Transmission of human papillomavirus in heterosexual couples

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.

Naprotecnología: ciencia y persona en la infección por el virus del papiloma humano (VPH) en mujeres y preadolescencentes

En la actualidad hay suficiente evidencia científica que relaciona directamente adquisición, exposición y prevalencia del virus del papiloma humano (VPH) con el cáncer del cuello de uterino. Por ello, el artículo aborda el VPH en la mujer teniendo en cuenta la naprotecnología, que permite conjugar evidencia científica y planteamientos éticos. Se busca que se tengan en cuenta tanto el aspecto biológico de la sexualidad como la capacidad de hacerse persona en su núcleo sexual. De ahí que se analicen programas dirigidos a la educación sexual, basados tanto en la prevención sanitaria como en la antropología de la sexualidad, y apoyados por las instituciones familiares, que han demostrado una mejor acogida ante los riesgos de las enfermedades de transmisión sexual, y entre ellas la infección por el VPH.

Human Papillomavirus and Genital Warts: A Review of the Evidence for the 2015 Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines

To provide updates for the 2015 Centers for Disease Control and Prevention sexually transmitted diseases treatment guidelines on human papillomavirus (HPV) and anogenital warts (AGWs), a review of the literature was conducted in key topic areas: (1) epidemiology and burden of disease; (2) transmission and natural history; (3) diagnosis and management of AGWs; (4) occupational exposure of healthcare workers; (5) anal cancer screening among men who have sex with men (MSM); and (6) HPV vaccine recommendations. Most sexually active persons will have detectable HPV at least once in their lifetime; 14 million persons are infected annually, and 79 million persons have prevalent infection. HPV is transmitted frequently between partners; more frequent transmission has been reported from females to males than from males to females. A new formulation of imiquimod (3.75% cream) is recommended for AGW treatment. Appropriate infection control, including performing laser or electrocautery in ventilated rooms using standard precautions, is recommended to prevent possible transmission to healthcare workers who treat anogenital warts, oral warts, and anogenital intraepithelial neoplasias (eg, cervical intraepithelial neoplasia). Data are insufficient to recommend routine anal cancer screening with anal cytology in persons living with human immunodeficiency virus (HIV)/AIDS or HIV-negative MSM. An annual digital anorectal examination may be useful for early detection of anal cancer in these populations. HPV vaccine is recommended routinely for 11- or 12-year-olds, as well as for young men through age 21 years and young women through age 26 years who have not previously been vaccinated. HPV vaccine is also recommended for MSM, people living with HIV/AIDS, and immunocompromised persons through age 26 years.

Partner Human Papillomavirus Viral Load and Incident Human Papillomavirus Detection in Heterosexual Couples

BACKGROUND

The association between partner human papillomavirus (HPV) viral load and incident HPV detection in heterosexual couples is unknown.

METHODS

HPV genotypes were detected in 632 human immunodeficiency virus (HIV)-negative couples followed for 2 years in a male circumcision trial in Rakai, Uganda, using the Roche HPV Linear Array. This assay detects 37 genotypes and provides a semiquantitative measure of viral load based on the intensity (graded 1-4) of the genotype-specific band; a band intensity of 1 indicates a low genotype-specific HPV load, whereas an intensity of 4 indicates a high load. Using Poisson regression with generalized estimating equations, we measured the association between partner's genotype-specific viral load and detection of that genotype in the HPV-discordant partner 1 year later.

RESULTS

Incident detection of HPV genotypes was 10.6% among men (54 of 508 genotype-specific visit intervals) and 9.0% among women (55 of 611 genotype-specific visit intervals). Use of male partners with a baseline genotype-specific band intensity of 1 as a reference yielded adjusted relative risks (aRRs) of 1.14 (95% confidence interval [CI], .58-2.27]) for incident detection of that genotype among women whose male partner had a baseline band intensity of 2, 1.75 (95% CI, .97-3.17) among those whose partner had an intensity of 3, and 2.52 (95% CI, 1.40-4.54) among those whose partner had an intensity of 4. Use of female partners with a baseline genotype-specific band intensity of 1 as a reference yielded an aRR of 2.83 (95% CI, 1.50-5.33) for incident detection of that genotype among men whose female partner had a baseline band intensity of 4. These associations were similar for high-risk and low-risk genotypes. Male circumcision also was associated with significant reductions in incident HPV detection in men (aRR, 0.53 [95% CI, .30-.95]) and women (aRR, 0.42 [95% CI, .23-.76]).

CONCLUSIONS

In heterosexual couples, the genotype-specific HPV load in one partner is associated with the risk of new detection of that genotype in the other partner. Interventions that reduce the HPV load may reduce the incidence of HPV transmission.

The natural history of genital human papillomavirus among HIV-negative men having sex with men and men having sex with women

BACKGROUND

Although human immunodeficiency virus (HIV)-negative men having sex with men (MSM) bear a substantial burden of human papillomavirus (HPV)-associated disease, prospective studies of genital HPV infection in this population are scarce.

METHODS

HPV genotyping was conducted on genital samples from men (aged 18-70 years) from Brazil, Mexico, or the United States who provided specimens at 6-month intervals for up to 4 years. Eligibility criteria included no history of genital warts or HIV infection. Evaluable specimens were collected from 564 MSM and 3029 men having sex with women (MSW). Incidence and clearance estimates with 95% confidence intervals were calculated.

RESULTS

The 12-month cumulative incidence of genital HPV was high in both MSM (25%; 95% confidence interval, 21%-30%) and MSW (21%; 20%-23%). After stratifying by city, MSM and MSW incidence rates were comparable, with 3 exceptions where MSM had higher incidence in ≥1 city: the group of quadrivalent vaccine types, HPV-45, and HPV-11. Median times to HPV-16 clearance were also comparable, with point estimates of >6 months for both MSM and MSW.

CONCLUSIONS

Unlike with many other sexually transmitted infections, genital HPV natural history may be similar in HIV-negative MSM and MSW. Study periods of ≤6 months, however, may not be long enough to accurately measure the persistence of these infections in men.

The role of monogamy and duration of heterosexual relationships in human papillomavirus transmission

BACKGROUND

 Published data are equivocal about the relative rates of male-to-female and female-to-male human papillomavirus (HPV) transmission. Our objective was to estimate genital HPV incidence among heterosexual partners from a broad age range and to investigate the effects of monogamy and relationship duration on incidence.

METHODS

 HPV genotyping was conducted for heterosexual partners, aged 18-70 years, from Tampa, Florida, who provided genital exfoliated cell specimens at semiannual visits during a 2-year study. The rate of incident HPV detection was assessed for 99 couples, and transmission incidence was estimated among a subset of 65 discordant couples. We also evaluated the effect of monogamy and relationship duration on transmission incidence.

RESULTS

 Couples were followed up for a median of 25 months and had a mean age of 33 years for both sexes. The HPV type-specific transmission incidence rate was 12.3 (95% confidence interval, 7.1-19.6) per 1000 person-months for female-to-male transmission and 7.3 (95% confidence interval, 3.5-13.5) per 1000 person-months for male-to-female transmission. Regardless of monogamy status or relationship duration, there was a similar pattern of increased incident HPV detection among men compared with women.

CONCLUSIONS

 HPV may be transmitted more often from women to men than from men to women, suggesting a need for prevention interventions, such as vaccination, for men.

The association of HPV-16 seropositivity and natural immunity to reinfection: insights from compartmental models

BACKGROUND

Seroreactivity, processes of seroconversion and seroreversion, in the context of HPV infection has been investigated in numerous studies. However, the data resulting from these studies are usually not accounted for in mathematical transmission models of various HPV types due to gaps in our understanding of the nature of seroreactivity and its implications for HPV natural history.

METHODS

In this study we selected a number of simple but plausible compartmental transmission models of HPV-16, differing in assumptions regarding the relation between seropositivity and immunity, and attempted to calibrate them to Australian HPV seroprevalence data for females and males, as well as DNA prevalence data for females, using a Bayesian model comparison procedure. We ranked the models according to both their simplicity and ability to be fitted to the data.

RESULTS

Our results demonstrate that models with seroreversion where seropositivity indicates only a partial or very short-term full protection against re-infection generate age-specific HPV DNA prevalence most consistent with the observed data when compared with other models.

CONCLUSIONS

Models supporting the notion that seropositive individuals are fully immune to reinfection demonstrated consistently inferior fits to the data than other models making no such assumption.

Reevaluation of epidemiological data demonstrates that it is consistent with cross-immunity among human papillomavirus types

BACKGROUND

The degree of cross-immunity between human papillomavirus (HPV) types is fundamental both to the epidemiological dynamics of HPV and to the impact of HPV vaccination. Epidemiological data on HPV infections has been repeatedly interpreted as inconsistent with cross-immunity.

METHODS

We reevaluate the epidemiological data using a model to determine the odds ratios of multiple to single infections expected in the presence or absence of cross-immunity. We simulate a virtual longitudinal survey to determine the effect cross-immunity has on the prevalence of multiple infections. We calibrate our model to epidemiological data and estimate the extent of type replacement following vaccination against specific HPV types.

RESULTS

We find that cross-immunity can produce odds ratios of infection comparable with epidemiological observations. We show that the sample sizes underlying existing surveys have been insufficient to identify even intense cross-immunity. We also find that the removal of HPV type 16, type 18, and types 6 and 11 would increase the prevalence of nontargeted types by 50%, 29%, and 183%, respectively.

CONCLUSIONS

Cross-immunity between HPV types is consistent with epidemiological data, contrary to previous interpretations. Cross-immunity may cause significant type replacement following vaccination, and therefore should be considered in future vaccine studies and epidemiological models.

Updates on human papillomavirus and genital warts and counseling messages from the 2010 Sexually Transmitted Diseases Treatment Guidelines

BACKGROUND

In April 2009, experts on sexually transmitted diseases (STDs) were convened to review updates on STD prevention and treatment in preparation for the revision of the Centers for Disease Control and Prevention (CDC) STD Treatment Guidelines. At this meeting, there was a discussion of important updates on human papillomavirus (HPV), genital warts, and cervical cancer screening.

METHODS

Key questions were identified with assistance from an expert panel, and systematic reviews of the literature were conducted searching the English-language literature of the PubMed computerized database (US National Library of Medicine). The available evidence was reviewed, and new information was incorporated in the 2010 CDC STD Treatment Guidelines.

RESULTS

Two HPV vaccines are now available, the quadrivalent HPV vaccine and the bivalent HPV vaccine; either vaccine is recommended routinely for girls aged 11 or 12 years. The quadrivalent HPV vaccine may be given to boys and men aged 9-26 years. A new patient-applied treatment option for genital warts, sinecatechins 15% ointment, is available and recommended for treatment of external genital warts. This product is a mixture of active ingredients (catechins) from green tea. Finally, updated counseling guidelines and messages about HPV, genital warts, and cervical cancer are included.

CONCLUSIONS

This manuscript highlights updates to the 2010 CDC STD Treatment Guidelines for HPV and genital warts. Important additions to the 2010 STD Treatment Guidelines include information on prophylactic HPV vaccine recommendations, new patient-applied treatment options for genital warts, and counseling messages for patients on HPV, genital warts, cervical cancer screening, and HPV tests.

EcPV2 DNA in equine genital squamous cell carcinomas and normal genital mucosa

Squamous cell carcinoma (SCC) represents the most common genital malignant tumor in horses. Similar to humans, papillomaviruses (PVs) have been proposed as etiological agents and recently Equine papillomavirus type 2 (EcPV2) has been identified in a subset of genital SCCs. The goals of this study were (1) to determine the prevalence of EcPV2 DNA in tissue samples from equine genital SCCs, penile intraepithelial neoplasia (PIN) and penile papillomas, using EcPV2-specific PCR, (2) to examine the prevalence of latent EcPV2 infection in healthy genital mucosa and (3) to determine genetic variability within EcPV2 and to disentangle phylogenetic relationships of EcPV2 among PVs. EcPV2 DNA was detected in all but one penile SCC (15/16), in all PIN lesions (8/8) and penile papillomas (4/4). Additionally, EcPV2 DNA was demonstrated in one of two metastasized lymph nodes, one contact metastasis in the mouth, two vaginal and one anal lesion. In healthy horses, EcPV2 DNA was detected in 10% (4/39) of penile swabs but in none of vulvovaginal swabs (0/20). This study confirms the presence of EcPV2 DNA in equine genital SCCs and shows its involvement in anal lesions, a lymph node and contact metastases. Latent EcPV2 presence was also shown in normal male genital mucosa. We found that different EcPV2 variants cocirculate among horses and that EcPV2 is related to the Delta+Zeta PVs and is only a very distant relative of high-risk human PVs causing genital cancer. Thus, similar viral tropism and similar malignant outcome of the infection do not imply close evolutionary relationship.

Genital transmission of human papillomavirus in recently formed heterosexual couples

We estimated human papillomavirus (HPV) transmission rates among persons with documented sexual exposure to an infected partner. Recently formed couples enrolled in the HITCH Study (HPV Infection and Transmission among Couples through Heterosexual activity) in Montreal, Canada, and provided genital specimens for DNA testing of 36 HPV genotypes. At enrollment, 179 couples were discordant for ≥1 HPV types; transmission was observed at follow-up in 73 partnerships. There was little difference between the male-to-female (3.5 per 100 person-months, 95% confidence interval [CI], 2.7-4.5) and female-to-male (4.0 per 100 person-months, 95% CI, 3.0-5.5) transmission rates. Rates did not vary with the lifetime number of partners reported by the initially uninfected partner, providing no evidence of reduced susceptibility for those with extensive sexual histories. Transmission was also relatively homogeneous across HPV genotypes and alpha species and oncogenic risk categories. The findings contribute to a small but growing evidence base regarding the natural history of HPV transmission.

Epidemiology and burden of HPV infection and related diseases: implications for prevention strategies

Human papillomavirus (HPV) infection is a necessary, although not sufficient cause of cervical cancer. Globally, HPV infection accounts for an estimated 530,000 cervical cancer cases (~270,000 deaths) annually, with the majority (86% of cases, 88% of deaths) occurring in developing countries. Approximately 90% of anal cancers and a smaller subset (<50%) of other cancers (oropharyngeal, penile, vaginal, vulvar) are also attributed to HPV. In total, HPV accounts for 5.2% of the worldwide cancer burden. HPVs 16 and 18 are responsible for 70% of cervical cancer cases and, especially HPV 16, for a large proportion of other cancers. Prophylactic vaccination targeting these genotypes is therefore expected to have a major impact on the burden of cervical cancer as well as that of other HPV-related cancers. Over the past 50 years, organized or opportunistic screening with Papanicolaou (Pap) cytology has led to major reductions in cervical cancer in most developed countries. However, due to lack of resources or inadequate infrastructure, many countries have failed to reduce cervical cancer mortality through screening. HPV DNA testing recently emerged as a likely candidate to replace Pap cytology for primary screening. It is less prone to human error and more sensitive than Pap in detecting high-grade cervical lesions. For countries with national vaccination programs, HPV testing may also serve as a low cost strategy to monitor long term vaccine efficacy. Introduction of well organized vaccination and screening programs should be a priority for all countries. Increased support from donors is needed to support this cause.

The role of HPV in head and neck cancer and review of the HPV vaccine

Recent data demonstrate that human papillomavirus also plays a role in cancers other than ano-genital cancers, specifically head and neck cancers, and non-cancerous conditions such as recurrent respiratory papillomatosis. As more and more information about the role of infection in non-cervical diseases is amassed, additional questions about whether prophylactic human papillomavirus vaccines will effectively prevent these conditions are raised. This article reviews the epidemiology of oral human papillomavirus infection and the role of human papillomavirus in head and neck cancers. In addition, it will review the known clinical indications for human papillomavirus vaccination, and highlight other potential clinical targets for the vaccine that have not yet been demonstrated in clinical trials but for which there is biologic plausibility.

Human papillomavirus concordance in heterosexual couples

PURPOSE

Few studies have examined the relationships between sexual or hygienic behaviors and human papillomavirus (HPV) transmission. Our objectives were to (1) describe HPV concordance between the anogenital, oral, and palmar areas of monogamous heterosexual couples; and (2) determine sexual behaviors, hygienic practices, sexual histories, and subject characteristics associated with HPV anogenital concordance.

METHODS

Couples were recruited from women who developed an incident HPV infection while being enrolled in a longitudinal HPV natural history study that recruited from two family-planning clinics. Men were their monogamous partners of at least 3 months. Samples were tested for HPV-DNA of 37 high- and low-risk genotypes. Questionnaires completed privately assessed health, sexual, hygienic history, and behaviors.

RESULTS

A total of 25 couples enrolled between February 2006 and July 2007; none had received HPV vaccine. The average age was 25 years (SD, 6) for men and 23 years (SD, 3) for women. HPV-84 was the most commonly shared HPV type in the anogenital and palmar areas. HPV-16 was the only shared oral-HPV type. Sixty-eight percent of couples had type-specific anogenital concordance. Receiving finger-anal sex (p = .05), sharing towels (p = .04), longer time since last intercourse (women: p = .03, men: p = .02 men), and men washing their genitals after sex (p = .03) were associated with decreased likelihood of concordance. Persistence of incident HPV types in women was associated with HPV in men (p = .002).

CONCLUSIONS

Our findings show that certain hygienic and sexual behaviors are associated with anogenital concordance between healthy, monogamous, heterosexual couples. Future studies are needed to see whether these detections reflect contamination, transient, or established infections.

Human papillomavirus-related disease in men: not just a women's issue

The most common cause of mortality related to human papillomavirus (HPV) infection is cervical cancer. However, male HPV infection is also an important concern, both for the disease burden in men and for the risk of transmission to women. HPV is associated with a variety of cancers in men, including anal cancer and a subset of penile and oral cancers. The incidence of anal and oral cancers related to HPV is increasing in the general population and is growing even faster among individuals who are immunocompromised because of human immunodeficiency virus (HIV) infection. Penile HPV infection is very common among heterosexual men and remains high throughout a wide range of ages. Likewise, anal HPV infection and anal intraepithelial neoplasia are very common throughout a wide range of ages in both HIV-negative and HIV-positive men who have sex with men. Other HPV-related diseases of clinical importance in men include condylomata acuminata (genital warts) and recurrent respiratory papillomatosis. The quadrivalent HPV vaccine has been shown to be highly efficacious in the prevention of genital warts in women and precancerous lesions of the cervix, vulva, and vagina. In addition, recent interim data have shown that the quadrivalent HPV vaccine is highly effective in reducing external genital lesions in young men. Although the protective efficacy of HPV vaccination in men has not yet been fully established-pending the outcome of public policy discussions and cost-efficacy studies-there may be a strong rationale for vaccinating boys, similar to girls, at an early age when they have had limited or no prior sexual activity.