Lifetime number of partners as the only independent risk factor for human papillomavirus infection: a population-based study

Proteases and HPV-Induced Carcinogenesis

Simple Summary

Human papillomavirus (HPV) infection is a sexually transmitted disease with high prevalence worldwide. Although most HPV infections do not lead to cancer, some HPV types are correlated with the majority of cervical cancers, and with some anogenital and oropharyngeal cancers. Moreover, enzymes known as proteases play an essential role in the pathogenic process in HPV-induced carcinogenesis. This review highlights the role of proteases and recent epidemiological data regarding HPV-dependent carcinogenesis.

Abstract

Persistent infection with Human papillomavirus (HPV) is the main etiologic factor for pre-malignant and malignant cervical lesions. Moreover, HPV is also associated with oropharynx and other anogenital carcinomas. Cancer-causing HPV viruses classified as group 1 carcinogens include 12 HPV types, with HPV 16 and 18 being the most prevalent. High-risk HPVs express two oncoproteins, E6 and E7, the products of which are responsible for the inhibition of p53 and pRB proteins, respectively, in human keratinocytes and cellular immortalization. p53 and pRB are pleiotropic proteins that regulate the activity of several signaling pathways and gene expression. Among the important factors that are augmented in HPV-mediated carcinogenesis, proteases not only control processes involved in cellular carcinogenesis but also control the microenvironment. For instance, genetic polymorphisms of matrix metalloproteinase 1 (MMP-1) are associated with carcinoma invasiveness. Similarly, the serine protease inhibitors hepatocyte growth factor activator inhibitor-1 (HAI-1) and -2 (HAI-2) have been identified as prognostic markers for HPV-dependent cervical carcinomas. This review highlights the most crucial mechanisms involved in HPV-dependent carcinogenesis, and includes a section on the proteolytic cascades that are important for the progression of this disease and their impact on patient health, treatment, and survival.

Etiological Overlap Between Sex Under the Influence and Number of Lifetime Sexual Partners

Drug and alcohol use is associated with risky sexual behavior (RSB). It is unclear whether this association is due to correlated liabilities (e.g., third variables influencing both traits), or whether use of drugs and alcohol during sexual decision making increases RSB. This study addresses this question by fitting a series of biometrical models using over 800 twin pairs assessed in early adulthood (m = 25.21 years). Measures included an index of sex under the influence (e.g., frequency that drugs or alcohol affect sexual decision making), number of lifetime sexual partners, and a general measure of substance use. Analyses suggest the covariance among these measures is explained by both genetic and environmental correlated liabilities. The overlap was not specific to sex under the influence, but was shared with a measure of general substance use. Models testing necessary but not sufficient parameters for direction of causation suggest that sex under the influence is unlikely to cause an increase in RSB; more evidence for reverse causation was found.

Human Papillomavirus Vaccines: An Updated Review

Human papillomavirus (HPV) vaccines, which were introduced in many countries in the past decade, have shown promising results in decreasing HPV infection and related diseases, such as warts and precancerous lesions. In this review, we present the updated information about current HPV vaccines, focusing on vaccine coverage and efficacy. In addition, pan-gender vaccination and current clinical trials are also discussed. Currently, more efforts should be put into increasing the vaccine’s coverage, especially in low- and middle-income countries. Provision of education on HPV and vaccination is one of the most important methods to achieve this. Vaccines that target HPV types not included in current vaccines are the next stage in vaccine development. In the future, all HPV-related cancers, such as head and neck cancer, and anal cancer, should be tracked and evaluated, especially in countries that have introduced pan-gender vaccination programs. Therapeutic vaccines, in combination with other cancer treatments, should continue to be investigated.

Sociodemographic and behavioural correlates of lifetime number of sexual partners: findings from the English Longitudinal Study of Ageing

BACKGROUND

No current data are available on correlates of lifetime sexual partners at older ages. This study aimed to explore correlates of the lifetime number of sexual partners in a sample of older adults.

METHOD

Data were from 3054 men and 3867 women aged ≥50 years participating in the English Longitudinal Study of Ageing. Participants reported their lifetime number of sexual partners and a range of sociodemographic characteristics and health behaviours. Multivariable multinomial logistic regression was used to examine correlates of lifetime number of sexual partners, with analyses performed separately for men and women and weighted for non-response.

RESULTS

Younger age, being separated/divorced or single/never married, being a current or former smoker, and drinking alcohol regularly or frequently were independently associated with a higher number of sexual partners in both men and women. Homosexuality in men and bisexuality in women were also associated with a higher number of sexual partners. White ethnicity, regular moderate and vigorous physical activity, and the absence of limiting long-standing illness were independently associated with a higher number of sexual partners in women only, and being in the highest and lowest quintiles of wealth was independently associated with a higher number of sexual partners in men only.

CONCLUSIONS

A higher lifetime number of sexual partners is associated with a number of sociodemographic and behavioural factors. An understanding of who is more likely to have had more sexual partners may help health practitioners to identify individuals who are at greatest risk of sexually transmitted infection and their associated health complications across the life course.

Frequency and coinfection between genotypes of human papillomavirus in a population of asymptomatic women in northern Peru

Objective

Describe the prevalence of HPV genotypes via PCR and DNA sequencing in 397 women who attended to the gynecological outpatient center in the Hospital Regional Docente de Cajamarca from March to September 2017.

Results

A positive PCR result for HPV was observed in 121 cervical samples. A high-risk genotype was found in 63.6% (77/121) of patients, a probably oncogenic type in 23.1% (28/121) and a low-risk type in 7.4%. Among the high-risk genotypes, HPV-31 was the most common one present in 20% (21/77), followed by HPV-16 in 11.4% (12/77). Coinfections between two or more genotypes were observed in 12 cases.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3644-7) contains supplementary material, which is available to authorized users.

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.

Sexual Behaviors and Sexually Transmitted Infections Among Male Veterans and Nonveterans

Little is known about the sexual health of male veterans. This study used nationally representative data from the 2011 to 2013 National Survey of Family Growth to compare sexual behaviors and history of sexually transmitted infections (STIs) between male veterans and nonveterans. The sample included 3,860 men aged 18 to 44 years who reported ever having sex with a man or woman. The key independent variable was veteran status. Sexual behavior outcomes included ≥6 lifetime female partners, ≥10 lifetime partners of either sex, ≥2 past-year partners of either sex, having past-year partners of both sexes, and condom nonuse at last vaginal sex. STI outcomes included past-year history of chlamydia, gonorrhea, or receiving any STI treatment; lifetime history of herpes, genital warts, or syphilis; and an aggregate measure capturing any reported STI history. Logistic regression models were used to evaluate associations between veteran status and each outcome. In models adjusting for age, race/ethnicity, education, income, and marital status, veterans had significantly greater odds than nonveterans of having ≥6 lifetime female partners (OR = 1.5, 95% CI [1.02, 2.31]). In models adjusting for age and marital status, veterans had significantly greater odds of having partners of both sexes in the past year (OR = 4.8, 95% CI [1.2, 19.8]), and gonorrhea in the past year (OR = 3.2, 95% CI [1.2, 8.5]). Male veterans were thus significantly more likely than nonveterans to have STI risk factors. Health care providers should be aware that male veterans may be at higher risk for STIs and assess veterans’ sexual risk behaviors.

Genetic susceptibility to cervical cancer: role of common polymorphisms in apoptosis-related genes

Cervical cancer is a common malignancy which poses a significant health burden among women, especially those living in the developing countries. Although human papillomavirus (HPV) infection has been unequivocally implicated in the etiopathogenesis of the cancer, it alone is not adequate to contribute to the malignant transformation of cervical cells. Most HPV infections regress spontaneously, and only a small proportion of women have persistent infections which eventually lead to malignancy. This suggests that interplays between HPV infection and other cofactors certainly exist during the process of cervical carcinogenesis, which synergistically contribute to the differential susceptibility of an individual to the malignancy. Undoubtedly, host genetic factors represent a major element involved in such a synergistic interaction, and accumulating evidence suggests that polymorphisms in apoptosis-related genes play an important role in the genetic susceptibility to cervical cancer. This review consolidates the recent literatures on the role of common polymorphisms in apoptosis-related genes in genetic susceptibility to cervical cancer.

Influence of risk-taking health behaviours of adolescents on cervical cancer prevention: a Hungarian survey

An anonymous questionnaire survey was conducted among the Hungarian adolescents to establish their use of tobacco, alcohol and drugs in relation to sexual behaviours, knowledge of human papillomavirus (HPV) and cervical cancer, and beliefs and attitudes towards screening and vaccination. Results indicated that adolescent risk-taking health behaviours correlate with risky sexual behaviours. As risk-taking behaviours do not correlate with a better awareness of the risk associated with HPV infection, it is of crucial importance that HPV/cervical cancer preventing educational programmes shall be sensitive to this 'vulnerable' population and draw the attention of these adolescents to their increased risk of sexually transmitted diseases and undesired pregnancies. Well-designed behavioural change interventions may be effective when in addition to providing adolescents (both men and women) with clear information about the implications of an HPV infection, they also aim to improve safer sex behaviours: consistent condom usage, limiting the number of sex partners, as well as encouraging regular participation in gynaecological screenings and uptake of the HPV vaccine. As this study population demonstrated positive attitudes towards the primary and secondary prevention of cervical cancer, the free HPV vaccination for the 12-13-year-old girls in Autumn 2014 will hopefully increase the currently low uptake of the vaccine in Hungary.

Human papillomavirus-related high-grade squamous intraepithelial lesions of the esophagus, skin, and cervix in an adolescent lung transplant recipient: a case report and literature review

High-risk (carcinogenic) genotype human papillomavirus (HPV) infections can be associated with significant morbidity in the immunocompromised solid organ transplant (SOT) recipient. Immunosuppression-associated persistent infection can predispose to the development of rapidly progressive high-grade squamous intraepithelial lesions (HSIL) in this population. We present a case report of an adolescent bilateral lung transplant recipient who developed HSIL of the esophagus, cervix, and skin secondary to HPV. This review highlights the unique developmental needs of the sexually active adolescent SOT recipient and reviews guidelines for HPV-related screening and education of this population.

Local risk factors in genital human papilloma virus infection in cervical smears

BACKGROUND

Infection with human papilloma virus (HPV) is the main cause of cervical cancer, but the local risk factors have not been sufficiently assessed.

AIM

The study is aimed at determining the prevalence and to evaluate the local risk factors of HPV infection in cervical smears at the Imo State University Teaching Hospital, Orlu, Nigeria.

SUBJECTS AND METHODS

The participants involved 445 randomly selected sexually active women attending the antenatal, postnatal, gynecology and family planning clinics in the Department of Obstetrics and Gynecology of the university between April 2004 and May 2012. A questionnaire assessing various socio-demographic characteristics of the participants was administered. The pap smears of the participants were examined microscopically for evidence of HPV infection. The SPSS version 17.0 (Chicago, Illinois, USA) was used to compute and analyze the results. The results were presented in tables as simple percentages. Tests of significance using the Chi-square and fisher exact tests were applied where appropriate.

RESULTS

The prevalence rate of HPV was 10.3%. The peak age-specific prevalence of 11.7% occurred in the 15-19 years age group. There were significant associations between the occurrence of HPV and multiple sexual partners, coital frequency, multiparity, contraceptive use, marital status, low socio-economic status, abnormal vaginal discharge, irregular menstruation, post-coital and post-menopausal bleeding, (P < 0.05).

CONCLUSION

All sexually active women including teenagers should be screened for cervical HPV infection in an organized systematic program equipped with a good call and recall system. There is, therefore, a need to move emphasis from the current practice of opportunistic screening to a systematic screening of the whole population at risk despite cost implications.

A cross-sectional study to estimate high-risk human papillomavirus prevalence and type distribution in Italian women aged 18-26 years

Background

Pre-vaccination information on HPV type-specific prevalence in target populations is essential for designing and monitoring immunization strategies for cervical cancer (CC) prevention. Data on HPV prevalence in Italy are available for women over the age of 24 years, target of the population-based CC screening programmes; while data of HPV prevalence in younger ages are very limited. The present study enrolled Italian women aged 18–26 years in order to assess the prevalence and distribution of high-risk (HR) HPV types. Risk-factors correlated with HR-HPV positivity were also described.

Methods

A sample of 2,289 women was randomly selected from the resident population lists of ten Local Health Units (LHUs) located in six Italian Regions scattered across the country; both rural and urban LHUs were involved. Women aged between 18 and 26 years and living in the selected LHUs were included in the study; pregnant women and women who did not speak Italian were excluded. A total of 1,102 women met the inclusion criteria and agreed to participate. Participants were offered pap test and Hybrid-Capture 2 (HC2) test for HR-HPV types and genotyping was performed on positive smears.

Results

Out of 1,094 valid samples, 205 (18.7%) were HR-HPV positive. Women with 2–4 (OR_adj = 4.15, 95%CI: 2.56-6.72) and ≥5 lifetime partners (OR_adj = 10.63, 95%CI: 6.16-18.36) and women who have used any contraceptive in the last six months (OR_adj = 1.67, 95%CI: 1.09-2.54) had a higher risk to be infected; women living with their partner had a lower risk (OR_adj = 0.56, 95%CI: 0.34-0.92) to acquire infection than women living with parents/friends/alone. Among HC2 positive women, HPV16 was the most prevalent type (30.9%), followed by 31 (19.6%), 66 (12.9%), 51 (11.3%), 18 (8.8%), 56 (8.8%). Co-infections of HR-HC2 targeted types were found in 20.4% of positive samples. The HR-HPV prevalence in women with abnormal cytology (52.4%) was significantly higher than in women with normal cytology (14.6%); however 33.0% of HR-HPV infected women had an abnormal cytology.

Conclusion

HR-HPV prevalence in Italian women aged 18–26 years was 19%, higher than what detected for older women, by other studies using the same molecular method and laboratory network; this result supports the choice of electing girls before the sexual debut as the primary target of HPV vaccination. The HPV type distribution found in this study may represent a baseline picture; an accurate post-vaccine surveillance is necessary to early detect a possible genotype replacement. The high prevalence of viral types other than vaccine-HPV types supports the necessity to guarantee the progression of CC screening programmes in vaccinated women.

Risk factors for and prevention of human papillomaviruses (HPV), genital warts and cervical cancer

Genital HPV infection is associated with development of cervical cancer, cervical neoplasia, anogenital warts, and other anogenital cancers. A number of reviews have primarily addressed the role of HPV infection in cervical carcinogenesis, and differences in human papillomavirus (HPV) subtypes found in cervical cancer cases by histology and geographical region. This review provides an informative summary of the broad body of literature on the burden of HPV, the risk factors for HPV infection, genital warts and cervical cancer, and preventive measures against these conditions in females. Studies have identified the main risk factors for genital HPV infection in females as follows: acquisition of new male partners; an increasing number of lifetime sexual partners both in females and their male partners; and having non-monogamous male partners. Cervical cancer screening and HPV vaccination are the primary measures currently recommended to prevent cervical cancer. There is also an ongoing debate and conflicting findings on whether male circumcision and condom use protect against HPV infection and subsequent development of HPV-related illnesses in females.

Gender-specific relationships between depressive symptoms, marijuana use, parental communication and risky sexual behavior in adolescence

A large body of research has identified correlates of risky sexual behavior, with depressive symptoms and marijuana use among the most consistent psychosocial predictors of sexual risk. However, substantially less research has examined the relationship between these risk variables and adolescent risky sexual behavior over time as well as the interaction of these individual-level predictors with family-level variables such as parenting factors. Additionally, most studies have been restricted to one index of risky sexual behavior, have not taken into account the complex role of gender, and have not controlled for several of the factors that independently confer risk for risky sexual behavior. Therefore, the current study investigated the association between depressive symptoms and parameters of parenting on marijuana use, number of sexual partners and condom usage measured 9 months later for both boys and girls. Participants were 9th and 10th grade adolescents (N = 1,145; 57.7% female). We found that depressive symptoms may be a gender-specific risk factor for certain indices of risky sexual behavior. For boys only, marijuana use at Time 2 accounted for the variance in the relationship between depressive symptoms at Time 1 and number of partners at Time 2. Additionally, strictness of family rules at Time 1 was associated with the number of partners with whom girls engaged in sex at Time 2, but only among those with lower levels of depressive symptoms at Time 1. Results from the current investigation speak to the utility of examining the complex, gender-specific pathways to sexual risk in adolescents. Findings suggest that treatment of mental health and substance use problems may have important implications in rates of risky sexual behavior and, conceivably, controlling the high rates of serious individual and public health repercussions.

Risk factors for human papillomavirus infection among women in Portugal: the CLEOPATRE Portugal Study

OBJECTIVE

To investigate demographic, socioeconomic, lifestyle, and medical factors that might predispose women to cervical human papillomavirus (HPV) infection.

METHOD

A cross-sectional population-based study was performed. Women aged 18-64 years who attended selected obstetrics and gynecology or sexually transmitted disease (STD) clinics in mainland Portugal between February 2008 and March 2009 were recruited, according to an age-stratified sampling strategy. Liquid-based cytology samples were analyzed centrally for HPV genotype and for cytologic features. Univariate and multivariate logistic regression analyses identified risk factors for HPV infection.

RESULTS

Among the 2326 women evaluated, the crude prevalence of HPV infection was 19.4%. Lifetime number of sexual partners was a strong predictor of HPV infection (odds ratio 5.44 for 5-10 partners versus 1 partner; P<0.001). Other risk factors were young age (particularly among women aged 20-24 years; P<0.001); country of birth other than mainland Portugal (P=0.002); education up to secondary school level (P=0.010); smoking history (≤ 10 years; P=0.004); and any STD in the past 12 months (P=0.052).

CONCLUSION

Data from the present study may aid identification of women at increased risk of HPV infection and target prevention strategies.

TRIAL REGISTRATION

National Commission of Data Protection (CNPD) registration number 5346/2007; Sanofi Pasteur MSD study number HPV-E05.

The combined influence of oral contraceptives and human papillomavirus virus on cutaneous squamous cell carcinoma

The vast majority of cutaneous squamous cell carcinoma (CSCC) will occur in those with fair complexion, tendency to burn, and high ultraviolet radiation (UVR) exposure. Organ transplant recipients also are an important population at great risk for CSCC. An association has been reported between oral contraceptive (OC) use, human papillomavirus virus (HPV) and cervical cancer, and there could be a similar association for CSCC. The cutaneous HPV β-E6 protein, a close cousin of the transformative E6 protein underlying anogenital cancers, has been shown to inhibit apoptosis in response to UVR damage and stimulate morphologic transformation in rodent fibroblast cell lines. Furthermore, OC use has been shown to enhance HPV transcription and may contribute to CSCC risk through this pathway.

Human papillomavirus infection and risk factors in a cohort of Tuscan women aged 18-24: results at recruitment

Background

There is conclusive evidence that human papillomavirus (HPV) infections of the cervix are a necessary cause of cervical cancer. In Italy there are consistent data of HPV prevalence in women aged 25 - 64 years, but there is limited data for younger women. The objective of this on-going 3-year prospective cohort study is to investigate the prevalence, acquisition, clearance and persistence of HPV infections in young Tuscan women and the risk factors correlated with such events.

Methods

One thousand and sixty-six women aged between 18 and 24 years were enrolled and received an initial HPV test. They were asked to return to the clinic over the study period for further tests every 12 months, if their HPV HR result was negative, or every 6 months, if positive. Additionally, women with an HPV positive result were given a cytological examination and if the cytological diagnosis was ASC-US or more severe, only women with HPV HR, were referred for colposcopy.

Results

We present here data for the enrolment phase of the study. At baseline, within the study sample, just under 30% of women were infected by HPV and 19.3% of women were infected with oncogenic types. A relationship was highlighted between HPV infection, number of sexual partners (in particularly in the last 3 years) and the lifetime number of partner's partners. Condom use showed a slight protective effect in univariate analysis but these data were not statistically significant in multivariate analysis. The association between HPV infection and demographic and behavioural variables were tested by crude odds ratio (OR). Multivariate logistic regression was applied to compute the adjusted odds ratios.

Conclusions

The prevalence of oncogenic HPV types was high in young Tuscan women. The 3-year follow-up of this cohort may provide a better understanding of the processes of acquisition, clearance and persistence of infection and the correlated risk factors.

Concurrency, sex partner risk, and high-risk human papillomavirus infection among African American, Asian, and Hispanic women

BACKGROUND

Although the role of concurrent sexual partnerships (i.e., having sexual activity with another partner after a current partnership has been established) has been most strongly associated with the transmission of bacterial sexually transmitted infections, its role in the transmission of viral sexually transmitted infections, specifically human papillomavirus (HPV) is less clear.

METHODS

Analysis of risk behavior data collected from 812 women screened for HPV as part of a sentinel surveillance project conducted in a family planning clinic, a primary care clinic, and 2 sexually transmitted disease clinics in Los Angeles, CA.

RESULTS

The mean age of participants was 34.2 years (range: 18-65), with 31.8% identifying as African American 32.8% as Asian, and 28.4% as Hispanic. The overall prevalence of high-risk HPV (HR-HPV) was 21.7% and was higher among women who reported a concurrent partnership (25.7%) as compared to those who reported no concurrency (17.1%; P = 0.004). In multivariate analysis, concurrency was associated with HR-HPV and this relationship varied by race/ethnicity. Among Hispanic women those reporting a concurrent partnership were nearly twice as likely to have HR-HPV as compared to those who did not report concurrency (adjusted odds ration [AOR] = 1.71; 95% confidence interval [CI]: 1.13-2.58). However, among African American women those who reported a concurrent partnership were less likely to be diagnosed with HR-HPV (AOR = 0.60; 95% CI: 0.37-0.98).

CONCLUSIONS

This study demonstrates that concurrency is associated with HR-HPV and that there may be differences by race/ethnicity in the individual or partnership characteristics of those who report concurrency.

Prevalence of human papillomavirus infection among young women in North India

BACKGROUND

The number of women infected with human papillomavirus (HPV) and the distribution of the HPV genotypes vary across populations and with age.

OBJECTIVE

To determine the prevalence and genotype distribution of HPV in young married women aged 16-24 years.

METHODS

1300 women residing in an urban slum in Delhi donated samples of exfoliated cervical cells that were collected by the Digene((R)) kit and tested for the presence of HPV DNA by two techniques in parallel, i.e., PCR using PGMY consensus primers for all HPV types and the Digene HPV test (Hybrid Capture 2 (HC2) Probe B for high-risk (hr) types. Genotyping was done on all HPV positive samples using the Roche reverse line blot assay.

RESULTS

HPV infection was detected in 91/1300 (7%) samples by PCR and 110/1300 (8.4%) samples by HC2. Genotyping identified 20 high-risk and 11 low-risk types. HPV16 was the commonest high-risk type (3%) followed by HPV52 (1.2%) and HPV51 (0.8%). Among low-risk types, HPV62 was the commonest (0.8%), followed by HPV84 and HPV89 (0.5% each). Multiple infections were found in 3% of the HPV positive samples.

CONCLUSION

A wide spectrum of HPV genotypes is seen in this young population. Knowledge about HPV types prevalent in communities in different regions of India would be useful in devising the optimum strategy for cervical cancer prevention.

Human papillomavirus typing and soluble interleukin-2 receptor levels in female sex workers with a negative cervical smear result

OBJECTIVE

To investigate the association between high-risk human papillomavirus (HPV) types and soluble interleukin-2 receptor (sIL-2R) levels in female sex workers with a negative cervical smear result, and to determine the effectiveness of using sIL-2R levels to screen for high-risk strains of HPV.

METHOD

A negative cervical smear result and a blood sample were obtained from 68 women: 43 female sex workers and 25 women acting as controls. HPV DNA genotyping was performed and sIL-2R levels were assessed.

RESULTS

Female sex workers had significantly higher sIL-2R levels than women in the control group (318.37+/-239.7 vs 114.4+/-56.5 U/mL, respectively P<0.001). In addition, female sex workers with high-risk strains of HPV had significantly higher sIL-2R levels than those who did not have high-risk strains of HPV (736.7+/-251.5 vs 250.5+/-156.1 U/mL, respectively; P=0.001).

CONCLUSION

High sIL-2R levels may be useful in screening for high-risk strains of HPV in female sex workers who have a negative cervical smear result.

Sexual behaviour and HPV infections in 18 to 29 year old women in the pre-vaccine era in the Netherlands

BACKGROUND

Infection with Human Papillomavirus (HPV) is a necessary event in the multi-step process of cervical carcinogenesis. Little is known about the natural history of HPV infection among unscreened young adults. As prophylactic vaccines are being developed to prevent specifically HPV 16 and 18 infections, shifts in prevalence in the post vaccine era may be expected. This study provides a unique opportunity to gather baseline data before changes by nationwide vaccination occur.

METHODS AND PRINCIPAL FINDINGS

This cross-sectional study is part of a large prospective epidemiologic study performed among 2065 unscreened women aged 18 to 29 years. Women returned a self-collected cervico-vaginal specimen and filled out a questionnaire. All HPV DNA-positive samples (by SPF(10) DEIA) were genotyped using the INNO-LiPA HPV genotyping assay. HPV point prevalence in this sample was 19%. Low and high risk HPV prevalence was 9.1% and 11.8%, respectively. A single HPV-type was detected in 14.9% of all women, while multiple types were found in 4.1%. HPV-types 16 (2.8%) and 18 (1.4%) were found concomitantly in only 3 women (0.1%). There was an increase in HPV prevalence till 22 years. Multivariate analysis showed that number of lifetime sexual partners was the most powerful predictor of HPV positivity, followed by type of relationship, frequency of sexual contact, age, and number of sexual partners over the past 6 months.

CONCLUSIONS AND SIGNIFICANCE

This study shows that factors independently associated with HPV prevalence are mainly related to sexual behaviour. Combination of these results with the relative low prevalence of HPV 16 and/or 18 may be promising for expanding the future target group for catch up vaccination. Furthermore, these results provide a basis for research on possible future shifts in HPV genotype prevalence, and enable a better estimate of the effect of HPV 16-18 vaccination on cervical cancer incidence.

Age-specific prevalence of infection with human papillomavirus in females: a global review

PURPOSE

Global data on age-specific prevalence of human papillomavirus (HPV) infection overall, and for high-risk HPV types 16 and 18, are essential for the future implementation of HPV prophylactic vaccines for cervical cancer prevention.

METHODS

A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in women. Studies with clear descriptions of polymerase chain reaction or hybrid capture detection assays were included.

RESULTS

A total of 346,160 women were included in 375 studies. Of 134 studies with age-stratified HPV prevalence data (116 low sexual risk populations, 18 high sexual risk populations), over 50% were from Europe and the Middle East (38%) and North America (19%), with smaller proportions from Asia and Australia (21%), Central and South America (11%), and Africa (10%). Across all geographical regions, data on HPV prevalence were generally limited to women over 18 years of age. Consistently across studies, HPV infection prevalence decreased with increasing age from a peak prevalence in younger women (< or =25 years of age). In middle-aged women (35-50 years), maximum HPV prevalence differed across geographical regions: Africa (approximately 20%), Asia/Australia (approximately 15%), Central and South America (approximately 20%), North America (approximately 20%), Southern Europe/Middle East (approximately 15%), and Northern Europe (approximately 15%). Inconsistent trends in HPV prevalence by age were noted in older women, with a decrease or plateau of HPV prevalence in older ages in most studies, whereas others showed an increase of HPV prevalence in older ages. Similar trends of HPV 16 and/or 18 prevalence by age were noted among 12 populations with available data.

DISCUSSION

Genital HPV infection in women is predominantly acquired in adolescence, and peak prevalence in middle-aged women appears to differ across geographical regions. Worldwide variations in HPV prevalence across age appear to largely reflect differences in sexual behavior across geographical regions. Further studies of HPV prevalence in adolescents are needed for all geographic regions.

Skin reactions to human papillomavirus (HPV) 16 specific antigens intradermally injected in healthy subjects and patients with cervical neoplasia

We have tested the safety and feasibility of a synthetic long peptide-based HPV16-specific skin test to detect cellular immune responses to HPV16 E2, E6 and E7 in vivo. Women with cervical neoplasia (n = 11) and healthy individuals (n = 19) were intradermally challenged with 8 different pools of HPV16 E2, E6 and E7 peptides. The skin test was safe as the injections were perceived as mildly painful and no adverse events were observed. The majority of skin reactions appeared significantly earlier in HPV16+ patients (<8 days) than in healthy subjects (8-25 days). The development of late skin reactions in healthy subjects was associated with the appearance of circulating HPV16-specific T cells and the infiltration of both HPV16-specific CD4+ Th1/Th2 and CD8+ T cells into the skin. These data show that the intradermal injection of pools of HPV16 synthetic long peptides is safe and results in the migration of HPV16-specific T cells into the skin as well as in an increase in the number of circulating HPV16-specific T cells. The use of this test to measure HPV16-specific immunity is currently tested in a low resource setting for the measurement of spontaneously induced T-cell responses as well as in our HPV16 vaccination trials for the detection of vaccine-induced immunity.

[Human papilloma virus-induced disease in HIV-positive patients]

Since the introduction of highly active antiretroviral therapy (HAART), opportunistic infections by bacteria and fungi have been reduced in human immunodeficiency virus (HIV)-positive patients. However, diseases caused by human papilloma virus (HPV) have become more frequent despite HAART. There is an increased incidence of anal and cervical carcinomas, their precancerous lesions such as anal/cervical intraepithelial neoplasia, and condylomas and oral warts. In order to prevent anal carcinomas, HIV-positive patients should receive proctoscopic examinations regularly. The examination should include anoscopy and smears for cytology and HPV polymerase chain reaction.

Prevalence and risk factors of HPV infection among high-risk rural and urban Lithuanian women

AIMS

To investigate the prevalence, persistence and risk factors of high oncogenic risk human papillomavirus (HPV) among urban and rural women of reproductive age coming to consult a gynaecologist.

METHODS

A prospective cohort study in urban (Kaunas) and rural (Marijampole) regions of Lithuania. The data were collected in 8 healthcare institutions from women seeking consultation of gynaecologists using a questionnaire for finding out demographic, social, behavioural and biomedical factors. HPV DNA was determined by molecular hybridization method (hybrid capture version II) determining HPV of high oncogenic risk.

RESULT

1,120 women participated in the study. The prevalence of high-risk HPV among the studied women was 25.1%. It was higher among the urban women than among the rural women. The prevalence of high-risk HPV was increased if the subjects had 2 or more sexual partners during the last 12 months (OR 2.81; 95% CI 1.83-4.32), were 19 years of age or younger (OR 2.68; 95% CI 1.47-4.91), were smoking (OR 1.81; 95% CI 1.16-2.81), and had secondary or lower education level (OR 1.43; 95% CI 1.01-2.04). This infection was obviously associated with high- and low-grade squamous intraepithelial changes of the cervix (OR 1.66, 95% CI = 1.08-2.53).

CONCLUSION

The incidence rate for cervical cancer in Lithuania is one of the highest in comparison with other European countries. HPV infection was also particularly common in the studied population. About one-fourth of the women were infected with high-risk HPV infection. Young and less educated women were found to be the group that was most exposed to HPV, and therefore public health interventions and education seem to be essential in programs aimed at reducing the incidence of cervical cancer.

A population-based study of 18-year old Swedish youths and factors correlated with their total number of lifetime sexual partners

The number of sexual partners has in studies been shown to be a factor correlated with STI but there is little published knowledge on what factors are associated with number of sexual partners.

OBJECTIVES

To examine which variables are correlated with the number of lifetime sexual partners (NLSP) among youths.

STUDY GROUP

All 18-year old girls and boys in four cities in northern Sweden.

METHODS

A population-based study where participants answered a questionnaire regarding their social lifestyle, psychological and sexual health. The associations between these independent variables and the dependent variable (NLSP) were investigated by multivariate linear regression analysis.

RESULTS

The boy and girl median NLSP was 2.0 (P25 =1.0, P75=3.0). The final model explained 29% of the total boy NLSP variation and 46% of the total girl NLSP variation. Eight boy variables and thirteen girl variables significantly correlated with NLSP were found. The two strongest variables associated with increased NLSP among boys and girls, was feelings of guilt or shame after sex and smoking regularly. Variables prior associated with an increased risk of acquiring STI's were associated with increased NLSP. The study found new gender differed behaviour variables correlated to NLSP not previously considered to be risk factors for STI.

CONCLUSIONS

To prevent the spread of STI it is important that persons with many partners are identified, treated if necessary and possible, or encouraged to change their behaviour. The study found several boy and girl variables associated with increased NLSP, which could facilitate both primary- and secondary preventions.

Vaccines for cervical cancer

The review focuses on current and future prevention of invasive cervical cancer (ICC), the second most common cancer among women worldwide. Implementation of population-based cytological screening programmes, using the 'Pap' smear to detect pre-cancerous lesions in the cervix, has resulted in substantial declines in mortality and morbidity from ICC in North America and some European countries. However, cases of, and deaths from, ICC continue to occur. Primary prevention of infection with high-risk human papillomavirus (HPV) types, the central causal factor of ICC, could further reduce incidence of and mortality from ICC. This is particularly the case in developing countries, which bear 80% of the burden of ICC, and where effective Pap screening programmes are extremely difficult to implement. Very promising results from several trials of synthetic HPV type-specific monovalent (HPV 16) and bivalent (HPV 16 and 18) vaccines have recently been published, showing high efficacy against type-specific persistent HPV infection and development of type-specific pre-cancerous lesions. Large-scale phase III trials of a number of such vaccine candidates are currently underway, and there is real hope that an effective vaccine capable of protecting against infection with HPV types 16 and 18 (which together account for approximately 70% of cervical cancer cases worldwide), and thereby of preventing development of a very significant proportion of cases of ICC, could be available within the next 2 years.

Human papillomavirus E6/E7 mRNA expression in women younger than 30 years of age

OBJECTIVE

The prevalence of human papillomavirus (HPV) is high in women younger than 30 years of age, most infections being transient. It is not clear, however, to what extent the E6/E7 transcripts are being expressed. This may be of prognostic importance. In this study, we have determined the prevalence of HPV DNA and mRNA in 283 women younger than 30 years of age.

METHODS

E6/E7 transcripts from HPV types 16, 18, 31, 33 and 45 were detected using PreTect HPV-Proofer, while the presence of HPV DNA was detected using Gp5+/6+ consensus PCR and type-specific PCR.

RESULTS

A total of 92 women (32.5%) were positive by consensus PCR, 59 (20.8%) were positive by type-specific PCR, while 41 (14.5%) were positive by PreTect HPV-Proofer. E6/E7 mRNA expression was detected in 38 (64.4%) of the 59 HPV type-specific DNA positive women. For HPV 16, E6/E7 mRNA expression was observed in 8 (32%) of the 25 DNA positive women. No high-grade lesions were observed in the concomitant cytology.

CONCLUSIONS

Among young women having a normal Pap smear, a high HPV prevalence was found. Hence, use of consensus PCR will most probably give a low prognostic value for identifying subsequent severe dysplasia. The five HPV types 16, 18, 31, 33 and 45 accounted for the majority of infections with two out of three having a detectable E6/E7 mRNA expression. Yet, repeated type-specific testing for HPV mRNA may identify young women with a persistent transforming infection being at increased risk for severe dysplasia.

Colposcopic and histopathologic evaluation of women participating in population-based screening for human papillomavirus deoxyribonucleic acid persistence

OBJECTIVE

Evaluation of colposcopic and histopathological findings in women screened for cervical human papillomavirus deoxyribonucleic acid persistence.

STUDY DESIGN

A total of 12 527 women, aged 32 to 38 years old, attending the population-based cervical cancer screening program in Sweden were randomized 1:1 to mock testing or human papillomavirus deoxyribonucleic acid testing by general primer 5+/6+ polymerase chain reaction and subsequent typing. Human papillomavirus deoxyribonucleic acid-positive women with a normal Papanicolaou smear (n=341) and an equal number from the control group were human papillomavirus tested on average 19 months later. One hundred nineteen women with type-specific human papillomavirus persistence and 111 controls were referred to colposcopy, and 84.8% attended.

RESULTS

Histopathology from colposcopically directed biopsies confirmed cervical intraepithelial neoplasia grade 2 or 3 in 28 of 100 of the women with human papillomavirus deoxyribonucleic acid persistence and in 2 of 95 among controls.

CONCLUSION

Among women with normal Papanicolaou smear attending population-based screening, the positive predictive value of human papillomavirus deoxyribonucleic acid persistence for detection of biopsy-confirmed cervical intraepithelial neoplasia 2 or 3 was 29%.

Human papillomavirus infection: biology, epidemiology, and prevention

Over the past several decades, knowledge of the biology and epidemiology of human papillomavirus (HPV) infection has increased tremendously. However, there are still many unanswered questions concerning the interaction of the virus with its host. The virus has been identified as a necessary causal agent for cervical squamous neoplasia and has been linked to the development of neoplasia in several other mucosal sites. The viral oncogenes E6 and E7 are the major players in the virus' scheme to evade the immune system and use the host cell replication machinery to survive. Many risk factors for infection with HPV have been identified; however, the focus now centers on identifying risk factors for persistence of the infection as it is likely that transient infections play a very small role in the overall development of clinical disease. Prevention measures to date have centered around screening programs, mostly for cervical cancer, including the perfection of screening techniques and inclusion of molecular testing for HPV into screening regimens. The development of prophylactic and therapeutic vaccines has also increased as primary prevention measures appear to have the best hope for long-term effects on cancer incidence.

The epidemiology of human papillomavirus infections

Infection with oncogenic human papillomavirus (HPV) types is a necessary cause of cervical cancer, the second most frequently occurring cancer in women worldwide. Rates of acquisition of HPV are high, particularly among sexually active young adults. Reported estimates of incident HPV infection among initially negative women have reached as high as 60% over a 5-year follow-up period. In this article, we review the epidemiology of HPV infection. In addition to estimates of disease frequency, we highlight risk factors for HPV infection, including the number of lifetime sex partners, which is the most salient risk factor. We discuss significant issues surrounding the natural history of HPV infection, including viral persistence versus clearance, immune response, development of lesions and development of cancer. Finally, we discuss strategies for preventing HPV infection.

Influence of age and geographical origin in the prevalence of high risk human papillomavirus in migrant female sex workers in Spain

OBJECTIVES

To estimate the prevalence and risk factors of high risk human papillomavirus (HPV) infection in migrant female sex workers (FSW) according to age and geographical origin.

METHODS

Cross sectional study of migrant FSW attending a sexually transmitted infection (STI) clinic in Madrid during 2002. Information on sociodemographic characteristics, reproductive and sexual health, smoking, time in commercial sex work, history of STIs, HIV, hepatitis B, hepatitis C, syphilis, and genitourinary infections was collected. High risk HPV Infection was determined through the Digene HPV Test, Hybrid Capture II. Data were analysed through multiple logistic regression.

RESULTS

734 women were studied. Overall HPV prevalence was 39%; 61% in eastern Europeans, 42% in Ecuadorians, 39% in Colombians, 29% in sub-Saharan Africans, and 24% in Caribbeans (p = 0.057). HPV prevalence showed a decreasing trend by age; 49% under 20 years, 35% in 21-25 years,14% over 36 years% (p<0.005). In multivariate analyses, area of origin (p = 0.07), hormonal contraception in women not using condoms (OR 19.45 95% CI: 2.45 to 154.27), smoking, age, and an interaction between these last two variables (p = 0.039) had statistically significant associations with HPV prevalence. STI prevalence was 11% and was not related to age or geographical origin.

CONCLUSIONS

High risk HPV prevalence in migrant FSW is elevated and related to age, area of origin, and use of oral contraceptives in women not using condoms. These data support the role of acquired immunity in the epidemiology of HPV infection and identifies migrant FSW as a priority group for sexual health promotion.

Recent trends in the epidemiology of sexually transmitted infections in the European Union

Sexually transmitted infections (STIs) are a major public health problem in Europe. We review recent trends in the epidemiology of the major acute STIs in the European Union and Norway, their key determinants, and opportunities for enhancing STI prevention interventions in the region.

Dominant human papillomavirus 16 infection in cervical neoplasia in young Japanese women; study of 881 outpatients

OBJECTIVE

Human papillomavirus (HPV) infection is reported to be related to carcinogenesis in the uterine cervix. In Japan, screening for cervical cancer by cytology is performed in women over 30 years old. The purpose of this study was to determine whether there is an association between patient age and cervical neoplasia or HPV infection in Japanese women.

METHODS

Specimens from 881 randomly selected patients who came to our clinic were tested for HPV DNA by using Hybrid Capture II, whereas specimens from a 204-patient randomly selected subset diagnosed with cervical neoplasia were tested for HPV DNA by using polymerase chain reaction (PCR). HPV typing was performed in all the PCR-positive cases.

RESULTS

The HPV-positive rate in the 20- to 29-year-old patients (29.0% in the normal cytology/histology group and 85.5% in the abnormal group) was higher than in the 30- to 59-year-old patients, and the rate declined until age 60 when age increased. While HPV 18, HPV 52, other HPV types, and HPV types as a whole were frequently detected in 30- to 49-year-old patients, HPV 16 was detected more frequently in the younger group than the other HPV types (P = 0.03). Among the HPV 16-positive patients with cervical neoplasia, the proportion of cervical intraepithelial neoplasia (CIN) 3 cases was high (44%) in the 20- to 29-year-old group.

CONCLUSIONS

Screening for cervical neoplasia by cytology should also be performed in women under 30 years old in Japan. The HPV typing could be a tool to strictly follow-up younger women who were diagnosed with CIN.

Using imiquimod for genital warts in female patients

Genital warts (GW) are the manifestation of infection with specific types of human papillomavirus (HPV), one of the most common sexually transmitted viral infections in the world. Genital warts can be either raised (exophytic) or flat. Exophytic genital warts are most commonly secondary to inoculation of the basal epithelium with nononcogenic HPV types 6 and 11, whereas flat warts are usually secondary to potentially oncogenic HPV types 16 and 31. Genital warts can occasionally cause irritation and discomfort, particularly during intercourse, although most cases are asymptomatic. It is the psychosocial effects of infection, such as a sense of shame, depression, and anxiety, that represent the more significant toll for most patients with GW. Current therapies for GW are mainly ablative and do not directly enhance the immune response to HPV. Therefore, recurrence is a problem for many patients. Imiquimod 5% cream is a patient-applied therapy that directly enhances the immune response to HPV and is safe and effective for the treatment of GW. A reduction in viral load is observed following treatment. Low recurrence rates compared to other treatment modalities may be due to the stimulation of the cell-mediated immune response by imiquimod.

Gender differences in sexual biomarkers and behaviors associated with human papillomavirus-16, -18, and -33 seroprevalence

BACKGROUND

The elevated risk for incident head and neck cancer among human papillomavirus (HPV)-16-seropositive individuals has substantiated a role for HPV in the etiology of head and neck cancers. The relationship between HPV seroreactivity and prevalent oral HPV infection in men and women without cancer has yet to be investigated.

GOAL

The goal of this study was to evaluate a possible association between oral HPV infection and HPV seroreactivity after adjustment for gender, sexual behaviors, and sexually transmitted disease.

STUDY DESIGN

A cross-sectional study of factors associated with HPV-16, -18, and -33 seroreactivity was performed in a population of 586 men and women with and without HIV infection. Antibodies in sera were measured by use of a virus-like protein (VLP)-based enzyme-linked immunosorbent assay. Exfoliated cells from the tonsillar and oral mucosa were analyzed for the presence of 38 mucosal HPV types by polymerase chain reaction.

RESULTS

Women had significantly greater seroreactivity for all HPV types investigated when compared with men (odds ratio, 4.3; 95% confidence interval, 3.0-6.0). Seroprevalence was greatest in men and women aged 35 to 45 years. Tonsillar HPV infection, oral sex with men, and HIV infection were independently associated with HPV seroreactivity in men after adjustment for age and number of sexual partners. In women, HSV-2 seropositivity and a history of sexually transmitted diseases were similarly important. Oral and tonsillar HPV infection were not associated with HPV seroreactivity in women.

CONCLUSION

HPV seropositivity is associated with sexually transmitted diseases among women and possibly mucosal HPV exposures in men. Tonsillar HPV infection could impact seroprevalence, particularly in men.

Role of human papillomavirus in penile cancer, penile intraepithelial squamous cell neoplasias and in genital warts

Using PCR, the overall prevalence of human papillomavirus (HPV) DNA in penile carcinoma is about 40-45%, which is similar to the detection rate of HPV-DNA in vulvar carcinoma (50%). In analogy to vulvar cancer two different pathways of penile carcinogenesis seem to exist. In contrast to basaloid and warty penile cancers which are regularly HPV-associated (about 80-100%), only a part of keratinizing and verrucous penile carcinomas appear to be related with HPV (33-35%). Penile intraepithelial neoplasias comprising Bowen's disease, erythroplasia of Queyrat and bowenoid papulosis are precursor lesions of basaloid and warty carcinomas of the penis. Precursors of keratinizing carcinomas and verrucous carcinomas are not established. Whether lichen sclerosus and squamous-cell hyperplasia precede penile keratinizing carcinoma is a matter of discussion. Giant condylomata acuminata may precede the development of verrucous carcinomas in some cases. Since high risk HPVs are more frequently found in verrucous carcinomas than in giant condylomas, HPV typing may be a helpful diagnostic step to differentiate giant condyloma from verrucous carcinoma.

HPV infection and number of lifetime sexual partners are strong predictors for 'natural' regression of CIN 2 and 3

The aim of this paper was to evaluate the factors that predict regression of untreated CIN 2 and 3. A total of 93 patients with colposcopic persistent CIN 2 and 3 lesions after biopsy were followed for 6 months. Human papillomavirus (HPV) types were determined by polymerase chain reaction at enrolment. We analysed the biologic and demographic predictors of natural regression using univariate and multivariate methods. The overall regression rate was 52% (48 out of 93), including 58% (22 out of 38) of CIN 2 and 47% (26 out of 55) of CIN 3 lesions (P=0.31 for difference). Human papillomavirus was detected in 84% (78 out of 93) of patients. In univariate analysis, 80% (12 out of 15) of lesions without HPV regressed compared to 46% (36 out of 78) of lesions with HPV infection (P=0.016). Women without HPV and those who had a resolution of HPV had a four-fold higher chance of regression than those with persistent HPV (relative odds=3.5, 95% CI=1.4-8.6). Women with five or fewer lifetime sexual partners had higher rates of regression than women with more than five partners (P=0.003). In multivariate analysis, HPV status and number of sexual partners remained as significant independent predictors of regression. In conclusion, HPV status and number of lifetime sexual partners were strongly predictive of regression of untreated CIN 2 and 3.

Polymer-based enzyme-linked immunosorbent assay using human papillomavirus type 16 (HPV16) virus-like particles detects HPV16 clade-specific serologic responses

Human papillomavirus type 16 (HPV16) virus-like particles (VLP) were used as antigen in a polymer enzyme-linked immunosorbent assay (ELISA) to measure antibodies to HPV capsid proteins. Serum samples from 575 college women, previously tested for the presence of cervicovaginal HPV DNA, were analyzed. The prevalences of anti-HPV16 VLP antibodies at baseline were 14.1% for immunoglobulin G (IgG) and 6.4% for IgA. The seroprevalences of IgG in women with cervicovaginal HPV16, HPV16-related types, and other HPV types were 55, 33, and 19%, respectively (P < 0.001), compared to the prevalence in women without an HPV infection (10%). HPV VLP IgA seropositivity was associated with high HPV16 VLP IgG optical density values. The seropositivity of IgG antibodies was independently associated with infection with HPV16 or HPV16-related types, increased number of lifetime male partners for vaginal sex, having sex with men >/= 5 years older, history of abnormal PAP smear, older age, and living separately from parents. Use of HPV16 VLP polymer ELISA detects clade-specific responses and suggests an HPV16 VLP vaccine may have broader protection that initially anticipated.

Human papillomavirus infection and use of oral contraceptives

Human papillomavirus (HPV) infection is thought to be a necessary but not sufficient cause of most cases of cervical cancer. Since oral contraceptive use for long durations is associated with an increased risk of cervical cancer, it is important to know whether HPV infection is more common in oral contraceptive users. We present a systematic review of 19 epidemiological studies of the risk of genital HPV infection and oral contraceptive use. There was no evidence for a strong positive or negative association between HPV positivity and ever use or long duration use of oral contraceptives. The limited data available, the presence of heterogeneity between studies and the possibility of bias and confounding mean, however, that these results must be interpreted cautiously. Further studies are needed to confirm these findings and to investigate possible relations between oral contraceptive use and the persistence and detectability of cervical HPV infection.

Human papillomavirus and cervical neoplasia

Cervical cancer accounts for about 10% of all newly diagnosed cancers in women worldwide. The association between HPV infection and cervical neoplasia appears to be stronger than the association between smoking and lung cancer. At least 20 oncogenic HPV types have been identified in > 95% of preinvasive and invasive cervical cancers, HPV type 16 being the most common. HPV detection is important to identify those patients who may be at high risk for the development of cervical neoplasia. Detection techniques include Hybrid Capture (Digene, Silver Springs, MD) and PCR. Viral integration appears to be one of the necessary steps in malignant transformation. Recently, some of the repeated chromosomal alterations and patterns of integration sites have been identified in cervical cancer specimens. The low rate of HPV-negative cancers implies an effective HPV vaccine might have the ability to eradicate cervical cancer worldwide.

The status of HPV16-specific T-cell reactivity in health and disease as a guide to HPV vaccine development

Human papilloma viruses (HPV) are among the most common sexually transmitted pathogens in young adults. In the majority of individuals, anti-viral immunity is capable of suppressing viral infection but in a minority of patients viral infection is not cleared in time to prevent the development of malignancies. In these cases, HPV16-specific immunity may develop too late, is not strong enough, and/or is possibly of the wrong type. The influence of pre-existing immunity on the efficacy of vaccines is largely unknown. Nor has it been studied what the effect is of vaccines on the various types of pre-existing HPV-specific T-cell immunity. Animal models showing that vaccines are able to protect against a subsequent tumor challenge and even to treat transplantable tumors, are not qualified to address this point because tumor development is not preceded by persistent viral infection. Therefore, the comparison between fully characterized pre-existing HPV-specific immunity in patients and healthy subjects is a prerequisite for the full appreciation of vaccine-efficacy as well as for further development of next-generation vaccines.