Condom use and the risk of genital human papillomavirus infection in young women

Human papillomavirus and cervical cancer

Cervical cancer is the second most common cancer in women worldwide, and knowledge regarding its cause and pathogenesis is expanding rapidly. Persistent infection with one of about 15 genotypes of carcinogenic human papillomavirus (HPV) causes almost all cases. There are four major steps in cervical cancer development: infection of metaplastic epithelium at the cervical transformation zone, viral persistence, progression of persistently infected epithelium to cervical precancer, and invasion through the basement membrane of the epithelium. Infection is extremely common in young women in their first decade of sexual activity. Persistent infections and precancer are established, typically within 5-10 years, from less than 10% of new infections. Invasive cancer arises over many years, even decades, in a minority of women with precancer, with a peak or plateau in risk at about 35-55 years of age. Each genotype of HPV acts as an independent infection, with differing carcinogenic risks linked to evolutionary species. Our understanding has led to improved prevention and clinical management strategies, including improved screening tests and vaccines. The new HPV-oriented model of cervical carcinogenesis should gradually replace older morphological models based only on cytology and histology. If applied wisely, HPV-related technology can minimise the incidence of cervical cancer, and the morbidity and mortality it causes, even in low-resource settings.

Human papillomavirus and HPV vaccines: a review

Cervical cancer, the most common cancer affecting women in developing countries, is caused by persistent infection with "high-risk" genotypes of human papillomaviruses (HPV). The most common oncogenic HPV genotypes are 16 and 18, causing approximately 70% of all cervical cancers. Types 6 and 11 do not contribute to the incidence of high-grade dysplasias (precancerous lesions) or cervical cancer, but do cause laryngeal papillomas and most genital warts. HPV is highly transmissible, with peak incidence soon after the onset of sexual activity. A quadrivalent (types 6, 11, 16 and 18) HPV vaccine has recently been licensed in several countries following the determination that it has an acceptable benefit/risk profile. In large phase III trials, the vaccine prevented 100% of moderate and severe precancerous cervical lesions associated with types 16 or 18 among women with no previous infection with these types. A bivalent (types 16 and 18) vaccine has also undergone extensive evaluation and been licensed in at least one country. Both vaccines are prepared from non-infectious, DNA-free virus-like particles produced by recombinant technology and combined with an adjuvant. With three doses administered, they induce high levels of serum antibodies in virtually all vaccinated individuals. In women who have no evidence of past or current infection with the HPV genotypes in the vaccine, both vaccines show > 90% protection against persistent HPV infection for up to 5 years after vaccination, which is the longest reported follow-up so far. Vaccinating at an age before females are exposed to HPV would have the greatest impact. Since HPV vaccines do not eliminate the risk of cervical cancer, cervical screening will still be required to minimize cancer incidence. Tiered pricing for HPV vaccines, innovative financing mechanisms and multidisciplinary partnerships will be essential in order for the vaccines to reach populations in greatest need.

Prophylactic human papillomavirus vaccines: potential for sea change

Persistent human papillomavirus (HPV) infection is the central cause in the development of anogenital warts, precancers and cancers of uterine cervix, and a major factor in the genesis of other malignancies of the lower anogenital and upper aerodigestive tracts. The burden of disease carries very high medical, financial and psychosocial costs. The role of prophylactic HPV vaccines in reducing the burden of disease is discussed in light of the results of multiple randomized, controlled trials conducted worldwide in thousands of young females. The review discusses some of the issues that are still unknown, with respect to long-term vaccine performance, challenges to be overcome to achieve universal, mass prophylactic HPV vaccination, as well as the potential impact of the vaccines on primary screening for, and management of, HPV-related anogenital infection and disease.

Risk factors for genital and anal warts in a prospective cohort of HIV-negative homosexual men: the HIM study

OBJECTIVE

The objective of this study was to determine the prevalence, incidence, and risk factors for genital and anal warts in HIV-negative homosexual men in Sydney.

STUDY DESIGN

The authors conducted a prospective cohort study. Participants were asked whether they had had genital and anal warts at each interview. Details of lifetime sexual contacts and sexual behaviors in the last 6 months were collected.

RESULTS

Among 1,427 men recruited, 8.9% and 19.6% reported a history of genital and anal warts at baseline, respectively. Incidence rates for genital and anal warts were 0.94 and 1.92 per 100 person-years, respectively. In multivariate analysis, both incident genital and anal warts were associated with younger age. In addition, incident genital warts was associated with insertive fingering (P trend = 0.018), whereas incident anal warts was associated with insertive fingering (P trend = 0.007) and insertive fisting (P trend = 0.039).

CONCLUSIONS

Anal warts were twice as common as genital warts. Fingering and other manual sexual practices may be an important transmission route for both.

Assessing the introduction of universal human papillomavirus vaccination for preadolescent girls in The Netherlands

A persistent infection with human papillomavirus (HPV) is a prerequisite for the development of cervical cancer. Clinical trials with HPV-vaccines have been very successful in preventing persistent HPV16/18 infections, the two most oncogenic HPV-genotypes. We assessed the introduction of universal HPV-vaccination for preadolescent girls in the Dutch National Immunization Programme. Long-term vaccine efficacy, the need and extent of a catch-up programme for young women, and the impact of vaccination on the cervical cancer screening programme are major unresolved issues. Preliminary conservative estimates (80% vaccine efficacy and no effects on the screening programme, transmission rate, non-cervical cancer incidence, and cross protection) predict an acceptable cost-effectiveness ratio for universal vaccination of preadolescent girls.

Sexual Health for People Living with HIV

Sexual health is defined in terms of well-being, but is challenged by the social, cultural and economic realities faced by women and men with HIV. A sexual rights approach puts women and men with HIV in charge of their sexual health. Accurate, accessible information to make informed choices and safe, pleasurable sexual relationships possible is best delivered through peer education and health professionals trained in empathetic approaches to sensitive issues. Young people with HIV especially need appropriate sex education and support for dealing with sexuality and self-identity with HIV. Women and men with HIV need condoms, appropriate services for sexually transmitted infections, sexual dysfunction and management of cervical and anogenital cancers. Interventions based on positive prevention, that combine protection of personal health with avoiding HIV/STI transmission to partners, are recommended. HIV counselling following a positive test has increased condom use and decreased coercive sex and outside sexual contacts among discordant couples. HIV treatment and care have reduced stigma and increased uptake of HIV testing and disclosure of positive status to partners. High adherence to antiretroviral therapy and safer sexual behaviour must go hand-in-hand. Sexual health services have worked with peer educators and volunteer groups to reach those at higher risk, such as sex workers. Technological advances in diagnosis of STIs, microbicide development and screening and vaccination for human papillomavirus must be available in developing countries and for those with the highest need globally.

Reversible female contraception: current options and new developments

Uncontrolled fertility results in significant infant and maternal mortality and morbidity. Contraception has the potential to reduce this disease burden. Although a rich array of reversible contraceptive methods exists, the need for more effective and user-friendly methods remains. Access to methods and affordability are major barriers in many parts of the world. However, in other areas, successful utilization is limited by convenience factors or a lack of appreciation of fertility risk. To address these issues, new products that require little user effort have been developed. To encourage correct and consistent use of other methods, noncontraceptive benefits are being popularized and new protocols to initiate contraceptive use immediately are being introduced. This review briefly discusses existing contraceptive methods and new developments that are under investigation.

Human Papillomavirus Infection: The Role of Vaccination in Pediatric Patients

Human papillomavirus (HPV) infection is the most common sexually transmitted infection among adolescents and adults in the United States. Given the prevalence of this infection and its relationship with the development of cervical cancer, HPV vaccine development has been a major public health initiative in the last decade. Despite extensive research in the development of these vaccines, there remain many unanswered questions in academic and public arenas regarding their administration and role in adolescent medicine.

Acceptance of human papillomavirus vaccination among Californian parents of daughters: a representative statewide analysis

PURPOSE

To examine likelihood of parental acceptance of human papillomavirus (HPV) vaccination for young adolescent girls, together with reasons for acceptance and nonacceptance. The ultimate goal of this research is to inform policy decisions and educational planning in this area.

METHODS

A random-digit-dial telephone survey of parents in California households was conducted, yielding 522 parents with an eligible daughter. Cross tabulations and odds ratios were employed to analyze likelihood of vaccination acceptability. Reasons provided for acceptance or nonacceptance were analyzed qualitatively.

RESULTS

Overall, 75% of the sample reported that they would be likely to vaccinate a daughter before age 13 years. Hispanic parents were more likely to accept vaccination than were non-Hispanic parents, whereas African-American and Asian-American parents were less likely. Other subgroups less likely to accept vaccination were identified. Five clusters of reasons by nonaccepting parents emerged: pragmatic concerns about effects on sexual behavior, specific HPV vaccine concerns, moral concerns about sexual behavior, general vaccine concerns, and denial of need. A sixth group of interest comprised those who would vaccinate before age 16 years, but not age 13.

CONCLUSIONS

Consistent with previous studies on this topic, a large majority of California parents endorsed HPV vaccination for daughters by the recommended age. Although important subgroup disparities were found, majorities of all subgroups supported vaccination. This information, together with the identified clusters of cognitive decision factors for nonacceptance, has implications for policy decisions and educational planning in this area. Suggestions for further research on subgroup disparities and on cognitive factors involved in parents' decisions arise from these findings.

Repeat voluntary HIV counseling and testing (VCT), sexual risk behavior and HIV incidence in Rakai, Uganda

We examined the effects of repeat Voluntary HIV counseling and testing (VCT) on sexual risk behaviors and HIV incidence in 6,377 initially HIV-negative subjects enrolled in a prospective STD control for HIV prevention trial in rural Rakai district, southwestern Uganda. Sixty-four percent accepted VCT, and of these, 62.2% were first time acceptors while 37.8% were repeat acceptors. Consistent condom use was 5.8% in repeat acceptors, 6.1% in first time acceptors and 5.1% in non-acceptors. A higher proportion of repeat acceptors (15.9%) reported inconsistent condom use compared to first-time acceptors (12%) and non-acceptors (11.7%). Also, a higher proportion of repeat acceptors (18.1%) reported 2+ sexual partners compared to first-time acceptors (14.1%) and non-acceptors (15%). HIV incidence rates were 1.4/100 py (person-years) in repeat acceptors, 1.6/100 py in first time acceptors and 1.6/100 py in non-acceptors. These data suggest a need for intensive risk-reduction counseling interventions targeting HIV-negative repeat VCT acceptors as a special risk group.

Global control of sexually transmitted infections

Sexually transmitted infections other than HIV are important global health issues. They have, however, been neglected as a public-health priority and control efforts continue to fail. Sexually transmitted infections, by their nature, affect individuals, who are part of partnerships and larger sexual networks, and in turn populations. We propose a framework of individual, partnership, and population levels for examining the effects of sexually transmitted infections and interventions to control them. At the individual level we have a range of effective diagnostic tests, treatments, and vaccines. These options are unavailable or inaccessible in many resource-poor settings, where syndromic management remains the core intervention for individual case management. At the partnership level, partner notification and antenatal syphilis screening have the potential to prevent infection and re-infection. Interventions delivered to whole populations, or groups in whom the risks of infection and onward transmission are very high, have the greatest potential effect. Improvements to the infrastructure of treatment services can reduce the incidence of syphilis and gonorrhoea or urethritis. Strong evidence for the effectiveness of most other interventions on population-level outcomes is, however, scarce. Effective action requires a multifaceted approach including better basic epidemiological and surveillance data, high quality evidence about effectiveness of individual interventions and programmes, better methods to get effective interventions onto the policy agenda, and better advocacy and more commitment to get them implemented properly. We must not allow stigma, prejudice, and moral opposition to obstruct the goals of infectious disease control.

Vacuna frente al virus del papiloma humano: un nuevo reto para el pediatra

Human papillomavirus (HPV) infections are the most common sexually transmitted infections in the world. This infection is a necessary cause of cervical cancer, has been related to other forms of anogenital, airway and digestive cancers, and also causes anogenital warts. The recent advances in HPV prophylactic vaccines and their imminent commercial availability will post a new challenge to pediatricians: the indication and administration of these vaccines for the prevention of HPV infection, and consequently, of cervical cancer and other HPV-related diseases. The present article reviews the essentials of HPV infection, its relationship with cervical cancer, the advances in prophylactic HPV vaccines, and the role of the pediatrician in this context.

How will HPV vaccines affect cervical cancer?

Cancer of the uterine cervix is the second largest cause of cancer deaths in women, and its toll is greatest in populations that lack screening programmes to detect precursor lesions. Persistent infection with 'high risk' genotypes of human papillomavirus (HPV) is necessary, although not sufficient, to cause cervical carcinoma. Therefore, HPV vaccination provides an opportunity to profoundly affect cervical cancer incidence worldwide. A recently licensed HPV subunit vaccine protects women from a high proportion of precursor lesions of cervical carcinoma and most genital warts. Here we examine the ramifications and remaining questions that surround preventive HPV vaccines.

Chapter 6: Epidemiology and transmission dynamics of genital HPV infection

This chapter provides an overview of the epidemiology of human papillomavirus (HPV) infection, with a focus on the dynamics of sexual transmission. We explore concepts related to the spread of sexually transmitted infections, including population prevalence, duration of infectivity, patterns of sexual contacts, and transmissibility, including modifiers of susceptibility and infectivity. HPV prevalence and incidence are high in most studies, particularly amongst young women. There is strong evidence that transmission occurs primarily via sexual activity, most commonly vaginal and anal intercourse. Although the duration of infectivity may be short, current evidence suggests that HPV is highly transmissible. The implications of transmission dynamics for the success of future HPV vaccines are discussed.