Human papillomavirus infections among couples in new sexual relationships

Epidemiology of genital human papillomavirus infections in sequential male sex partners of young females

OBJECTIVES

Couple-based studies have considered human papillomavirus (HPV) transmission between current heterosexual partners (male↔female). Using data from young women and their sequential male partners, we analysed HPV transmission from upstream sexual partnerships (male 1↔female) to downstream sex partners (→male 2).

METHODS

Among 502 females enrolled in the HPV Infection and Transmission among Couples through Heterosexual activity study (2005-2011, Montréal, Canada), 42 brought one male sex partner at baseline (male 1) and another during follow-up (male 2). Female genital samples, collected at six visits over 24 months, and male genital samples, collected at two visits over 4 months, were tested for 36 HPV types (n = 1512 detectable infections). We calculated observed/expected ratios with 95% CIs for type-specific HPV concordance between males 1 and 2. Using mixed-effects regression, we estimated ORs with 95% CIs for male 2 testing positive for the same HPV type as male 1.

RESULTS

Detection of the same HPV type in males 1 and 2 occurred 2.6 (CI 1.9-3.5) times more often than chance (29 instances observed vs. 10.95 instances expected). The OR for male 2 positivity was 4.2 (CI 2.5-7.0). Adjusting for the number of times the linking female tested positive for the same HPV type attenuated the relationship between male 1 and 2 positivity, suggesting mediation.

CONCLUSIONS

High type-specific HPV concordance between males 1 and 2 confirms HPV's transmissibility in chains of sequential sexual partnerships. HPV positivity in an upstream partnership predicted positivity in a downstream male when the linking female partner was persistently positive.

Prevention and treatment of human papillomavirus in men benefits both men and women

Men should not be overlooked in research on human papillomavirus (HPV) and its associated genital diseases. This is because men infected with HPV are not only at higher risk of genital cancers, but also increase their partners' risk of HPV infection and reinfection through sexual contact. Herein, we summarized the state of knowledge regarding the prevention and treatment of HPV infection in men as well as the possible effects of the prevention and treatment of HPV in men on their female partners. Condom use, smoking cessation, male circumcision, and HPV vaccination for men each play an important role in preventing HPV infection within heterosexual couples. Additionally, men could choose to test for certain types of HPV, such as the oncogenic HPV16 or HPV18 strains, as part of a routine screening program when their partner is positive for HPV. Although there is no recognized treatment for HPV infection as of yet, immunotherapy drugs, such as toll-like receptor agonists, therapeutic HPV vaccines, and immune checkpoint inhibitors, have shown promising results in clinical trials and in actual clinical practice. HPV infection in men also increases the risk of cervical cancer in their female partners. Because of the high partner concordance for HPV demonstrated in prior research, the prevention and treatment of HPV in men should be explored more comprehensively in future research.

Clinical guideline for the diagnosis and treatment of cutaneous warts (2022)

AIM

Cutaneous warts caused by human papillomavirus are benign proliferative lesions that occur at any ages in human lives. Updated, comprehensive and systematic evidence-based guidelines to guide clinical practice are urgently needed.

METHODS

We collaborated with multidisciplinary experts to formulate this guideline based on evidences of already published literature, focusing on 13 clinical questions elected by a panel of experts. We adopted Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to form classification of recommendations as well as the improved Delphi method to retain respective recommendations with a consensus degree of over 80%.

RESULTS

Our guideline covered aspects of the diagnosis and treatment of cutaneous warts such as diagnostic gold standard, transmission routes, laboratory tests, treatment principle, clinical cure criterion, definitions, and treatments of common warts, flat warts, plantar warts, condyloma acuminatum, and epidermodysplasia verruciformis. Recommendations about special population such as children and pregnant women are also listed. In total, 49 recommendations have been obtained.

CONCLUSIONS

It is a comprehensive and systematic evidence-based guideline and we hope this guideline could systematically and effectively guide the clinical practice of cutaneous warts and improve the overall levels of medical services.

Role of Human Leukocyte Antigen Allele Sharing in Human Papillomavirus Infection Transmission Among Heterosexual Couples: Findings From the Hitch Cohort Study

Background

Human leukocyte antigen (HLA) polymorphism influences innate and adaptive immune responses. Among heterosexual couples in the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) cohort study, we examined whether allele sharing in a couple predicted the partners’ infections with the same human papillomavirus (HPV) type.

Methods

We tested genital samples from 271 couples for 36 HPV genotypes by polymerase chain reaction. We used direct DNA sequencing to type HLA-B07, -DRB1, -DQB1 and -G. Generalized estimating equations were used to examine the associations between the extent of allele sharing and HPV type concordance in which at least 1 of the partners was HPV positive.

Results

We identified 106 different HLA alleles. The most common HLA alleles among couples were G*01:01:01 (95.6%), G*01:01:02 (60.1%), DQB1*03:01 (57.2%), and DRB1*07:01 (46.9%). Allele sharing was as follows: 19.6% shared none, 43.2% shared 1 only, 25.1% shared 2, and 12.5% shared 3–5. Irrespective of HLA class, grouped or in combination, the extent of allele sharing was not a significant predictor of type-specific HPV concordance in a couple (odds ratio, 1.1 [95% confidence interval, .5–2.1], for 3–5 vs none).

Conclusions

We found no evidence that the extent of HLA allele concordance influences the likelihood of HPV transmission in newly formed heterosexual couples.

Proportion of incident genital human papillomavirus detections not attributable to transmission and potentially attributable to latent infections: Implications for cervical cancer screening

BACKGROUND

Infections with human papillomaviruses (HPV) may enter a latent state, and eventually become reactivated following loss of immune control. It is unclear what proportion of incident HPV detections are reactivations of previous latent infections versus new transmissions.

METHODS

The HITCH cohort study prospectively followed young newly-formed heterosexual partners recruited between 2005-2011 in Montréal, Canada. We calculated the fraction of incident HPV detections non-attributable to sexual transmission risk factors with a Bayesian Markov model. Results are the median (2.5-97.5 th percentiles) of the estimated posterior distribution.

RESULTS

544 type-specific incident HPV detection events occurred in 849 participants; 33% of incident HPV detections occurred in participants whose HITCH partners were negative for that HPV type and who reported no other sex partners over follow-up. We estimate that 43% (38-48%) of all incident HPV detections in this population were not attributable to recent sexual transmission and might be potentially reactivation of latent infections.

CONCLUSIONS

A positive HPV test result in many cases may be a reactivated past infection, rather than a new infection from recent sexual behaviors or partner infidelity. The potential for reactivation of latent infections in previously HPV-negative women should be considered in the context of cervical cancer screening.

Sex- and Type-specific Genital Human Papillomavirus Transmission Rates Between Heterosexual Partners: A Bayesian Reanalysis of the HITCH Cohort

BACKGROUND

It is unclear whether sexual transmission rates of human papillomaviruses (HPV) differ between sexes and HPV types. We estimate updated transmission rates from the final HITCH cohort study and propose an estimation method that accounts for interval-censored data and infection clearance.

METHODS

We enrolled young women 18-24 years old and their male sex partners ≥18 years old in Montréal, Canada, between 2005 and 2011. We followed women over 24 months and men over 4 months. We tested genital samples with Linear Array for HPV DNA detection and genotyping. We calculated infection transmission rates between partners using a multistate Markov model via a Bayesian approach. We report the posterior median and 2.5%-97.5% percentile intervals (95% PI).

RESULTS

We observed 166 type-specific incident HPV transmission events in 447 women and 402 men. The estimated median transmission rate from an HPV-positive to a negative partner was 4.2 (95% PI = 3.1 to 5.3) per 100 person-months. The transmission rate from men-to-women was 3.5 (95% PI = 2.5 to 4.7) and from women-to-men was 5.6 (95% PI = 3.8 to 7.0) per 100 person-months, corresponding to a rate ratio of 1.6 (95% PI = 1.0 to 2.5). Partners reporting always using condoms had a 0.22 (95% PI = 0.05 to 0.61) times lower HPV transmission rate than those reporting never using condoms. HPV16/18 did not have particularly high transmission rates relative to other HPV types.

CONCLUSION

Our updated analysis supports previous research suggesting higher women-to-men than men-to-women HPV transmission rates and a protective effect of condoms in heterosexual partnerships. Our results also suggest that crude incidence rates underestimate HPV transmission rates due to interval-censoring. See video abstract at http://links.lww.com/EDE/B794.

Transmission reduction and prevention with HPV vaccination (TRAP-HPV) study protocol: a randomised controlled trial of the efficacy of HPV vaccination in preventing transmission of HPV infection in heterosexual couples

INTRODUCTION

Human papillomavirus (HPV) is a causal agent of malignancies including cervical, vulvar, vaginal, penile, anal and oropharyngeal cancer, as well as benign conditions such as anogenital warts. HPV vaccination protects individuals against infections with the target HPV types and their clinical outcomes. However, little is known about the protection an immunised individual confers to their sexual partner or its impact on HPV transmission dynamics. In this context, the Transmission Reduction and Prevention with HPV vaccination (TRAP-HPV) study was designed to determine the efficacy of an HPV vaccine in reducing transmission of genital and oral HPV infection in sexual partners of vaccinated individuals.

METHODS AND ANALYSIS

The TRAP-HPV study is an ongoing randomised controlled trial among heterosexual couples living in Montreal, Canada. Sexually active couples, aged between 18 and 45 years, who have been in a relationship no longer than 6 months are considered eligible. Participants are independently randomised to receive either the intervention HPV vaccine, Gardasil 9, or a placebo hepatitis A vaccine, Avaxim, creating four vaccination groups among couples: intervention-intervention, intervention-placebo, placebo-intervention and the placebo-placebo. Participants provide genital (vaginal/penile) and oral samples at baseline and five follow-up visits over a 1-year duration. Linear Array HPV genotyping is used to detect 36 HPV types. Cox proportional hazard regression models will be used to estimate the effect of vaccination on HPV transmission.

ETHICS AND DISSEMINATION

The TRAP-HPV study received ethical approval by institutional review boards McGill University, Concordia University and Centre Hospitalier de l'Université de Montréal. Before enrolment, all participants provide informed written consent. Results will be published in peer-reviewed journals and presented at national and international conferences. The generated empirical evidence could be used in mathematical models of vaccination to inform policymakers in Canada and elsewhere.

TRIAL REGISTRATION NUMBER

NCT01824537.

Prevalence, Concordance, and Transmission of Human Papillomavirus Infection Among Heterosexual Couples in Liuzhou, China: An Observational Perspective Study

BACKGROUND

Knowledge of human papillomavirus (HPV) transmission dynamics, which have important public health implications for designing HPV vaccination strategies, is scarce in undeveloped areas.

METHODS

From May to July 2014, 390 couples were enrolled from the general population in Liuzhou, China. Exfoliated cells from male penis shaft/glans penis/coronary sulcus (PGC) and perianal/anal canal (PA) sites and from female vaginal, vulvar, and PA sites were collected biannually for 1 year.

RESULTS

The HPV type-specific concordance rate between couples was 15.5% (95% confidence interval [CI], 8.5%-25.0%). For anogenital HPV transmission, the male-to-female transmission rate (11.5 [95% CI, 4.3-30.7] per 1000 person-months) was similar to the female-to-male transmission rate (11.3 [95% CI, 5.9-21.7] per 1000 person-months). The concordance rates between male PGC site and female vaginal, vulvar, and PA sites were 20.0%, 21.8%, and 14.9%, respectively, which were significantly higher than expected by chance. Infections transmitted from males to females seemed mainly originated from male genital sites, whereas for female-to-male transmission, the vaginal, vulvar, and PA sites might be all involved.

CONCLUSIONS

Among the heterosexual couples with relatively conservative sexual behavior, the anogenital HPV transmission rate for females to males is similar to that of males to females. In addition to the vagina and vulva, the female PA site is also an important reservoir for HPV transmission.

Detection of Incident Anal High-Risk Human Papillomavirus DNA in Men Who Have Sex With Men: Incidence or Reactivation?

Background

We aimed to assess whether sexual exposure may explain all incident anal human papillomavirus (HPV) detections among men who have sex with men (MSM).

Methods

A longitudinal study among MSM was conducted between 2010 and 2013 with visits every 6 months and up to 24 months of follow-up. Risk-factor questionnaires, blood samples, and anal and penile self-swabs were collected at each visit. Self-swabs were used for detection and genotyping of HPV by the broad spectrum L1 based SPF10 PCR DNA/enzyme immunoassay LiPA25 system. Serum samples were tested for high-risk HPV (hrHPV) antibodies. Incident anal HPV detection rates among sexually non-, low, and highly exposed MSM were compared. Factors associated with incident anal hrHPV detection were assessed using multivariable Cox regression.

Results

Seven hundred fourteen men (median age, 40 years; 39% human immunodeficiency virus [HIV] infected) were included in the analysis. Incident anal detections of all hrHPV types were observed among both sexually nonexposed and exposed MSM. In multivariable analyses, being highly sexually exposed, being HIV infected, and having a penile HPV infection were positively associated with incident anal HPV detection; those reporting more sex partners had a nonsignificantly increased risk of HPV detection.

Conclusions

Incident anal hrHPV detection is common among recently nonexposed MSM, suggesting that a reactivated latent HPV infection instead of an incident infection may underlie incident HPV detection.

Human papilloma virus (HPV) genotypes concordance between Iranian couples referrals

Background

Human Papilloma Virus (HPV) genotypes concordance among sexual couples has been evaluated in many investigations with considerable variations in the concordance. However, no such study has carried out between Iranian couples yet.

Methods

Urogenital specimen from both males and females of couples were taken and transferred to Nilou laboratory for molecular analysis. HPV DNA extraction and typing were carried out using cobas 4800 platform. Demographic and virological data were analyzed afterwards.

Results

One hundred fourteen couples were enrolled in the study. The mean age of participants were 36 ± 8 and 32 ± 7 for males and females, respectively. 64 (28%) of specimens were positive for at least one HPV genotype. The positive rates within genders were 30.7 and 25.4% for females and males, respectively with a considerable association (P value 0.021). Within the positive samples, 13(5.7%), 8 (7%) and 31(13.5%) were belonged to 16, 18 and other HR genotypes. 59 (51.8%) couples who were negative for HPV showed negative concordance. Of the total positive HPV patients (55 couples, 48.2%), 9 (16.3%) couples had positive concordance and the rest of 46 (83.7%) couples (either of spouse being negative and the other being positive for HPV) showed neither kinds of concordance.

Conclusion

Recognition of the dynamics of HPV infection not only in women, but in their sexual partners could impact the implementation of preventive measures like HPV vaccination for cervical cancer and other HPV-related diseases for both sexual partners.

Vaccination of Young Women Decreases Human Papillomavirus Transmission in Heterosexual Couples: Findings from the HITCH Cohort Study

BACKGROUND

Vaccination against human papillomaviruses (HPV) prevents HPV infections and, consequently, cervical lesions. However, the effect of vaccination on HPV transmission within couples is unknown.

METHODS

We used data from HITCH, a prospective cohort study of heterosexual couples (women ages 18-24 years) in Montreal, 2005 to 2013. Vaccination history was self-reported. Genital samples were tested for HPV DNA by PCR (linear array). Type-specific viral loads were quantified using real-time PCR. OR and HR were estimated using multilevel mixed-effects logistic regression and a parametric model for interval- censored survival-time data, respectively. Differences in viral loads were evaluated using the Friedman ANOVA test.

RESULTS

Among 497 couples, 12, 16, and 35 women received 1, 2, or 3 vaccination doses at baseline, respectively. Median age at vaccination was 18 years. Most women (92.1%) had their first coitus before vaccination. At baseline, partner concordance of persistent HPV6/11/16/18 infections was lower in vaccinated than unvaccinated women [adjusted OR = 0.10; 95% confidence interval (CI), 0.01-0.65] but not for non α7/α9/α10-HPV types (adjusted OR = 1.00; 95% CI, 0.44-2.29). Incidence of persistent α7/α9/α10 HPV types in women was inversely associated with vaccination status at baseline (adjusted HR = 0.12; 95% CI, 0.03-0.47). Likewise, male partners of vaccinated women had a lower incidence of α7/α9/α10 HPV infections (adjusted OR = 0.22; 95% CI, 0.05-0.95). Vaccinated women with HPV 6/11/16/18 infections had lower viral loads (P = 0.001) relative to unvaccinated women.

CONCLUSIONS

Vaccination of sexually active women significantly reduced transmission of α7/α9/α10 HPV types in heterosexual couples.

IMPACT

These results underscore and quantify the positive effect of HPV vaccination on HPV transmission within heterosexual couples.

Human Papillomavirus Viral Load and Transmission in Young, Recently Formed Heterosexual Couples

BACKGROUND

We studied the association between human papillomavirus (HPV) viral load (VL) and HPV concordance.

METHODS

The HITCH cohort study included young, heterosexual, recently formed, sexually active couples. Questionnaires and genital samples were collected at 0 and 4 months. Samples were tested for HPV DNA by polymerase chain reaction (PCR; Linear Array). VLs of HPV6/11/16/18/31/42/51 were quantified using type-specific real-time PCR. Correlations between VL and type-specific HPV prevalence and incidence were evaluated using multilevel, mixed-effects linear/logistic regression models.

RESULTS

We included 492 couples. VLs were higher in penile than vaginal samples. VL at subsequent visits correlated significantly within men (r, 0.373), within women (r, 0.193), and within couples (r range: 0.303-0.328). Men with high VL had more type-specific persistent HPV infections (odds ratio [OR], 4.6 [95% confidence interval {CI}, 2.0-10.5]). High VL in men was associated with prevalent (OR, 5.3 [95% CI, 2.5-11.2]) and incident (OR, 6.7 [95% CI, 1.5-30.7]) type-specific HPV infections in their partner. Women's VL was associated with type-specific HPV prevalence in their partner at the same (OR, 5.9) and subsequent (OR, 4.7) visit.

CONCLUSIONS

Persistent HPV infections have limited VL fluctuations. VL between sex partners are correlated and seem predictive of transmission episodes.

Exploration of the effect of human papillomavirus (HPV) vaccination in a cohort of pregnant women in Montreal, 2010-2016

HPV vaccination efficacy has been shown in clinical trials but it is important to verify population level vaccine effectiveness (VE). We aimed to explore VE and herd effect using HPV infection data from a cohort study of Canadian pregnant women. We analyzed the baseline data of the HERITAGE study, which includes pregnant women recruited in Montreal between 2010-2012 and 2015–2016. Cervicovaginal samples self-collected in the first trimester were tested for 36 HPV types. Vaccination status was self-reported. VE and 95% confidence intervals (CI) were estimated by comparing the prevalence of HPV between vaccinated and unvaccinated women. Herd effect was explored by comparing HPV prevalence in unvaccinated women between the 2 recruitment periods. Adjusted ORs (95%CI) were estimated using exact logistic regression. The proportion of vaccinated women with at least one dose of 4vHPV was 7.5%. Although most of them were vaccinated after the onset of sexual activity, a high VE was found for HPV-16/18 (86.1% (95%CI: 15.0–99.7)). For HPV-6/11/16/18 and for HPV-31/33/45, VE was 61.9% (-23.5–92.6) and 57.0% (-47.7–92.0%), respectively. We also observed a non-statistically significant reduction in the prevalence of HPV-6/11/16/18 and HPV-31/33/45 among unvaccinated women recruited during the second recruitment period (adjusted OR: 0.8 (0.4–1.8) and 0.8 (0.3–1.7), respectively).

Hand-to-genital and genital-to-genital transmission of human papillomaviruses between male and female sexual partners (HITCH): a prospective cohort study

BACKGROUND

Hand-to-genital contact is hypothesised to be a transmission mode of human papillomavirus (HPV) of the Alphapapillomavirus genus. We compared the relative importance of hand-to-genital and genital-to-genital HPV transmission between sexual partners.

METHODS

In this prospective cohort study, we recruited and followed up female university students aged 18-24 years and their male sexual partners in Montreal, QC, Canada (2005-11). Participants were eligible if they had initiated sexual activity within the past 6 months. Women were examined at clinic visits at baseline and every 4-6 months for up to 24 months. Men had a baseline visit and a single follow-up visit approximately 4 months later. Partners provided hand and genital swab samples, which we tested for DNA of 36 HPV types using PCR. We assessed predictors of incident type-specific HPV detections using Cox proportional hazards models.

FINDINGS

Participants were recruited between June 5, 2006, and April 4, 2013. 264 women and 291 men had valid hand samples. The hazard ratio (HR) of incident detection of HPV in genital samples from women was 5·0 (95% CI 1·5-16·4) when her partner was positive for the same HPV type on his hand versus negative, but adjustment for his genital HPV status reduced the HR to 0·5 (0·1-1·8). Similarly, the HR of incident detection of HPV on men's genitals was 17·4 (95% CI 7·9-38·5) when his partner was positive for the same HPV type on her hand versus negative, but adjustment for her genital HPV status reduced the HR to 2·3 (0·9-6·2). Conversely, the HR of type-specific incident detection of HPV in genital samples associated with partner genital HPV positivity was 19·3 (95% CI 11·8-31·8) for women and 28·4 (15·4-52·1) for men after adjustment for their hand HPV status.

INTERPRETATION

Clinicians can reassure their patients that HPV transmission is unlikely to occur through hand-to-genital contact. The majority of genital HPV infections are likely to be caused by genital-to-genital sexual transmission.

FUNDING

Canadian Institutes for Health Research, National Institutes of Health, Fonds de la Recherche en Santé du Québec, and Merck & Co.

Human Papillomavirus Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) Cohort Study: Protocol Describing Design, Methods, and Research Goals

BACKGROUND

Human papillomavirus (HPV) epidemiological research has generally been individual based, typically focusing on women, with couple-based research mostly consisting of cross-sectional assessment of prevalent HPV infection in both partners.

OBJECTIVE

The HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) study was set up to investigate the transmissibility of HPV among young, recently formed couples in Montreal, Canada. This paper provides an overview of the HITCH cohort study design and procedures as well as a narrative summary of the most important findings.

METHODS

HITCH is a longitudinal investigation of HPV transmission in recently formed heterosexual partnerships initiated within 6-month pre-enrollment, a time at which considerable transmission is believed to occur. A total of 549 newly formed dyads were recruited (2005-2011) from postsecondary institutions, including 502 young women and their male partners. An additional 46 males were enrolled at follow-up, as some women enrolled a subsequent partner at follow-up. Women aged 18-24 years were followed for 24 months for acquisition of HPV types not present at enrollment, whereas men returned for a single follow-up visit at month 4, for a sum total of 3361 clinic visits. The last follow-up visit occurred in January 2014. Extensive sociodemographic, sexual behavioral, and medical history data were collected every 2-4 months using computer-assisted, self-administered questionnaires. Furthermore, participants provided genital, blood, oral, and hand specimens for HPV assessment.

RESULTS

Although in its early analysis stage, HITCH has produced important publications. Findings from HITCH have increased the available knowledge about the natural history of HPV transmission and its determinants, provided further evidence regarding oral-oral and oral-genital routes of HPV transmission, and supplied empirically valid epidemiological parameters of HPV transmission to assist mathematical modelers in health economic assessments. In addition, HITCH data were made available to several multistudy collaborations evaluating new HPV detection assays and evidence for-or-against HPV type replacement following the introduction of HPV vaccination.

CONCLUSIONS

HITCH will continue to offer a unique resource for research on HPV transmission.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/11284.

Y Chromosome DNA in Women's Vaginal Samples as a Biomarker of Recent Vaginal Sex and Condom Use With Male Partners in the HPV Infection and Transmission Among Couples Through Heterosexual Activity Cohort Study

BACKGROUND

Y chromosome DNA from male epithelial and sperm cells was detected in vaginal samples after unprotected sex in experimental studies. We assessed the strength of this association in an observational setting to examine the utility of Y chromosome DNA as a biomarker of recent sexual behaviors in epidemiological studies.

METHODS

The HPV (human papillomavirus) Infection and Transmission Among Couples Through Heterosexual Activity cohort study enrolled 502 women attending a university or college in Montréal, Canada, and their male partners from 2005 to 2010. Participants completed self-administered questionnaires. We used real-time polymerase chain reaction to test women's baseline vaginal samples for Y chromosome DNA and assessed which sexual behaviors were independent predictors of Y chromosome DNA positivity and quantity with logistic and negative binomial regression.

RESULTS

Y chromosome DNA positivity decreased from 77% in women in partnerships reporting vaginal sex 0 to 1 day ago to 13% in women in partnerships reporting last vaginal sex of 15 or more days ago (adjusted odds ratio, 0.09; 95% confidence interval, 0.02-0.36). The mean proportion of exfoliated vaginal sample cells with Y chromosome DNA was much lower for women who reported always using condoms (0.01%) than for women who reported never using condoms (2.07%) (adjusted ratio, 26.8; 95% confidence interval, 8.9-80.5). No association was found with reported oral/digital sex frequency or concurrency of partnerships.

CONCLUSIONS

Y chromosome DNA quantity is strongly associated with days since last vaginal sex and lack of condom use in observational settings. Y chromosome DNA quantity may prove useful as a correlate of recent vaginal sex in observational studies lacking data on sexual behavior, such as surveillance studies of human papillomavirus infection prevalence.

Human Immunodeficiency Virus/AIDS, Human Papillomavirus, and Anal Cancer

Anal cancer is an increasingly common non-AIDS-defining cancer among individuals infected with the human immunodeficiency virus (HIV). It is associated with human papillomavirus (HPV). HPV16 is the most common genotype detected in anal cancers. The HPV types detected in anal cancer are included in the 9-valent vaccine. HPV vaccines have demonstrated efficacy in reducing anal precancerous lesions in HIV-infected individuals. Standard treatment has been fluorouracil and mitomycin (or cisplatin) plus radiation. Continued studies are needed to test new treatment strategies in HIV-infected patients with anal cancer to determine which treatment protocols provide the best therapeutic index.

Assortativity and Mixing by Sexual Behaviors and Sociodemographic Characteristics in Young Adult Heterosexual Dating Partnerships

BACKGROUND

Assortative sexual mixing, the tendency for individuals to choose partners with similar characteristics to themselves, may be an important contributor to the unequal distribution of sexually transmitted infections in populations. We analyzed the tendency for assortative mixing on demographic and sexual behaviors characteristics in newly formed young adults dating partnerships.

METHODS

Women aged 18 to 24 years and their male sexual partners of no more than 6 months were recruited during 2005 to 2010 at universities in Montreal, Canada. New dating partners were also prospectively recruited during the 2-year follow-up. We used Spearman and Newman coefficients to examine correlations between partners' demographic characteristics and sexual behaviors, and multivariable logistic modeling to determine which characteristics were assortative.

RESULTS

Participants in 502 recruited partnerships were assortative on age (Spearman P = 0.60), smoking behavior (P = 0.43), ethnicity (Newman coefficient=0.39), lifetime number of sexual partners (P = 0.36), sex partner acquisition rates (P = 0.22), gap length between partnerships (P = 0.20), and on whether they had concurrent partners (P = 0.33). Partners were assortative on number of lifetime partners, sexual partner acquisition rates, concurrency, and gap length between partnerships even after adjustment for demographic characteristics. Reported condom use was correlated between initial and subsequently recruited partners (P = 0.35). There was little correlation between the frequencies of vaginal/oral/digital/anal sex between subsequent partnerships.

CONCLUSIONS

Dating partnerships were substantially assortative on various sexual behaviors as well as demographic characteristics. Though not a representative population sample, our recruitment of relatively new partnerships reduces survivor bias inherent to cross-sectional surveys where stable long-term partnerships are more likely to be sampled.

Estimating HPV DNA Deposition Between Sexual Partners Using HPV Concordance, Y Chromosome DNA Detection, and Self-reported Sexual Behaviors

Background

Detection of human papillomavirus (HPV) DNA in genital samples may not always represent true infections but may be depositions from infected sexual partners. We examined whether sexual risk factors and a biomarker (Y chromosome DNA) were associated with genital HPV partner concordance and estimated the fraction of HPV detections potentially attributable to partner deposition.

Methods

The HITCH study enrolled young women attending a university or college in Montréal, Canada, and their male partners, from 2005 to 2010. We tested baseline genital samples for Y chromosome DNA and HPV DNA using polymerase chain reaction.

Results

Type-specific HPV concordance was 42.4% in partnerships where at least one partner was HPV DNA positive. Y chromosome DNA predicted type-specific HPV concordance in univariate analyses, but in multivariable models the independent predictors of concordance were days since last vaginal sex (26.5% higher concordance 0-1 vs 8-14 days after last vaginal sex) and condom use (22.6% higher concordance in never vs always users). We estimated that 14.1% (95% confidence interval [CI], 6.3-21.9%) of HPV DNA detections in genital samples were attributable to vaginal sex in the past week.

Conclusions

A substantial proportion of HPV DNA detections may be depositions due to recent unprotected vaginal sex.

Low prevalence of vaccine-type HPV infections in young women following the implementation of a school-based and catch-up vaccination in Quebec, Canada

BACKGROUND

In Quebec, Canada, a school-based HPV vaccination for girls has been offered since 2008. The vaccine used in the program targets HPV16/18, responsible for ∼70% of cervical cancers and HPV6/11, responsible for the majority of anogenital warts. The objective of this study was to assess the prevalence of HPV in vaccinated and unvaccinated women.

METHODS

Women aged 17-29 years were eligible to participate. Participants' age, vaccination status and diverse risk factors were assessed by a computer-assisted questionnaire. Biological specimens were obtained by self-sampling. HPV genotyping was performed by Linear Array.

RESULTS

A total of 2,118 women were recruited. 2,042 completed the questionnaire and 1,937 provided a vaginal sample. Vaccination coverage varied from 83.5% in women aged 17-19 to 19.1% in those aged 23-29. The overall prevalence of HPV in sexually active women was 39.4% (95%CI: 37.0-41.7) and 56.7% of infected women had multiple type infections. The prevalence of vaccine HPV types varied by age and vaccination status except for women aged 23-29 for whom similar results were observed. Vaccine HPV types were detected in 0.3%, 1.4% and 10.5% of vaccinated women aged 17-19, 20-23, and 23-29 (p<0.05), respectively. HPV16 or HPV18 were detected in 10 women having received at least one dose of vaccine. Nine of these women were already sexually active at the time of vaccination.

CONCLUSION

Infections with HPV types included in the vaccine are rare in women aged less than 23 years and are virtually absent in those who received at least one dose of vaccine before sexual debut.

Concordance of HPV-DNA in cervical dysplasia or genital warts in women and their monogamous long-term male partners

Transmission of human papillomavirus (HPV) is a premise for development of cervical dysplasia and genital warts (GWs). This cross-sectional study assesses concordance of HPV types present in GWs or cervical dysplasia in women and genital infection of their monogamous male partners in conjunction with seroprevalence of HPV-6, -11, -16, and -18 antibodies. Blood was taken from both women and men, as well a smear of the urogenital area of men. HPV DNA detection in women was done in fixed paraffin embedded tissues under histological control. Of 143 couples who agreed to participate in the study, 68 met inclusion criteria. Type-specific concordance was observed in 32.5% (13/40) of couples in which women had genital warts and in 32.1% (9/28) of couples in which women had cervical dysplasia. In multivariate analysis only smoking in women was associated with concordance (P < 0.05). Prevalence of HPV-specific antibodies was high in male partners, but was not associated with presence of the same HPV type on their genitals. The same type-specific HPV antibodies were detected in 81.8% of men in couples with HPV-6 concordant genital warts, but only in 14.3% of men in couples with HPV-16 concordant cervical dysplasia (P < 0.01). These results suggest that type-specific HPV concordance in genital warts and cervical dysplasia lesions of women and genital infection of their male partners is common and similar. Higher seroconversion in couples with HPV-6 concordant genital warts compared with couples with HPV-16 concordant cervical dysplasia may be explained by viral load exposure.

Trends and Determinants of Human Papillomavirus Concordance Among Human Immunodeficiency Virus-Positive and -Negative Heterosexual Couples in Rakai, Uganda

Background

Limited data are available on human papillomavirus (HPV) infection among human immunodeficiency virus (HIV)-negative or HIV-positive couples followed longitudinally.

Methods

Genital HPV was assessed in 725 concordant HIV-negative couples and 209 HIV-positive couples enrolled in a male circumcision trial in Rakai, Uganda, using the Roche Linear Array assay, which detects 37 HPV genotypes. Human papillomavirus prevalence and determinants of genotype-specific concordance were assessed at annual visits. Cumulative detection of HPV genotypes over 2 years was also assessed.

Results

At enrollment, HPV infection was detected in 54% of HIV-negative women, 56% of HIV-negative men, and 93% of HIV-positive men and women. For HIV-negative couples, genotypic concordance was 30% at baseline (n = 219/725) and declined significantly with age (adjusted prevelance risk ratio [adjPRR] = 0.53; 95% confidence interval [CI] = 0.28-0.93 comparing women aged >40 years to those aged 15-19 years) and male circumcision (adjPRR = 0.60; 95% CI = 0.47-0.77) and increased among couples with recent intercourse (adjPRR = 1.26; 95% CI = 1.04-1.53). These associations were not seen in HIV-positive couples. Among couples with HPV results at all visits, ≥1 of the same genotypes were detected in both partners in 60% of HIV-negative couples and 96% of HIV-positive couples over 2 years.

Conclusion

Human papillomavirus genotype-specific concordance is more common in HIV-positive couples, and irrespective of HIV status, the majority of couples exhibit HPV concordance over 2 years.

Ethnic Variations in Perception of Human Papillomavirus and its Vaccination among Young Women in Nepal

BACKGROUND

The Human Papillomavirus (HPV) is strongly associated with cervical and other cancers. In women, cervical cancer is the third most common cancer. HPV infection can be largely prevented through vaccination of (adolescent) girls. At the same time, Nepal is a low-income country experiencing a cultural change in attitudes towards sex and sexual behaviour. However, in the adolescent population knowledge about HPV, factors associated with an increased risk of HPV and the existence of the vaccination is often low.

MATERIALS AND METHODS

This was a cross-sectional study with female students enrolled in health and non-health science courses in Pokhara, Nepal. The questionnaire included demographic details, knowledge and attitude questions related to HPV, associated risk behaviour and its vaccination. Descriptive statistics, including Chi-Square test, were used to identify statistically significant relationships. Ethical approval was granted by the relevant authority in Nepal.

RESULTS

Hindu religion (75.0 %; 95% CI: 70.9, 78.6) and Newari caste (75.5%; CI: 61.1, 86.7) were more aware about HPV, HPV vaccination. Hindus religion (55.6%; 95% CI: 51.2, 60.0) and Dalit caste (61.6%, 95% CI: 53.3, 69.4) more willing to be vaccinated than other religions and other castes, respectively. Not unsurprisingly, students on health-related courses had a greater awareness of HPV, HPV vaccination and were more willing to be vaccinated than students on other courses. Similar patterns of association arose for knowledge related to those sexually active at an early age; HPV risk and multiple sex partners; and fact that condoms cannot fully prevent the transmission of HPV.

CONCLUSION

Knowledge about the link between HPV and (a) early sexual initiation, (b) having multiple sexual partners, and (c) the limited protection of condoms and other birth control measures was poor in our study compared to similar research conducted in other parts of the world. One key implication is the need for education campaigns in Nepal to educate young women and their parents about HPV, its risk factors and the benefits of vaccination. .

Epidemiologic Evaluation of Human Papillomavirus Type Competition and the Potential for Type Replacement Post-Vaccination

Background

Millions of women have been vaccinated with one of two first-generation human papillomavirus (HPV) vaccines. Both vaccines remain in use and target two oncogenic types (HPVs 16 and 18); however, if these types naturally compete with others that are not targeted, type replacement may occur following reductions in the circulating prevalence of targeted types. To explore the potential for type replacement, we evaluated natural HPV type competition in unvaccinated females.

Methods

Valid HPV DNA typing information was available from five epidemiological studies conducted in Canada and Brazil (n = 14,685; enrollment across studies took place between1993 and 2010), which used similar consensus-primer PCR assays, capable of detecting up to 40 HPV types. A total of 38,088 cervicovaginal specimens were available for inclusion in our analyses evaluating HPV type-type interactions involving vaccine-targeted types (6, 11, 16, and 18), and infection with each of the other HPV types.

Results

Across the studies, the average age of participants ranged from 21.0 to 43.7 years. HPV16 was the most common type (prevalence range: 1.0% to 13.8%), and in general HPV types were more likely to be detected as part of a multiple infection than as single infections. In our analyses focusing on each of the vaccine-targeted HPV types separately, many significant positive associations were observed (particularly involving HPV16); however, we did not observe any statistically significant negative associations.

Conclusions

Our findings suggest that natural HPV type competition does not exist, and that type replacement is unlikely to occur in vaccinated populations.

Intention of college students to receive the human papillomavirus vaccine

Purpose

– The purpose of this paper is to better understand what influences the intentions of college students to receive the human papillomavirus (HPV) vaccine. HPV is the most common sexually transmitted infection in the USA and cancers related to HPV are on the rise.

Design/methodology/approach

– A 2×2 experimental design was used to predict the intentions. Messages were created that manipulated the level of severity and vulnerability to determine which would increase intentions to receive the HPV vaccine. Each of the 278 participants viewed a message that contained one severity message (high or low) and one vulnerability message (high or low).

Findings

– Regression was used to determine that elements of the protection motivation theory such as vulnerability and fear, along with norms, and information seeking explained a significant portion of the variance in intent to be vaccinated (R2=0.40, F(4, 268)=44.47, p < 0.001). Norms had the most influence on intention (β=0.42, p < 0.001), next was vulnerability (β=0.21, p < 0.001) then fear (β=0.16, p=0.002), and finally information seeking (β=0.10, p=0.01).

Originality/value

– The current college age population did not have the opportunity to be vaccinated early and the recent (2011) recommendation that males get vaccinated makes this research valuable to those designing vaccination messages. The current study shows that norms were the most influential variable in regards to increasing intent to get vaccinated. This means that if the participant believed their friends would support or endorse their intent to get vaccinated they were more likely to say they would follow through and get vaccinated. This finding should be highlighted in any future campaign.

Cervical Infection With Vaccine-Associated Human Papillomavirus (HPV) Genotypes as a Predictor of Acquisition and Clearance of Other HPV Infections

BACKGROUND

Recent birth cohorts vaccinated against human papillomavirus (HPV) may be protected against up to 4 genotypes (HPV-6, -11, -16, and -18). If natural competition exists between these and other HPV types, then the prevalence of other types may increase after vaccination.

METHODS

Cohort information from 3 studies was used to compare acquisition and clearance of 30 different HPV types (individually and grouped by species), according to infection status with vaccine-targeted types at baseline and the time of the index infection, respectively. Hazard ratios (HRs) were adjusted for predictors of multiple-type infection.

RESULTS

Among 3200 females across all studies, 857 were infected with HPV at baseline, and 994 acquired new infections during follow-up. Females infected with HPV-16 were at higher risk of acquiring other α-9 HPV types (HR, 1.9; 95% confidence interval [CI], 1.2-3.0) but at similar risk of clearing existing α-9 HPV infections (HR, 0.9; 95% CI, .7-1.3). Females infected with vaccine-targeted types were generally at higher risk of acquiring additional types (HRs, > 1.0) and at equal risk of clearing existing infections. Accounting for multiple comparisons, none of the HRs of < 1.0 or >1.0 were statistically significant in our analyses of acquisition or clearance.

CONCLUSIONS

Vaccine-targeted HPV types do not appear to compete with other types, suggesting that HPV type replacement is unlikely to occur.

Concurrence of oral and genital human papillomavirus infection in healthy men: a population-based cross-sectional study in rural China

Human papillomavirus (HPV) infection, a primary cause of genital cancer, is also related to the increasing incidence of oropharyngeal cancer among young men. Relatively little is known about the concurrence of oral and genital infection among healthy individuals. Oral and genital swab exfoliated cells were collected simultaneously from 2566 men in rural China. Using general primer-mediated (SPF1/GP6+) PCR and sequencing, HPV testing results were obtained from 2228 men with both valid oral and genital specimens (β-globin-positive). The prevalence of HPV infection was 6.7% in the oral cavity and 16.9% for the external genitalia. Among 43 men (1.9%, 43/2228) with oral-genital coinfection, 60.5% (26/43) harbored an identical HPV type at both sites. The risk of oral HPV infection was higher among men with genital infection than among uninfected men (11.4% vs. 5.7%, Adjusted OR = 2.3, 95% CI: 1.6-3.4). In addition, having multiple lifetime sexual partners was a significant risk for oral-genital HPV coinfection (Adjusted OR = 2.6, 95% CI: 1.0-7.0; 2 partners vs. 1 partner). These findings provide a basis for further understanding the natural history and transmission dynamics of oral HPV infection.

Transmission of genital human papillomavirus infection in couples: a population-based cohort study in rural China

HPV transmission dynamics have rarely been studied in the general population, especially in China. We followed the genital HPV infection status of both partners in 874 couples aged 25-65 years from rural China for up to 7 bi-annual visits during 2009-2013. The positive HPV concordance and transmission rate for partners in a couple were evaluated and relevant risk factors were assessed. The concordance of any, oncogenic, and non-oncogenic HPV was 15.52%, 16.18% and 10.41%, respectively. Male-to-female transmission rate was 7.11, 12.13 and 4.77/1000 person months for any, oncogenic and non-oncogenic HPV respectively. The female-to-male transmission rate was 5.56, 2.37, and 17.01/1000 person months for any, oncogenic and non-oncogenic HPV respectively. The risk of male-to-female transmission was significantly higher than that of female-to-male transmission for oncogenic types. However, for non-oncogenic types, the risk of male-to-female transmission was significantly lower than that of female-to-male transmission. Younger couples, persistent infection with HPV, higher numbers of sexual partners and higher frequency of sexual intercourse were positively associated with HPV transmission in couples. Our results indicate that men in rural China play a more important role than men in western populations as a source of cervical oncogenic HPV infection in women.

Analysis of longitudinal multivariate outcome data from couples cohort studies: application to HPV transmission dynamics

We consider a specific situation of correlated data where multiple outcomes are repeatedly measured on each member of a couple. Such multivariate longitudinal data from couples may exhibit multi-faceted correlations which can be further complicated if there are polygamous partnerships. An example is data from cohort studies on human papillomavirus (HPV) transmission dynamics in heterosexual couples. HPV is a common sexually transmitted disease with 14 known oncogenic types causing anogenital cancers. The binary outcomes on the multiple types measured in couples over time may introduce inter-type, intra-couple, and temporal correlations. Simple analysis using generalized estimating equations or random effects models lacks interpretability and cannot fully utilize the available information. We developed a hybrid modeling strategy using Markov transition models together with pairwise composite likelihood for analyzing such data. The method can be used to identify risk factors associated with HPV transmission and persistence, estimate difference in risks between male-to-female and female-to-male HPV transmission, compare type-specific transmission risks within couples, and characterize the inter-type and intra-couple associations. Applying the method to HPV couple data collected in a Ugandan male circumcision (MC) trial, we assessed the effect of MC and the role of gender on risks of HPV transmission and persistence.

Human Papillomavirus (HPV) Infections and the Importance of HPV Vaccination

HPV persistence is necessary for the development of anogenital cancer. Studies show that cervical and anal HPV infections in women and in men who have sex with men are common. Clearance of HPV infection is similarly common; few individuals show persistence unless they are HIV-infected. HIV strongly influences the development of cervical and anal cancer, as well as their pre-malignant counterparts. Women with cervical and vulvar HPV-associated lesions have higher rates of anal cancer than the general population. HPV also plays an important role in pathogenesis of head and neck cancers, particularly oropharyngeal cancer. Two commercially available HPV vaccines have been proven to be safe and efficacious against cervical HPV16/18 infections and associated precancerous lesions; one of these has also been shown to prevent HPV16/18-associated anal lesions. The FDA has also just approved a new nonavalent HPV vaccine. HPV vaccines will play an important role in prevention of HPV-associated cancers.

Sexual transmission of oral human papillomavirus infection among men

We estimated the prevalence of oral human papillomavirus (HPV) and assessed risk factors among young heterosexual men participating in the HPV Infection and Transmission among Couples through Heterosexual Activity (HITCH) study. Oral and genital HPV samples were collected from 222 men and their female partners who were participating in the HITCH study, a longitudinal cohort on HPV transmission among heterosexual couples. Demographic and behavioral data were collected through self-administered computer questionnaires and biologic samples were tested with the Linear Array for HPV. Outcome measures were overall and type-specific prevalence of oral HPV. The prevalence of oral HPV among men was 7.2% and was higher among men who were ever smokers (12.2%), in nonmonogamous relationships (17.9%), or had a partner with oral (28.6%) and/or genital (11.5%) HPV infection. Moreover, prevalence increased with frequency of oral sex among men whose partner who had a genital infection with the same HPV type. Our results provide further evidence that oral HPV may be transmitted through either oral-oral or oral-genital routes.

Evaluation of human papillomavirus type replacement postvaccination must account for diagnostic artifacts: masking of HPV52 by HPV16 in anogenital specimens

It has been hypothesized that, following a reduction in human papillomavirus (HPV) vaccine-targeted genotypes, an increase in prevalence of other HPV types may occur due to reduced competition during natural infection. Any apparent postvaccination increase must be distinguished from diagnostic artifacts consequent to consensus PCR assays failing to detect HPV types present in low copy numbers in coinfected specimens (under the assumption that with a drop in vaccine-preventable types there may be increased detection of previously "masked" types). We reanalyzed anogenital specimens to evaluate unmasking of HPV52 that may be caused by elimination of HPV16. Using highly sensitive type-specific real-time HPV52 PCR, we retested 1,200 anogenital specimens (all HPV52 negative according to consensus PCR assays) from six epidemiologic studies (200 specimens/study; 100 HPV16(+)/study). Multivariate logistic regression, with adjustment for age and number of sexual partners, was used to evaluate the association between HPV16 positivity and detection of HPV52. In our pooled analysis (n = 1,196), the presence of HPV16 was positively associated with HPV52 detection [adjusted OR, 1.47; 95% confidence interval (CI), 0.76-2.82]. In our separate (study specific) analyses, a statistically significant association was observed in one study that included HIV-infected males (HIPVIRG study; adjusted OR, 3.82; 95% CI, 1.19-12.26). We observed a positive association between HPV16 viral load (tertiles) and detection of HPV52 (P for trend = 0.003). These results indicate that diagnostic artifacts, resulting from unmasking of HPV52, may occur in some settings in the evaluation of HPV type replacement. Additional studies exploring the extent and severity of unmasking are needed.

Determinants of prevalent human papillomavirus in recently formed heterosexual partnerships: a dyadic-level analysis

BACKGROUND

We studied features that predict the presence of human papillomavirus (HPV) in a new sexual partnership.

METHODS

We analyzed data from the "HPV Infection and Transmission Among Couples Through Heterosexual Activity" (HITCH) Cohort Study of recently formed partnerships ("dyads"). Women aged 18-24 and their male partners were recruited during 2005-2010 in Montreal, Canada. We tested genital swabs for detection of 36 HPV types. We defined HPV in a partnership as the presence of 1 or more HPV types in either or both partners. Using baseline data from 482 dyads, we calculated prevalence ratios to evaluate candidate risk factors.

RESULTS

Most women (88%) were unvaccinated. Sixty-seven percent of dyads harbored HPV. For 49% of dyads, both partners were HPV+. HPV was least prevalent in dyads who were in their first vaginal sex relationship (17%) and was virtually ubiquitous in dyads for which both partners had concurrent partners (96%). Dyads that always used condoms with previous partner(s) were 27% (95% confidence interval, 9%-42%) less likely to have HPV.

CONCLUSIONS

The finding that condom use limited onward spread to future partners is in support of condom promotion to prevent sexually transmitted infections. Ongoing monitoring of HPV in sexual networks is needed, particularly in populations with suboptimal vaccine coverage.

Impact of the quadrivalent HPV vaccine on disease recurrence in men exposed to HPV Infection: a randomized study

INTRODUCTION

Human papillomavirus (HPV) is one of the most common sexually transmitted infections and is the cause of several different diseases in men and women. Although little is known about HPV infection in men, they are also in the risk group of HPV infection and play an important role in transmitting the virus to women.

AIM

To define the efficacy of the HPV vaccine through cross-immunization and its role in clearance of HPV infection, and to assess infection-associated factors in men.

METHODS

This prospective randomized clinical study enrolled 171 evaluable men with genital warts between June 2009 and October 2013. After the initial treatment intervention, 91 patients were randomly assigned to receive HPV vaccine in three doses. Eighty patients were in the control (unvaccinated) group. One hundred-eleven men were single and 60 men were married. Patients who had previous treatment for pre-existing warts and medical disorders that needed chronic treatment or immunosuppression were not included in the randomization. Also 29 men with follow-up less than 12 months and incomplete vaccination were not included.

MAIN OUTCOME MEASURES

The patients were assessed regarding age, condom use, marital status, number of visible genital warts, and smoking status. Post-treatment follow-up was monthly up to 12th month.

RESULTS

Mean age was 34 ± 7.6. One hundred fifteen patients were smokers. For the recurrence of warts, age, smoking, vaccination status were insignificant and marital status was significant in the univariable analysis; only marital status preserved significance (HR: 2.0 CI:1.29-3.12 P = 0.002) in the multivariable analysis including vaccination status, marital status, and smoking.

CONCLUSION

Among the investigated factors vaccination status was not but marital status significantly influenced wart recurrence. Married men had more recurrences in our population. Larger multicenter randomized clinical trials are lacking and seriously required to investigate the therapeutic effect of current quadrivalent HPV vaccine in genital warts.

Type-specific human papillomavirus biological features: validated model-based estimates

Infection with high-risk (hr) human papillomavirus (HPV) is considered the necessary cause of cervical cancer. Vaccination against HPV16 and 18 types, which are responsible of about 75% of cervical cancer worldwide, is expected to have a major global impact on cervical cancer occurrence. Valid estimates of the parameters that regulate the natural history of hrHPV infections are crucial to draw reliable projections of the impact of vaccination. We devised a mathematical model to estimate the probability of infection transmission, the rate of clearance, and the patterns of immune response following the clearance of infection of 13 hrHPV types. To test the validity of our estimates, we fitted the same transmission model to two large independent datasets from Italy and Sweden and assessed finding consistency. The two populations, both unvaccinated, differed substantially by sexual behaviour, age distribution, and study setting (screening for cervical cancer or Chlamydia trachomatis infection). Estimated transmission probability of hrHPV types (80% for HPV16, 73%-82% for HPV18, and above 50% for most other types); clearance rates decreasing as a function of time since infection; and partial protection against re-infection with the same hrHPV type (approximately 20% for HPV16 and 50% for the other types) were similar in the two countries. The model could accurately predict the HPV16 prevalence observed in Italy among women who were not infected three years before. In conclusion, our models inform on biological parameters that cannot at the moment be measured directly from any empirical data but are essential to forecast the impact of HPV vaccination programmes.

Reproductive factors associated to human papillomavirus infection in Iranian woman

OBJECTIVE

In recent years, humman papilomaviruses (HPV) infection is the most common type of sexual trasmitted diseases (STD) in majority of countries. It's a significant source of morbidity and mortality worldwide. In this study, we aimed to compare the history of reproductive disease between two groups of Iranian women with and without HPV infection through colposcopy precedure.

MATERIALS AND METHODS

This case -control study included 210 women reffered to a training gynecology hospital of Tehran University of Medical Science in Tehran. Case group was composed of 70 women with diagnosis of HPV infection, while control group was composed of 140 women with no sign of mentioned-infectious diseases of the control group. Reproductive history was prepared using the standard questionnaire, and obtianed data were analized by SPSS 20.

RESULTS

OUR FINDINGS SHOWED THAT THE RISK FACTORS FOR HPV INFECTION WERE AS FOLLOWS: low parity (p = 0.000), reduction of number of weekly sexual intercourse (p = 0.000), no consumption of oral contraceptive pill (OCP) (p = 0.006), and history of withdrawal contraceptive method (p = 0.001).

CONCLUSION

Improvement of our knowledge about reproductive factors associated with HPV may help us to identify women at risk and to develope different methods of preventive interventions.

Primary prophylactic human papillomavirus vaccination programs: future perspective on global impact

Of the 40 types of human papillomavirus that can infect the mucosal epithelium, four types can now be prevented using prophylactic vaccination. Two of these types (high-risk types 16 and 18) cause 70% of cervical cancers, a proportion of other genital cancers and a subset of head and neck cancers. The low-risk types 6 and 11 cause 90% of genital warts and the disease recurrent respiratory papillomatosis. Thus, if primary HPV vaccination programs can be implemented effectively, the potential for a reduction in global disease burden is great. This article considers the current issues and challenges in delivering primary HPV vaccination programs effectively and the likely impact of the vaccines in both the near and more distant future.

HPV related diseases in males: a heavy vaccine-preventable burden

Human Papillomavirus (HPV) has a significant impact in male's health, as cause of clinical manifestations ranging from genital warts to several cancers of the anogenital and aero-digestive tract. HPV types which most frequently affect men are 6, 11, 16 and 18, included in the HPV quadrivalent vaccine, recently approved for use in males by Food and Drug Administration (FDA) and European Medicines Agency (EMA). Although several data about the safety and efficacy of quadrivalent vaccine are available, the implementation of proper immunization plans dedicate to male's population cannot ignore the knowledge of the characteristics of the disease in men, which in some aspects should be clarify, in particular clearance of type-specific HPV infections and transmission dynamics. Purpose of this review is to summarise the main information about the burden and the natural history of the HPV related disease in males.

Human papillomavirus: what every provider should know

Persistence of human papillomavirus (HPV) infection is necessary for the development of cervical cancer. Additionally, infection with HPV is implicated in the majority of cases of other genital tract malignancies including vulvar, penile, and vaginal cancer. HPV testing and vaccination are a routine part of obstetrical/gynecological clinical practice. With an enhanced public awareness of HPV infections, many patients turn to their obstetricians/gynecologists with questions about transmission, testing, and prevention. In this review, we will discuss the biology of HPV, epidemiology of disease, methods and indications for testing, and vaccination strategies.

Rome Consensus Conference - statement; human papilloma virus diseases in males

BACKGROUND

Human Papillomavirus (HPV) is a very resistant, ubiquitous virus that can survive in the environment without a host. The decision to analyse HPV-related diseases in males was due to the broad dissemination of the virus, and, above all, by the need to stress the importance of primary and secondary prevention measures (currently available for women exclusively). The objective of the Consensus Conference was to make evidence-based recommendations that were designed to facilitate the adoption of a standard approach in clinical practice in Italy.

METHODS

The Sponsoring Panel put a series of questions to the members of the Scientific Committee who prepared a summary of the currently available information, relevant for each question, after the review and grading of the existing scientific literature. The summaries were presented to a Jury, also called multidisciplinary Consensus Panel, who drafted a series of recommendations.

RESULTS

The prevalence of HPV in males ranges between 1.3-72.9%;. The prevalence curve in males is much higher than that in females and does not tend to decline with age. Women appear to have a higher probability of acquiring HPV genotypes associated with a high oncogenic risk, whereas in males the probability of acquiring low- or high-risk genotypes is similar. The HPV-related diseases that affect males are anogenital warts and cancers of the penis, anus and oropharynx. The quadrivalent vaccine against HPV has proved to be effective in preventing external genital lesions in males aged 16-26 years in 90.4%; (95%; CI: 69.2-98.1) of cases. It has also proved to be effective in preventing precancerous anal lesions in 77.5%; (95%; CI: 39.6-93.3) of cases in a per-protocol analysis and in 91.7%; (95%; CI: 44.6-99.8) of cases in a post-hoc analysis. Early ecological studies demonstrate reduction of genital warts in vaccinated females and some herd immunity in males when vaccine coverage is high, although males who have sex with males gained no benefit at all. Males with an immunodeficiency disease are at greater risk of developing disease. Infertility seems to be caused by HPV in some cases. Studies demonstrate vaccination to both genders can be more efficacious and social equity matters are to be taken into consideration.

CONCLUSIONS

The Jury made Recommendations based on the scientific evidence presented by the Scientific Committee. Accordingly, for prevention purposes and social fairness and equality, as both sexes are affected by the disease, the vaccination of 12-year-old males against HPV should be recommended in order to guaranty protection to everyone. Aspects related to healthcare policy and economic sustainability, are to be discussed by respective public system representatives. More campaigns to raise awareness through all institutional channels are needed, not only regarding anogenital warts, but for HPV-related diseases in general in males in accordance to new scientific evidences.

Human papillomavirus infection in a male population attending a sexually transmitted infection service

OBJECTIVE

Human Papillomavirus (HPV) infection in men may produce cancer and other major disorders. Men play an important role in the transmission of the virus and act as a reservoir. The aim of this study was to determine the HPV-genotypes and their prevalence in a group of men attending a Sexually Transmitted Infection service. PATIENTS AND SAMPLES: Between July 2002 and June 2011, 1392 balanopreputial, 435 urethral, 123 anal, and 67 condyloma lesions from 1551 men with a mean age of 35.8±11.3 years old (range: 17-87) were collected for HPV-DNA testing.

METHODS

A fragment of the L1-gene and a fragment of the E6/E7-genes were amplified by PCR. Positive samples were typed by hybridization.

RESULTS

The HPV genome was detected in 36.9% (486/1318) balanopreputial and in 24.9% (101/405) urethral (p<0.0001) swabs from 38.1% (538) of 1469 men. Co-infections were present in 5.4% (80/1469) of cases. HPV was found in 43.9% (373/850) of men younger than 35 vs. 31.7% (187/589) of men aged >35. HPV was found in 59.4% (104) of 165 men with lesions (macroscopic or positive peniscopy), and in 22.8% (61/267) without clinical alterations. HPV was also detected in 71.4% (40/56) men with condylomata and in 58.7% (64/109) of men with positive peniscopy.

CONCLUSIONS

HPV prevalence in men was high and decreased with age. HPV was found more frequently in balanopreputial than in urethral swabs. There was a low rate of co-infections. Low-risk HPV vaccine genotypes were the most recurrent especially in younger. Although HPV has been associated with clinical alterations, it was also found in men without any clinical presentation. Inclusion of men in the national HPV vaccination program may reduce their burden of HPV-related disease and reduce transmission of the virus to non-vaccinated women.

Exploring individual HPV coinfections is essential to predict HPV-vaccination impact on genotype distribution: a model-based approach

INTRODUCTION

As for other vaccines that only target a subset of circulating pathogen types, human papillomavirus (HPV) immunization raises the concern of a potential risk of genotype replacement. Potential interactions between HPV types may affect infection acquisition and clearance. However, the existence and the nature of these interactions are still largely unknown. Here, we assess how such interactions might affect the impact of HPV vaccination on genotype distribution in the long term.

METHODS

We develop two mathematical models of the transmission of oncogenic HPV infections that include interactions between vaccine and nonvaccine genotypes to examine the influence of different coinfection dynamics (simultaneous vs. sequential clearance of coinfections) on the evolution of nonvaccine prevalences postimmunization.

RESULTS

After introducing vaccination, the two models give contrasting genotype-replacement outcomes. When hypothesizing that coinfections clear sequentially, genotype replacement depends on whether vaccine and nonvaccine genotypes reduce or favor the acquisition by one or the other. Interestingly, the hypothesis that coinfections clear simultaneously always leads to genotype replacement, even when infections with vaccine types favor the acquisition of infections with nonvaccine types.

CONCLUSION

Our results suggest that predictions regarding HPV genotype replacement strongly depend on the assumptions describing the dynamics (acquisition and clearance) of coinfections. In particular, HPV genotype replacement could be compatible with synergistic interactions between types affecting infections acquisition, contrary to previous suggestions. Understanding better how concurrent infections with multiple types change the acquisition and time to clearance of type-specific infections is essential to be able to predict the impact of vaccination on genotype distribution. Longitudinal data collection in populations, particularly examining infection and coinfection acquisition and clearance, is needed to better predict HPV-vaccine impact.