access (k = 4), and HPV natural history (through either direct incorporation of data [k = 10] or calibration [k = 5]). Few models evaluated sensitivity around their conceptualization of the marginalized group, and only 5 models validated outcomes for the marginalized group. Limitations. Evaluated studies reflected a variety of settings and research questions, making it difficult to evaluate the implications of differences across modeling approaches. Conclusions. Modelers should be explicit about the assumptions and theory driving their model structure and input parameters specific to key marginalized populations, such as the causes of prevaccination differences in outcomes. More emphasis is needed on model validation and rigorous sensitivity analysis.HighlightsWe identified 30 unique HPV vaccination models that incorporated marginalized populations, including populations living with HIV, low-income or rural populations, and individuals of a marginalized race, ethnicity, or sexual behavior.Methods for incorporating these populations, as well as the assumptions inherent in the modeling structure and parameter selections, varied substantially, with models explicitly or implicitly attributing prevaccine differences to alternative combinations of biological, behavioral, and societal mechanisms.Modelers seeking to incorporate marginalized populations should be transparent about assumptions underlying model structure and data and examine these assumptions in sensitivity analysis when possible.

Infection and Persistent Infection of Human Papillomavirus Among HIV-Negative Men Who Have Sex with Men in Xinjiang, China: A Prospective Cohort Study

Anal HPV infection is particularly prevalent among men who have sex with men (MSM). The purpose of this study was to understand the status and influencing factors of HPV infection in MSM in Urumqi, Xinjiang, in order to provide suggestions for policy formulation. A prospective cohort study was conducted among HIV-negative MSM in Urumqi Xinjiang between April 2016 and June 2023. 824 MSM were recruited. Data were collected anal swab results from self-administered questionnaires and laboratory tests. A Cox regression model was employed to analyze factors associated with HPV infection. The prevalence rates of high-risk HPV and low-risk HPV were 37.99% and 25.97%. Receptive anal intercourse is a well-established risk factor for both incident and persistent HPV infections among MSM. For new high-risk HPV infections, the adjusted hazard ratio is 1.55 (95% CI: 1.28-1.89), and for persistent high-risk HPV infections, the aHR is 1.95 (95% CI: 1.48-2.57). Similarly, for low-risk HPV, receptive anal intercourse increases the risk of incidence (aHR = 1.34, 95% CI: 1.07-1.67) and persistent infection (aHR = 1.64, 95% CI: 1.18-2.29). Seeking sexual partners in bathhouses raised the risk of low-risk HPV infections (aHR = 1.36, 95% CI: 1.05-1.76). Young MSM may face a higher risk of HPV infection. Implementing targeted HPV vaccination catch-up programs for the MSM population in Urumqi could offer significant societal benefits.

Clearance of anal and penile HPV 6, 11, 16, and 18 DNA and antibodies among adolescent men who have sex with men (HYPER): An observational cohort study

Background

Clearance of human papillomavirus (HPV) among adolescent men who have sex with men (MSM) is not well studied. This study aimed to evaluate the clearance of HPV DNA and antibodies among adolescent MSM.

Methods

In our cohort study, we enrolled adolescent MSM in Melbourne between October 2010 and September 2013. At baseline, 3, 6, and 12 months, anal and penile swabs for HPV DNA and serum for HPV antibodies against genotypes 6, 11, 16, and 18, were collected. Definite clearance was defined as HPV DNA (same site) /antibodies for the same genotype undetected following a positive HPV DNA /antibodies test at baseline or month 3. Possible clearance was defined as HPV DNA (same site) /antibodies for the same genotype undetected at month 12 following a positive HPV DNA/antibodies test at month 6. Overall clearance was defined as either definite or possible clearance. The agreement between HPV DNA clearance and antibodies clearance was calculated.

Results

A total of 183 MSM were included (median age: 19 years, interquartile [IQR]: 18 to 20). At the anus, overall clearance rate was 21.6 (95 % confidence interval[CI]: 7.9 to 47.0), 44.8 (19.3 to 88.3), 51.9 (20.9 to 106.9) and 33.7 (7.0 to 98.5) per 1000 person months (PM) for HPV 6, 11, 16 and 18. At the penis, overall clearance rate was 64.5 (13.3 to 188.5), 71.3 (14.7 to 208.2), 96.5 (31.3 to 225.3) and 333.3 (8.4 to 1857.2) per 1000 PM for HPV 6, 11, 16 and 18. For antibodies, overall clearance rate was 22.2 (9.6 to 43.7), 18.8 (3.9 to 55.0), 10.8 (0.3 to 60.1) and 19.0 (2.3 to 68.8) per 1000 PM. Agreement between anal/penile HPV DNA clearance and antibodies clearance was low: kappa = -0.18 (95 % CI: -0.28 to 0.08)/-0.13 (-0.24 to -0.02), 0.04 (-0.29 to 0.36)/0.22 (-0.32 to 0.76), -0.10 (-0.27 to 0.08)/-0.14 (-0.37 to 0.10) and -0.14 (-0.28 to 0.01)/-0.14 (-0.33 to 0.06) for HPV 6, 11, 16 and 18, respectively.

Conclusion

Clearance rates of HPV DNA were low and varied by genotypes and anatomical sites among adolescent MSM. Antibodies against HPV were stable during the study period.

Vaccine Effectiveness Against 12-Month Incident and Persistent Anal Human Papillomavirus Infection Among Gay, Bisexual, and Other Men Who Have Sex With Men

BACKGROUND

Real-world evidence of human papillomavirus (HPV) vaccine effectiveness (VE) against longitudinal outcomes is lacking among gay, bisexual, and other men who have sex with men (GBM). We compared 12-month incidence and persistence of anal HPV infection between vaccinated and unvaccinated GBM.

METHODS

We recruited GBM aged 16-30 years in Montreal, Toronto, and Vancouver, Canada, from 2017 to 2019. Participants were followed over a median of 12 months (interquartile range, 12-13 months). Participants self-reported HPV vaccination and self-collected anal specimens for HPV DNA testing. We calculated prevalence ratios (PR) for 12-month cumulative incidence and persistence with ≥1 quadrivalent vaccine type (HPV 6/11/16/18) between vaccinated (≥1 dose at baseline) and unvaccinated participants using a propensity score-weighted, modified Poisson regression.

RESULTS

Among 248 participants, 109 (44.0%) were vaccinated at baseline, of whom 62.6% received 3 doses. PRs for HPV 6/11/16/18 were 0.56 (95% confidence interval [CI], .24-1.31) for cumulative incidence and 0.53 (95% CI, .25-1.14) for persistence. PRs were 0.23 (95% CI, .05-1.03) and 0.08 (95% CI, .01-.59) for incidence and persistence, respectively, among participants who received their first dose at age ≤23 years and 0.15 (95% CI, .03-.68) and 0.12 (95% CI, .03-.54) among participants who were sexually active for ≤5 years before vaccination.

CONCLUSIONS

Findings support national recommendations for HPV vaccination at younger ages or soon after sexual debut.

Effectiveness and cost-effectiveness of human papillomavirus vaccination strategies among men who have sex with men in China: a modeling study

Introduction

The health and economic benefits of human papillomavirus (HPV) vaccination targeted at men who have sex with men (MSM) in developing settings have been rarely assessed. This study aimed to evaluate the effectiveness and cost-effectiveness of different HPV vaccination strategies among MSM in China.

Methods

A Markov model was developed to simulate HPV transmission dynamics among a total of 30.73 million MSM in China. The corresponding natural history included 6 states: susceptible, infected with low-risk subtypes, high-risk subtypes, anogenital warts and anal cancer, and deaths from anal cancer. MSM were divided into three age groups with cut-off points of 27 and 45 years. Alternative vaccination strategies were built by allocating bivalent, quadrivalent, nine-valent, or no vaccine to each of the groups. We generated the prevented infections and deaths by vaccination compared with baseline (no vaccination) and calculated incremental cost-effectiveness ratios (ICERs) to determine the optimal strategy.

Results

The model showed that in 10 years, at baseline, the existing cases of anogenital warts would reach 5,464,225 (IQR, 4,685,708-6,174,175); that of anal cancer would reach 1,922.95 (1,716.56-2,119.93), resulting in 940.55 (732.27-1,141.87) deaths. Under 50% vaccination coverage among one age group, the prevented cases of anogenital warts were maximized with quadrivalent vaccines allocated to MSM aged 27-45 years; that of anal cancer were maximized when offering nine-valent vaccines to the same group. Under 50% vaccination coverage among all groups, the lowest ICER (34,098.09 USD/QALY, 31,146.54-37,062.88) was reached when only quadrivalent vaccines were provided. Based on this strategy, when the annual vaccination rate increased by 30%, the ICER (33,521.75 USD/QALY, 31,040.73-36,013.92) would fall below three times China's per capita GDP. When the vaccine price decreased by 60%, the ICER was reduced to 7,344.44 USD/QALY (4,392.89-10,309.23), indicating good cost-effectiveness taking China's per capita GDP as a threshold.

Conclusions

HPV vaccination can effectively reduce the prevalence and mortality of related diseases among MSM in China, especially quadrivalent vaccines for anogenital warts and nine-valent vaccines for anal cancer. MSM aged 27-45 years were the optimal group for vaccination. Annual vaccination and appropriate adjustment of vaccine price are necessary to further improve the cost-effectiveness.

Predictors of Anal High-Risk HPV Infection Across Time in a Cohort of Young Adult Sexual Minority Men and Transgender Women in New York City, 2015-2020

Cisgender sexual minority men (SMM) and transgender women are disproportionately vulnerable to HPV-related anal cancer, but little is known about longitudinal predictors of high-risk human papillomavirus (hrHPV) infection in this population. As such, this analysis aims to identify factors associated with incident anal hrHPV infection in a diverse cohort of young SMM and transgender women. This study of HPV infection, nested within a larger cohort study, took place between October 2015 and January 2020. Participants completed a brief computer survey assessing HPV symptomatology, risk, and prevention alongside multi-site testing, in addition to biannual cohort study assessments. In the analytic sample of 137 participants, 31.6% tested positive for an anal hrHPV infection, with 27.0% and 29.9% testing positive for incident anal hrHPV infections at Visits 2 and 3, respectively. When adjusting for time between study visits, participants had significantly greater odds of incident anal hrHPV at Visit 2 if they had a concurrent HSV infection (AOR = 5.08 [1.43, 18.00]). At Visit 3, participants had significantly greater odds of incident anal hrHPV infection if they reported a greater number of sex partners in the previous month (AOR = 1.25 [1.03, 1.51]). Prevalence of cancer-causing HPV at baseline was high and many participants tested positive for additional types of anal hrHPV at subsequent visits. Risk for newly detected anal hrHPV infection was significantly associated with biological and behavioral factors. Our findings strongly indicate a need for programs to increase uptake of HPV vaccination and provide HPV-related health education for sexual and gender minorities.

Natural History of Anal Papillomavirus Infection in HIV-Negative Men Who Have Sex With Men Based on a Markov Model: A 5-Year Prospective Cohort Study

Objective

Men who have sex with men (MSM) are at increased risk for Human papillomavirus (HPV) infection compared to women and heterosexual men. We aimed to assess the incidence, clearance and duration of anal human papillomavirus (HPV) infection in HIV-negative MSM and the influencing factors in a 5-year prospective cohort study.

Methods

From April 2016 to April 2021, HIV-negative MSM were recruited and followed every 6 months in Urumqi, Xinjiang, China. Questionnaires and anal swabs were collected at baseline and every 6 months. We detected 37 anal HPV genotypes using the HPV Geno Array Diagnostic Kit Test. Incidence and clearance rates of anal HPV infection and the influencing factors were estimated using a two-state Markov model.

Results

A total of 585 MSM were included with a median age of 37 years [interquartile range (IQR): 31–43 years] and were followed for a median 2.8 years (IQR: 1.8–3.6 years). Incidence rates for any HPV and high-risk HPV (Hr-HPV) were 53.4 [95% confidence interval (CI): 49.1–58.0] and 39.0 (95% CI: 35.7–42.5)/1,000 person-months. Median duration of infection was 9.67 (95% CI: 8.67–10.86) and 8.51 (95% CI: 7.57–9.50) months, respectively. Clearance rates for any HPV and Hr-HPV were 50.9 (95% CI: 46.7–55.3) and 62.1 (95% CI: 56.8–66.7)/1,000 person-months, respectively. HPV16 and HPV6 had the highest incidence, lowest clearance rate and longest duration of infection among Hr-HPV and low-risk HPV (Lr-HPV) types, respectively. Receptive anal sex is a risk factor for any HPV [hazard ratio (HR) = 1.66, 95% CI: 1.16–2.38] and Hr-HPV infection (HR = 1.99, 95% CI:1.39–2.85). Recent anal sex without condom use was significantly associated with any HPV (HR = 1.80, 95% CI: 1.10–2.94) and Hr-HPV infection (HR = 2.60, 95% CI: 1.42–4.77). Age ≥35 years was significantly associated with Lr-HPV HPV infection only (HR = 1.40, 95% CI: 1.02–1.93). Both inserted and receptive anal sex (HR = 0.60, 95% CI: 0.40–0.89) and anal sex ≥2 times per week (HR = 0.61, 95% CI: 0.43–0.87) were associated with reduced Hr-HPV clearance. Six of the nine-valent vaccine types (HPV6, 11, 16, 18, 52 and 58) occurred most frequently, which indicates the need for high vaccination coverage in MSM.

Conclusions

In this cohort study, high incidence and low clearance of any HPV, Hr-HPV and individual HPV infections emphasize the importance of MSM vaccination. Modifiable behavioral factors such as condoms and drug use should be incorporated into HPV prevention strategies.

Human papillomavirus antibody levels following vaccination or natural infection among young men who have sex with men

BACKGROUND

Australia introduced a school-based gender-neutral human papillomavirus (HPV) vaccination program for schoolgirls and boys aged 12-13 years in 2013. We examined HPV type specific antibody levels in unvaccinated young men who have sex with men (MSM) with natural infection and compared these to levels in those vaccinated against HPV.

METHODS

Serum specimens at baseline were collected from MSM aged 16-20 years in the HYPER1 and HYPER2 studies, conducted between 2010-2013 and 2017-2019, respectively. Merck's 4-plex HPV competitive Luminex Immunoassay was used to quantify HPV6, 11, 16 and 18 specific antibodies. We compared antibody levels for each HPV genotype between unvaccinated men (HYPER1) and vaccinated men (HYPER2) using the Mann-Whitney U test.

RESULTS

There were 200 unvaccinated men and 127 vaccinated men included in the analysis. Median antibody levels among vaccinated men were significantly higher than levels among unvaccinated men for HPV6 (223 mMU/ml vs 48 mMU/ml, p<0.0001), HPV11 (163 mMU/ml vs 21 mMU/ml, p<0.0001), HPV16 (888 mMU/ml vs 72 mMU/ml, p<0.0001) and HPV18 (161 mMU/ml vs 20 mMU/ml, p<0.0001). The median time between antibody level measurement and last vaccine dose was 47.7 (IQR 40.4 to 54.1) months. Antibody levels did not change over time for up to 66 months for all four genotypes among vaccinated men.

CONCLUSION

Among young MSM vaccinated with the quadrivalent HPV vaccine, antibody levels for HPV 6, 11, 16 and 18 were significantly higher than those in unvaccinated MSM following natural infection. Antibody levels following vaccination appeared to remain stable over time.

Incidence and Clearance of Penile High-Risk Human Papillomavirus Infection and Their Determinants Among HIV-Negative Men Who Have Sex With Men

BACKGROUND

Men who have sex with men (MSM) are at increased risk of anogenital human papillomavirus (HPV) infections. We aimed to assess the incidence and clearance of penile high-risk HPV (hrHPV) infections and their determinants among HIV-negative MSM living in the Netherlands.

METHODS

Between 2010 and 2015, HIV-negative MSM were semiannually tested for penile HPV and completed detailed questionnaires on health and sexual behavior. Self-collected penile swabs were tested for HPV DNA using SPF10-PCR DEIA/LiPA25 system. Type-specific hrHPV incidence (IR) and clearance rates (CR) were calculated for 12 hrHPV types (HPV-16, HPV-18, HPV-31, HPV-33, HPV-35, HPV-39, HPV-45, HPV-51, HPV-52, HPV-56, HPV-58, and HPV-59). Determinants of incidence and clearance of HPV-16 and HPV-18, separately, and combined 7 hrHPV types covered by the nonavalent vaccine were assessed by Poisson regression using generalized estimating equations for combined hrHPV types.

RESULTS

We included 638 HIV-negative MSM, with a median age of 38 (interquartile range, 33-43) years. HPV-16 had an IR of 4.9/1000 person-months of observation at risk (PMO; 95% confidence interval [95% CI], 3.8-6.3) and CR of 90.6/1000 PMO (95% CI, 60.7-135.1). The IR and CR of HPV-18 were 3.4/1000 PMO (95% CI, 2.5-4.5) and 119.2/1000 PMO (95% CI, 76.9-184.8), respectively. Age and condom use during insertive anal sex were not associated with hrHPV incidence, whereas high number of recent sex partners was.

CONCLUSIONS

The relatively high IR and low CR of penile HPV-16 and HPV-18 among HIV-negative MSM correlates with their high prevalence and oncogenic potential. Incident HPV infections were associated with recent sexual risk behavior.

Incidence, Clearance, and Persistence of Anal Human Papillomavirus in Men Who Have Sex With Men Living With Human Immunodeficiency Virus: Implications for Human Papillomavirus Vaccination

BACKGROUND

Men who have sex with men living with human immunodeficiency virus have a high risk of anal cancer. We estimate the likely benefit of human papillomavirus (HPV) vaccination among participants of the Anal Cancer Examination study.

METHODS

Anal swabs were collected for the detection and genotyping of anal HPV DNA by linear array (Roche Diagnostics) in this 2-year multicenter prospective cohort. We calculated the proportion of men, stratified by age, without detectable vaccine type-specific DNA.

RESULTS

Overall, 255 men, with a median age of 50 years (interquartile range, 44-56 years) contributed 488.9 person-years of follow-up. After 2 years of follow-up, 149 (58%; 95% confidence interval [CI], 52-65) had at least 1 high-risk HPV (HRHPV), and 71 (28%, 95% CI, 22-34) had HPV types 16/18 detected. Assuming that DNA-negative men would receive vaccine protection, vaccination at baseline could potentially prevent HRHPV infection in 10.2% of men (95% CI, 6.8-14.6, 26 of 255) 2 years later from incident HRHPV covered by the bivalent and quadrivalent vaccine, and 29.4% of men (95% CI, 23.9-35.4, 75/255) from incident HRHPV covered by the nonavalent vaccine.

CONCLUSION

Though there is high prevalence of anal HPV in men who have sex with men living with human immunodeficiency virus, there was also a high incidence of HRHPV vaccine types in the 2-year follow-up, indicating potential for prevention if these men were not previously infected with HPV vaccine types and were vaccinated at their baseline visit.

Estimating incidence rates of grouped HPV types: A systematic review and comparison of the impact of different epidemiological assumptions

BACKGROUND

Some studies on human papillomavirus (HPV) provide not only type-specific incidence rates (IR), but also IRs of HPV groupings (e.g. the nonavalent grouping). We made an inventory of the different approaches used to calculate such IRs and assessed their impact on the estimated IRs of HPV groupings.

METHODS

We performed a systematic review assessing all approaches used in literature to estimate IRs. Subsequently we applied these approaches to data of a Dutch cohort study on HPV in men who have sex with men (H2M). IRs were estimated for six different HPV groupings.

RESULTS

The systematic review yielded six different approaches (A-F) for estimating the IRs, varying in exclusion criteria at baseline, and the definitions of an incident event and person-time. Applying these approaches to the H2M dataset (n = 749), we found differences in the number of participants at risk, number of incidents events, person-time, and IR. For example, for the nonavalent grouping, depending on the approach chosen, the IR varied between 3.09 and 6.54 per 100 person-months.

CONCLUSION

In published studies different epidemiological assumptions are used to estimate IRs of grouped HPV types, leading to widely differing estimates of IRs. IRs between different studies may therefore not be comparable.

Monitoring human papillomavirus prevalence among young Australian women undergoing routine chlamydia screening

INTRODUCTION

Australia has recently implemented major changes in cervical cancer prevention policies including introduction of primary human papillomavirus (HPV) screening starting at age 25, and replacement of the quadrivalent HPV vaccine with the nonavalent vaccine in the national school-based program. We assessed the feasibility and utility of conducting HPV testing in residual clinical specimens submitted for routine Chlamydia trachomatis screening, as a means of tracking HPV vaccine program impact among young sexually active women.

METHODS

De-identified residual specimens from women aged 16-24 years submitted for chlamydia testing were collected from three pathology laboratories in Victoria and New South Wales. Limited demographic information, and chlamydia test results were also collected. Patient identifiers were sent directly from the laboratories to the National HPV Vaccination Program Register, to obtain HPV vaccination histories. Samples underwent HPV genotyping using Seegene Anyplex II HPV 28 assay.

RESULTS

Between April and July 2018, 362 residual samples were collected, the majority (60.2%) of which were cervical swabs. Demographic data and vaccination histories were received for 357 (98.6%) women (mean age 21.8, SD 2.0). Overall, 65.6% of women were fully vaccinated, 9.8% partially, and 24.7% unvaccinated. The majority (86.0%) resided in a major city, 35.9% were classified in the upper quintile of socioeconomic advantage and chlamydia positivity was 7.8%.The prevalence of quadrivalent vaccine-targeted types (HPV6/11/16/18) was 2.8% (1.5-5.1%) overall with no differences by vaccination status (p = 0.729). The prevalence of additional nonavalent vaccine-targeted types (HPV31/33/45/52/58) was 19.3% (15.6-23.8%). One or more oncogenic HPV types were detected in 46.8% (95% CI 41.6-52.0%) of women.

CONCLUSIONS

HPV testing of residual chlamydia specimens provides a simple, feasible method for monitoring circulating genotypes. Applied on a larger scale this method can be utilised to obtain a timely assessment of nonavalent vaccine impact among young women not yet eligible for cervical screening.

Prevalence of human papillomavirus in teenage heterosexual males following the implementation of female and male school-based vaccination in Australia: 2014-2017

BACKGROUND

Australia introduced a school-based human papillomavirus (HPV) vaccination program for females aged 12-13 years in 2007, with a three-year catch-up to age 26; and for boys aged 12-13 from 2013, with a two-year catch-up to age 15. This study aimed to compare the prevalence of penile HPV between teenage heterosexual males in cohorts eligible or non-eligible for the school-based male vaccination program.

METHODS

Between 2014 and 2017, sexually active heterosexual males aged 17-19 were recruited from sexual health centres and community sources across Australia. Males provided a self-collected penile swab for 37 HPV genotypes using Roche Linear Array and completed a questionnaire. We calculated adjusted prevalence ratios (aPR) of HPV between males in two periods: 2014-2015 (preceding implementation of school-based male vaccination) and 2016-2017 (eligible for school-based male vaccination). Self-reported vaccine doses were confirmed with doses reported to the National HPV Vaccination Program Register.

RESULTS

Overall, 152 males were recruited in 2014-2015 and 146 in 2016-2017. Numbers of female sex partners and condom use did not differ between the two periods. The prevalence of quadrivalent vaccine-preventable [4vHPV] genotypes (6/11/16/18) was low in both periods (2.6% [2014-15] versus 0.7% [2016-17]; p = 0.371; aPR 0.28 [95% CI: 0.03-2.62]). Compared with men in 2014-2015, men in 2016-2017 had a lower prevalence of any of the 37 HPV genotypes tested (21.7% versus 11.6%; aPR 0.62 [95% CI: 0.36-1.07]) and any of the 13 high-risk genotypes tested (15.8% versus 7.5%; aPR 0.59 [95% CI: 0.30-1.19]). Prevalence of low-risk HPV genotypes did not differ between the two periods. Of the males recruited in 2016-2017, 55% had received ≥1 vaccine dose.

CONCLUSION

The prevalence of 4vHPV genotypes among teenage heterosexual males in both cohorts was low, presumably due to herd protection from the female-only vaccination program. Further studies are required to determine the impact of universal HPV vaccination on HPV prevalence in males.

2020, sexually transmissible infections and HIV in gay, bisexual and other men who have sex with men

This editorial accompanies a series of papers dealing with this watershed period for HIV and sexually transmissible infections (STI) infections in gay, bisexual and other men who have sex with men (GBM). We are delighted to share with you the views of some international opinion leaders on what the future may hold and what challenges lie ahead. In this issue of the Journal, authors describe current HIV and STI incidence among GBM and predict the future.

Human papillomavirus vaccination in men who have sex with men - what will be required by 2020 for the same dramatic changes seen in heterosexuals

This paper addresses the issue of whether men who have sex with men (MSM) will share the spectacular reductions in human papillomavirus (HPV) infection and its associated neoplasia that we are currently witnessing in heterosexuals. The reproductive rate for HPV infection in heterosexuals is not well established, but 70% vaccination coverage in women has resulted in a fall of more than 90% in genital warts and HPV types 16/18 in young women and 80% fall in young men indicating that the critical vaccination threshold has been exceeded for this group. Published data on the three elements of the reproductive rate for HPV infection (i.e. transmission probability per sexual partnership, rate of partner change and duration of infectiousness) suggest they are higher in MSM than heterosexuals. This indicates that the reproductive rate for HPV will be higher in MSM and hence the critical vaccination threshold will also be higher. But while vaccinating 70% of girls protect 70% of sexual partnerships in heterosexuals, vaccinating 70% of boys protect more than 70% of partnerships in MSM. Only 9% (30% by 30%) of sexual partnerships in MSM are not protected with 70% coverage. Therefore vaccinating 70% of boys will protect 91% of sexual partnerships in MSM. However the efficacy of the HPV vaccine is much lower when sexually active MSM are vaccinated rather than boys. We argue that if MSM are to have the same benefit from the HPV vaccine that heterosexuals had, boys and not adult MSM will need to be vaccinated.

Are Boys Ready for Human Papillomavirus Vaccine? A National Study of Boys in Malaysia

BACKGROUND

The aim of this study was to investigate factors associated with the willingness of boys to accept the human papillomavirus (HPV) vaccine.

METHODS

A nationwide cross-sectional survey among Secondary One male students in Malaysia.

RESULTS

Among 2823 respondents, knowledge about HPV infection and the HPV vaccine was extremely poor. The mean total knowledge score was only 3.17 (SD ± 2.14), out of a possible score of 10. The majority of respondents were unaware that vaccinating boys can help protect girls against HPV infection (81.6%), and HPV is a sexually transmitted infection (70.1%). Many had the misconception that only females get HPV (78.9%). In multivariable analysis, the factors associated with the intention to receive the HPV vaccination were: agreeing boys need to be vaccinated against HPV infection (odds ratio [OR], 2.05; 95% confidence interval [CI], 1.57-2.68), perceiving their parents might allow them to get the HPV vaccine (OR, 1.66; 95% CI, 1.18-2.34), perceived susceptibility to HPV infection (OR, 1.63; 95% CI, 1.06-2.52), and attending a rural school (OR, 1.49; 95% CI, 1.14-1.95).

CONCLUSIONS

Public health educational programs that are focused and tailored on parents consenting to HPV vaccination for boys at a young age can be useful in improving HPV vaccination rates among boys. There is also a pressing need to educate boys about the benefits of HPV vaccination in males and about HPV disease susceptibility to facilitate adoption of the HPV vaccine by young adults in the future.

Modeling HPV vaccination scale-up among urban young men who have sex with men in the context of HIV

INTRODUCTION

Young men who have sex with men (YMSM) are at high risk to contract human papillomavirus (HPV). While an effective vaccination exists, its use among YMSM is markedly lower compared to non-MSM and women. This study compares scaling up HPV vaccination in conjunction with other prevention strategies.

METHODS

An agent-based model of urban YMSM (≤26 years of age) reflective of the demography of Philadelphia, PA, simulated for up to ten years of follow-up to examine anal and oral transmission of the HPV genotypes covered in the nonavalent (9v) vaccine: 6, 11, 16, 18, 31, 33, 45, 52, 58. Starting HPV prevalences ranged from a high of 18% (type 6) to a low of 6% (type 31); overall 65% of individuals carried any HPV genotype. Simulated levels of vaccination were ranged from 0% to 13% (present-day level), 25%, 50%, 80% (Healthy People 2020 target), and 100% in conjunction with condom use and HIV seroadaptive practices. The primary outcome was the relative reduction in HPV infection.

RESULTS

Compared to present-day vaccination levels (13%), scaling-up vaccination led to expected declines in 10-year post-simulation HPV prevalence. Anal HPV (any 9v types) declined by 9%, 27%, 46%, and 58% at vaccination levels of 25%, 50%, 80%, and 100%, respectively. Similarly, oral HPV (any 9v types) declined by 11%, 33%, 57%, and 71% across the same levels of vaccine uptake. Comparing the prevention strategies, condoms blocked the greatest number of anal transmissions when vaccination was at or below present-day levels. For oral transmission, vaccination was superior to condom use at all levels of coverage.

CONCLUSIONS

Public health HPV preventions strategies should continue to emphasize the complementary roles of condoms and vaccination, especially for preventing oral infection. Improving vaccination coverage will ultimately have the greatest impact on reducing HPV infection among YMSM.

Potential effectiveness of prophylactic HPV immunization for men who have sex with men in the Netherlands: A multi-model approach

BACKGROUND

Men who have sex with men (MSM) are at high risk for anal cancer, primarily related to human papillomavirus genotype 16 (HPV16) infections. At 8.5 per 100,000 per year, the incidence rate of anal cancer among MSM is similar to that of cervical cancer among adult women in the Netherlands. However, MSM are not included in most HPV vaccination programs. We explored the potential effectiveness of prophylactic immunization in reducing anogenital HPV16 transmission among MSM in the Netherlands.

METHODS AND FINDINGS

We developed a range of mathematical models for penile-anal HPV16 transmission, varying in sexual contact structure and natural history of infection, to provide robust and plausible predictions about the effectiveness of targeted vaccination. Models were informed by an observational cohort study among MSM in Amsterdam, 2010-2013. Parameters on sexual behavior and HPV16 infections were obtained by fitting the models to data from 461 HIV-negative study participants, considered representative of the local MSM population. We assumed 85% efficacy of vaccination against future HPV16 infections as reported for HIV-negative MSM, and age-specific uptake rates similar to those for hepatitis B vaccination among MSM in the Netherlands. Targeted vaccination was contrasted with vaccination of 12-year-old boys at 40% uptake in base-case scenarios, and we also considered the effectiveness of a combined strategy. Offering vaccine to MSM without age restrictions resulted in a model-averaged 27.3% reduction (90% prediction interval [PI] 11.9%-37.5%) in prevalence of anal HPV16 infections, assuming similar uptake among MSM as achieved for hepatitis B vaccination. The predicted reduction improved to 46.1% (90% PI 21.8%-62.4%) if uptake rates among MSM were doubled. The reductions in HPV16 infection prevalence were mostly achieved within 30 years of a targeted immunization campaign, during which they exceeded those induced by vaccinating 40% of preadolescent boys, if started simultaneously. The reduction in anal HPV16 prevalence amounted to 74.8% (90% PI 59.8%-93.0%) under a combined vaccination strategy. HPV16 prevalence reductions mostly exceeded vaccine coverage projections among MSM, illustrating the efficiency of prophylactic immunization even when the HPV vaccine is given after sexual debut. Mode of protection was identified as the key limitation to potential effectiveness of targeted vaccination, as the projected reductions were strongly reduced if we assumed no protection against future infections in recipients with prevalent infection or infection-derived immunity at the time of immunization. Unverified limitations of our study include the sparsity of data to inform the models, the omission of oral sex in transmission to the penile or anal site, and the restriction that our modeling results apply primarily to HIV-negative MSM.

CONCLUSIONS

Our findings suggest that targeted vaccination may generate considerable reductions in anogenital HPV16 infections among MSM, and has the potential to accelerate anal cancer prevention, especially when combined with sex-neutral vaccination in preadolescence.

Age-Specific Pattern of Anogenital Wart in Men Who Have Sex With Men

We examined the proportion of anogenital warts in men who have sex with men attending a sexual health center. Anal warts were most common in younger men who have sex with men (5.8% for age <21 years) and became less common with age (2.8% in age >50 years), but penile warts occurred at approximately the same proportion (~1.5%) over all age groups.

Prevalence of Anal Squamous Intraepithelial Lesions in HIV-1-Infected Young Men Who Have Sex With Men and Transwomen

OBJECTIVE

Anal cancer rates are increasing among HIV-infected persons. Although an efficacious human papillomavirus (HPV) vaccine is available, HPV vaccination rates remain low. Therefore, providers perform anal cancer screening, but there is no consensus on the optimal methods or timing of screening. This study was performed to determine the prevalence of and factors associated with anal squamous intraepithelial lesions in sexually active HIV-infected young men who have sex with men and transgender women.

MATERIALS AND METHODS

We performed a single-center, retrospective study of sexually active HIV-infected young men who have sex with men and transgender women aged 13 to 24 years at an HIV clinic in Atlanta GA from 2009 to 2016. We used analysis of variance and χ tests of independence to evaluate bivariate associations and identify demographic, behavioral, and clinical risk factors.

RESULTS

Of 314 subjects with a mean (SD) age of 20.4 (2.1) years at initial anal cytology testing, 5% had completed the HPV vaccine series at or before the time that cytology was obtained. Ninety-five percent of the anal cytology tests obtained were abnormal, and 72 (29%) of those subjects returned for diagnostic testing either by intraoperative biopsy or high-resolution anoscopy. Fifty-seven percent of those who underwent biopsy had histologic high-grade squamous intraepithelial lesions including 2 cases of carcinoma in situ. A history of greater than 20 lifetime sexual partners was associated with abnormal histology (probability < 0.001, p = .017).

CONCLUSIONS

Our study highlights the value of early, standardized screening to avoid missing anal dysplasia or cancer, particularly in unvaccinated persons with high numbers of sexual partners.

Vaccine-preventable anal infections by human papillomavirus among HIV-infected men who have sex with men

AIM

HIV-infected men who have sex with men (MSM) show the highest prevalence of anal HPV infection. Anal prevalence of the HPVs targeted by the quadrivalent HPV vaccine (4vHPV) and nonavalent HPV vaccine (9vHPV) was estimated in this population.

MATERIALS & METHODS

Anal specimens were collected from HIV-infected MSM attending a sexually transmitted infection/HIV center. Specimens were analyzed using the Linear Array HPV Genotyping Test.

RESULTS

A total of 49.5 and 71.2% of the 313 enrolled MSM harbored at least one of the 4vHPV and 9vHPV types, respectively. A significantly decreasing trend was observed for the prevalence of both 4vHPV (p = 0.04) and 9vHPV types (p < 0.001) across age classes.

CONCLUSION

A substantial proportion of HIV-infected MSM do not harbor a current anal infection with vaccine-preventable HPVs. The potential benefit of the 4vHPV versus 9vHPV vaccination in these subjects, including older MSM, should be investigated.

Epidemiology of Any and Vaccine-Type Anogenital Human Papillomavirus Among 13-26-Year-Old Young Men After HPV Vaccine Introduction

PURPOSE

The aims of this study were to determine prevalence of and factors associated with any human papillomavirus (HPV) and vaccine-type HPV among young men after vaccine introduction, stratified by vaccination status.

METHODS

Young men were recruited from clinical sites from 2013 to 2015, completed a survey, and were tested for 36 anogenital HPV types. We determined factors associated with ≥1 HPV type among all participants, and vaccine-type HPV (HPV6, 11, 16, and/or 18) among all, vaccinated and unvaccinated participants, using multivariable regression.

RESULTS

Mean age was 21.5 years and 26% had received at least one HPV vaccine dose. HPV prevalence was lower in vaccinated versus unvaccinated young men (50.5% vs. 62.6%, p = .03). HPV positivity was discordant by anogenital site. At both sites, 59.4% were positive for ≥1 HPV type and 26.0% for ≥1 4-valent vaccine type. In multivariable logistic regression, factors associated with ≥1 HPV type among all participants were frequency of oral sex (odds ratio [OR] = 1.80, 95% confidence interval [CI] = 1.00-3.24), recent smoking (OR = 1.84, CI = 1.17-2.90), and sexually transmitted infection history (OR = 1.56, CI = 1.02-2.38). Factors associated with vaccine-type HPV among all participants were white versus black race (OR = 1.91, CI = 1.10-3.34) and gonorrhea history (OR = 2.52, CI = 1.45-4.38); among vaccinated participants were private versus Medicaid insurance (OR = 5.6, CI = 1.46-20.4) and private versus no insurance (OR = 15.9, CI = 3.06-83.3); and among unvaccinated participants was gonorrhea history (OR = 1.83, CI = 1.03-3.24).

CONCLUSIONS

Anogenital HPV prevalence was high and vaccination rates low among young men 2-4 years after vaccine introduction, underscoring the urgency of increasing vaccination rates and vaccinating according to national guidelines.

The epidemiology of oral human papillomavirus infection in healthy populations: A systematic review and meta-analysis

Human papillomavirus (HPV) is a potentially oncogenic sexually transmitted infection. As the incidence of oropharyngeal cancer (OPC) caused by oral HPV infections is rising, further investigation into the natural history of such infections is needed. This systematic review and meta-analysis aimed to synthesize data on the prevalence, incidence, clearance, and persistence of oral HPV infections in healthy individuals. A systematic review of literature published between January 1995 and August 2017 was conducted using Ovid MEDLINE, PubMed, Embase, and the Cochrane Library. Meta-analysis of prevalence and incidence data was conducted. Clearance and persistence data were extracted. Sixty-six studies met the inclusion criteria. Meta-analysis demonstrated an overall prevalence of 7.7% for all types of HPV and 1.4% for high-risk HPV16. The overall incidence was 4.38 cases per 1000 person-months for all HPV types and 0.92 cases per 1000 person-months for HPV16. This systematic review and meta-analysis demonstrated that oral HPV infection has a lower prevalence and incidence than cervicogenital HPV infection in healthy individuals. Nonetheless, oral HPV is still an important concern, given its oncogenicity and the rising incidence of oropharyngeal cancer. Consistency of methodology will allow for better future comparisons, particularly of infection clearance and persistence.

Using Facebook to Recruit Young Australian Men Into a Cross-Sectional Human Papillomavirus Study

Background

Young men can be difficult to engage in health research using traditional methods of recruitment. Social networking sites are increasingly being used to recruit participants into health research, due to their cost effectiveness, overall generalizability, and wide reach.

Objective

The aim of this study was to determine the feasibility of using Facebook to recruit young Australian men into a human papillomavirus (HPV) prevalence study.

Methods

We recruited male permanent residents of Australia, aged 18 to 35 years, into the HPV in Young Males (HYM) study through targeted advertising placed on Facebook. Consenting participants completed an online questionnaire and provided a self-collected penile swab for HPV DNA detection and genotyping. We compared sociodemographic characteristics of the study population with those of the general Australian male population, based on Australian 2011 census data.

Results

Between February 2015 and February 2017, targeted Facebook advertisements reached 1,523,239 men, resulting in 41,811 clicks through to the study website, with 1072 (2.56%) converting to lodgment of an expression of interest. Of these, 681 (63.53%) provided written informed consent and 535 (78.6% of recruited participants) completed all the study requirements. Reasons for participating in the study included altruism, past history of HPV, gaining more knowledge about HPV or the vaccine, working in the health industry, and the monetary compensation. The average advertising cost per completed study participant was Aus $48. Compared with the census population, HYM study participants were more likely to be Australian born (P<.001), be from Victoria (P=.003) or the Australian Capital Territory (P=.004), reside in a major city (P<.001), and have completed undergraduate (P<.001) or postgraduate education (P<.001). HYM study participants were less likely to report being a current smoker (P=.03), but were more likely to identify as bisexual or homosexual (294/529, 55.6%, P<.001), than the general population.

Conclusions

Using Facebook is a feasible and efficient strategy for the recruitment of men from across Australia for HPV testing. This method could be used for monitoring the impact of HPV vaccination. Additional targeting may achieve a sample that is broadly demographically representative of the Australian population. Future research should explore how the sexual risk behavior characteristics of populations recruited through Facebook compare with those of traditional recruitment methods.

A multicentre double-blind randomised controlled trial evaluating the efficacy of daily use of antibacterial mouthwash against oropharyngeal gonorrhoea among men who have sex with men: the OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA) study protocol

BACKGROUND

Gonorrhoea is one of the most common sexually transmissible infections in men who have sex with men (MSM). Gonorrhoea rates have increased substantially in recent years. There is concern that increasing gonorrhoea prevalence will increase the likelihood of worsening antibiotic resistance in Neisseria gonorrhoeae. A recent randomised controlled trial (RCT) demonstrated that a single-dose of mouthwash has an inhibitory effect against oropharyngeal gonorrhoea. We are conducting the first RCT to evaluate whether daily use of mouthwash could reduce the risk of acquiring oropharyngeal gonorrhoea.

METHODS/DESIGN

The OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA) study is a double-blind RCT and will be conducted at several sexual health clinics and high caseload General Practice (GP) clinics in Melbourne and Sydney, Australia. A total of 504 MSM attending the participating sites will be recruited. Participants will be randomised to either using 'Study mouthwash A' or 'Study mouthwash B' for 12 weeks. Study mouthwash A was inhibitory against N. gonorrhoeae in vitro, whereas study mouthwash B was not. Participants will be instructed to rinse and gargle the study mouthwash for 60 seconds every day. The primary outcome is the proportion of participants with oropharyngeal gonorrhoea detected by nucleic acid amplification test by 12 weeks.

DISCUSSION

The results from this trial may provide a novel way to reduce gonorrhoea prevalence and transmission without the use of antibiotics that may be associated with development of resistance. If shown to be effective, the widespread use of mouthwash will reduce the prevalence of oropharyngeal gonorrhoea, which plays key role in driving the emergence of gonococcal antimicrobial resistance through DNA exchange with oral commensal bacteria. The anticipated net effect will be interruption of onward transmission of N. gonorrhoeae within high density sexual networks within MSM populations.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12616000247471 , registered on 23rd February 2016.

Human Papillomavirus Positivity in the Anal Canal in HIV-Infected and HIV-Uninfected Men Who Have Anal Sex with Men in Guangzhou, China: Implication for Anal Exams and Early Vaccination

Background. The epidemiology of HPV in men who have sex with men (MSM) in Guangzhou, China, had not been reported previously. Methods. HIV-infected and HIV-uninfected MSM were recruited from a Guangzhou-based MSM clinic in 2013. Sociodemographic characteristics and sexual behaviors were collected. An anal cytological sample was taken for HPV testing. Results. We recruited 79 HIV-infected and 85 HIV-uninfected MSM. The median age was 26 years in both groups. The positivities of anal HPV of any type (81.0% versus 48.2%), any high risk type (50.6% versus 27.1%), any low risk type (55.7% versus 31.8%), and any 9-valent vaccine type (74.7% versus 36.5%) were all significantly higher among HIV-infected compared to that among HIV-negative MSM (p for all < 0.05). The great majority of HPV-infected MSM were infected with 9-valent vaccine types (59 out of 64 HIV-infected and 31 out of 41 HIV-uninfected). Anal bacterial infections were associated with higher anal HPV positivity and greater number of anal HPV types. Conclusion. Sexually active MSM in Guangzhou, especially those infected with HIV, had high and multiple HPV detections. The majority of these cases were potentially preventable by HPV vaccine. Regular anal exams and early HPV vaccination are warranted in this population.

Anal human papillomavirus infection: prevalence, diagnosis and treatment of related lesions

Human papillomavirus (HPV) infection is mostly asymptomatic, but may also have many diverse clinical signs encompassing benign ano-genital lesions, and carcinomas. Recently, interest has also particularly focused on anal cancer since, over the last decades, its incidence has been greatly increasing in developed countries, both in women and men and is drastically higher in specific risk groups, such as men who have sex with men (MSM) and HIV-1 infected individuals. Approximately 88% of anal cancer cases worldwide are associated with HPV infection. This review summarizes our current understanding of anal HPV infection, discussing its epidemiology and risk factors in various populations, and the state of the art in the detection of anal HPV infection and its related lesions through both cytology and histology. Finally, we discuss the clinical management and therapy for these lesions.

Human papillomavirus prevalence and associated factors in women and men in south China: a population-based study

Oncogenic human papillomavirus (HPV) infection is a cause of many anogenital cancers in women and men; however, there is little research on HPV prevalence and risk factors that includes both women and men from the same population. A total of 4687 participants, including 2378 women and 2309 men aged 18–55 years old from the same community, were enrolled in the study in Liuzhou, China. Exfoliated cells were collected from the participants from different anatomic sites and were tested for 13 oncogenic and 3 non-oncogenic HPV types. The prevalence of any oncogenic HPV type was higher in women than in men (18.7% vs 9.4%, P<0.001), whereas the prevalence of HPV 6 and 11 infection was similar (1.4% vs 1.2%, P=0.6832). HPV 52, 58, 16, 39 and 18 were the five most prevalent types in both sexes. Sexual and hygienic behaviors were associated with HPV infection in both women and men. We found that oncogenic HPV DNA detection is more prevalent in women than in men in China, whereas the prevalence of HPV 6 and 11 is similar in both sexes. The data indicate that the interaction of host and virus might be different among high- and low-risk HPV types.

Anal human papillomavirus in HIV-uninfected men who have sex with men: incidence and clearance rates, duration of infection, and risk factors

Little is known regarding the natural history of anal human papillomavirus (HPV) infection. We aimed to evaluate incidence and clearance rates, their risk factors, and duration of anal HPV infection in HIV-uninfected men who have sex with men (MSM). A longitudinal study was conducted. Anal samples were analysed using the Linear Array HPV Genotyping test. Incidence and clearance rates, and corresponding risk factors, were estimated using a two-state Markov model. Overall, 155 MSM (median age 33.4 years) attending the largest sexually transmitted infection (STI) centre in Rome, Italy, were followed for a median of 12.2 months (Q1-Q3: 7.0-18.1). Incidence and clearance rates for any HPV were 85.6 (95% CI: 58.4-125.4) and 35.6 (95% CI: 24.7-51.5) × 1000 person-months, respectively; the median duration of infection was 9.4 months (Q1-Q3: 7.5-12.1). Receptive anal sex emerged as the only risk factor for the acquisition of any HPV (Hazard Ratio, HR = 2.65, 95% CI: 1.16-6.06). The incidence rates for carcinogenic and non-carcinogenic types were 42.3 (95% CI: 29.2-61.4) and 29.2 (95% CI: 19.5-43.7) × 1000 person-months, respectively (p = 0.13); their clearance rates were 62.9 (95% CI: 45.1-87.7) and 65.7 (95% CI: 47.4-91.0) × 1000 person-months, respectively (p = 0.83). HPV16 showed the lowest clearance rate among carcinogenic types (59.7 × 1000 person-months), and a duration of infection of 16.8 months. In conclusion, a higher incidence rate was observed for carcinogenic compared to non-carcinogenic HPV types, although the difference was not significant. HPV16 emerged as the type with the longest duration of infection and the lowest clearance rate among carcinogenic types.

Antibody responses following incident anal and penile infection with human papillomavirus in teenage men who have sex with men

Men who have sex with men (MSM) are at risk for human papillomavirus (HPV)-related anal cancer. Few data exist on antibody responses following incident anogenital infection with HPV in teenage MSM. A cohort of 200 MSM aged 16-20 years from Melbourne, Australia were assessed at baseline, 3, 6 and 12 months. At each visit anal and penile swabs were collected for HPV DNA and serum for HPV antibodies for genotypes 6, 11, 16 and 18 (Merck's Multiplex Assays using Luminex). The main outcome, seroconversion, was defined as the detection of HPV antibodies following a negative antibody result for the same HPV type at baseline. The seroincidence rates for HPV types 6, 11, 16 and 18 were: 19 (95% CI 12-26), 7 (3-12), 4 (1-8) and 6 (3-11) per 100 person-years, respectively. Men who experienced incident anal HPV infections from types 6/11 were significantly more likely to develop serum antibodies to the same HPV type(s) than those who experienced incident anal infections from types 16/18 [73 vs. 18%, odds ratio (OR) = 15, 95% CI: 2-118]. The median time between incident anal HPV infection and seroconversion for HPV 6, 11, 16 and 18 was: 91, 38, 161 and 182 days, respectively. Antibody responses against HPV types 6/11 were significantly more likely to occur following incident anal compared with incident penile infection with HPV types 6/11 (OR = 6, 95% CI: 2-21). The likelihood of antibody responses following anogenital HPV infections depends on the HPV type and site of infection.

Incidence, Duration, Persistence, and Factors Associated With High-risk Anal Human Papillomavirus Persistence Among HIV-negative Men Who Have Sex With Men: A Multinational Study

BACKGROUND

Given high rates of anal disease, we investigated the natural history of high-risk anal human papillomavirus (HPV) among a multinational group of men who have sex with men (MSM) aged 18-64 years.

METHODS

Anal specimens from human immunodeficiency virus-negative men from Brazil, Mexico, and the United States were genotyped. Over 2 years, 406 MSM provided evaluable specimens every 6 months for ≥2 visits. These men were stratified into men who have sex only with men (MSOM, n = 70) and men who have sex with women and men (MSWM, n = 336). Persistence was defined as ≥12 months' type-specific duration and could begin with either a prevalent or incident infection. Prevalence ratios and 95% confidence intervals were calculated by Poisson regression.

RESULTS

Median follow-up time was 2.1 years. Retention was 82%. Annual cumulative incidence of 9-valent vaccine types was 19% and 8% among MSOM and MSWM, respectively (log-rank P = .02). Duration of anal HPV did not differ for MSOM and MSWM and was a median of 6.9 months for HPV-16 after combining men from the 2 groups. Among men with prevalent high-risk infection (n = 106), a total of 36.8%, retained the infection for at least 24 months. For those with prevalent HPV-16 (n = 27), 29.6% were persistent for at least 24 months. Persistence of high-risk HPV was associated with number of male anal sex partners and inversely associated with number of female sex partners.

CONCLUSIONS

MSM with prevalent high-risk HPV infection should be considered at increased risk for nontransient infection.

HPV-associated head and neck cancers in the Asia Pacific: A critical literature review & meta-analysis

BACKGROUND

Malignancies of the upper aero-digestive tract are a major public health problem, especially in the Asia Pacific. Certain Human papillomaviruses (HPVs) are well-established risk factors for carcinoma of the uterine cervix and for a subset of head and neck carcinomata: however their true importance in different populations and anatomical subsites remains unclear. The major risk factors in Asia Pacific remain smoked/smokeless tobacco, areca nut, alcohol abuse and poor diet, with limited evidence for HPVs. We review published studies of association of HPV with anatomical site-specific Head & Neck Squamous Cell Carcinoma (HNSCC) in these populations and attempt a meta-analysis.

MATERIALS AND METHODS

From MEDLINE/PubMed/WEB-of SCIENCE/EMBASE/Scopus databases we found 67 relevant studies with a total of 7280 cases: 15 case-control studies met our inclusion criteria for meta-analysis, totaling 1106 cases & 638 controls. HPV detection rates, sample site and size, and methods of tissue preservation and HPV detection were tabulated for each study.

RESULTS

Studies were heterogeneous in terms of sample selection and method of detection of HPVs. Most were of limited quality. Averaging data from 67 studies of HNSCC, the prevalence of HPV of any subtype is approximately 36%. PCR (polymerase chain reaction) was the most used detection method and HPV16 the most common genotype reported. Meta-analyses of case-control studies from this region reveal significant heterogeneity but suggest higher HPV prevalence in oropharyngeal cancer (OR: 14.66; 95%CI: 6.09-35.26) compared to oral cavity cancer and laryngeal cancer; (OR: 4.06; 95%CI: 3.05-5.39 & OR: 3.23; 95%CI: 1.37-7.61) respectively.

CONCLUSION

In view of the significant association of HPV with HNSCC, studies with accurate subsite classification and more sensitive detection methods are necessary. Accurate data from this geographical region are essential to inform public health policies and treatment decisions, especially as studies from Europe and North America reveal HPV-driven cancers to be less aggressive, permitting treatment de-intensification.

Awareness and acceptance of human papillomavirus (HPV) vaccination among males attending a major sexual health clinic in Wuxi, China: A cross-sectional study

OBJECTIVE

To study the awareness and acceptance of human papillomavirus (HPV) vaccination among sexually active men having sex with men (MSM) and men not having sex with men (MNSM) attending the largest sexual health clinic in Wuxi, China.

METHODS

A questionnaire about participants' socio-demographic characteristics and view on HPV vaccination was collected.

RESULTS

A total of 186 MSM and 182 MNSM were recruited. Among MSM, 12.4% were under 20 years old, 64.5% never married and 56.5% from Jiangsu Province (where Wuxi City is located); 64.0% had resided in Wuxi for over 2 years, 64.5% had high school education or more, and 83.9% had an income of 5000 RMB or less per month compared to figures of 5.5%, 50.6%, 73.6%, 54.9%, 86.8% and 64.8% among MNSM, respectively (All P values < 0.05). Among these 2 groups of men, 18.4% and 23.1% had heard of HPV; 10.2% and 15.4% had heard of HPV vaccine; and 26.2% and 20.2% would take HPV vaccine before sexual debut, respectively. MNSM were significantly more willing to take HPV vaccine than MSM (70.9 vs 34.9%, p < 0.001). Factors associated with HPV vaccine acceptance among MSM included engaging mostly in receptive anal sex (Odds ratio (OR)=3.9, 95% Confidence interval (CI): 1.8-13.5), never using a condom in anal sex in the past 6 months (3.5, 1.5-20.2), ever diagnosed with a sexually transmitted infection (STI) (3.4, 1.3-8.4) and ever receiving HIV related services (1.6, 1.1-4.4). Among MNSM these Factors included commercial sex with women (1.7, 1.2-8.6), never using a condom in commercial sex (1.6, 1.4-7.6) and STI diagnosis (2.0, 1.6-7.3).

CONCLUSIONS

Sexually active MSM and MNSM in Wuxi lacked knowledge of HPV and HPV vaccination. The majority of these at-risk men would not benefit from HPV vaccination as their age at first sex proceeded perceived age of vaccine uptake. Aggressive education aimed at increasing knowledge of HPV and HPV vaccination among these men is warranted.

How to best measure the effectiveness of male human papillomavirus vaccine programmes?

In many countries now, vaccination of young adolescent girls with prophylactic human papillomavirus (HPV) vaccines has been rolled out as a public health programme. In countries where coverage has been high, this has led to dramatic reductions in cervical high-grade precancerous lesions, as well as genital warts. A reduction in circulating vaccine-related HPV types has also been demonstrated. With the introduction of gender-neutral approaches incorporating universal vaccination of pre-adolescent boys in some countries, implementation of post-vaccine monitoring will be critical to evaluate the incremental impact of male vaccination. In contrast to cervical screening programmes, population-wide screening for HPV infection or related disease in males is not recommended; hence real-time monitoring of HPV vaccine effectiveness in males will require dedicated surveillance strategies. Monitoring the prevalence of circulating genital HPV types using a sentinel surveillance model could offer a good surrogate marker of early vaccine effectiveness in males. However, such an approach requires careful consideration of the most appropriate anatomical sites from which to collect specimens, the best sampling methods and the most sensitive assays to use. Additionally, in assessing an accurate measure of the impact of HPV vaccination in the male population, the effect of herd protection will need to be assessed, as most male programmes will commence in the setting of established female programmes. This poses an interesting epidemiological challenge.