Prevalence Of Oncogenic Human Papillomavirus Research Articles

Prevalence of oncogenic human papillomavirus in pregnant adolescents, association with colpocytological changes, risk factors and obstetric outcomes

PurposeThe authors aim to carry out an investigation on the impact of cervical oncogenic Human Papillomavirus (HPV) detection in pregnant adolescents, to clarify the prevalence and risk factors, considering the importance and lack of data on this topic in Brazil. MethodsA cross-sectional study was conducted with adolescents receiving prenatal care in a tertiary hospital in São Paulo, Brazil, with routine Pap smear and oncogenic HPV detection test in the uterine cervix. The authors sought to associate the results of these tests with demographic and obstetric variables. ResultsA total of 303 pregnant adolescents whose mean age was 15.30 ± 1.22 years comprised the study subjects. The frequency of high-risk HPV cervical detection was 50.50%. Multivariate analysis revealed that a large number of partners in their lifetime (OR = 1.27) and having a religion (OR = 2.05) were risk factors for cervical detection of oncogenic HPV, while schooling appeared as a protective factor (OR = 0.85). There was an association between this detection and colpocytological alterations, reaching almost 30% of patients, but without association with obstetric and neonatal outcomes. ConclusionThe prevalence found is one of the highest in Brazil and worldwide. A greater number of partners during their lifetime and having religion were detected as possible factors associated with cervical HPV detection. Detection of cervical HPV-DNA did not influence obstetric and neonatal outcomes. The findings of this study reinforce the need to implement educational measures capable of modifying the incidence of sexually transmitted infections in this population and capable of promoting adherence to HPV vaccination programs.

The efficacy of human papillomavirus vaccination in young Japanese girls: the interim results of the OCEAN study

ABSTRACT Human papillomavirus (HPV) vaccine has been used to prevent chronic HPV infection, which accounts for cervical cancer. Japanese Ministry of Health, Labor and Welfare (MHLW) conducted an HPV vaccination campaign in 2010 and the Obstetrical Gynecological Society of Osaka initiated a multicenter, prospective cohort study in Osaka, Japan – OCEAN (Osaka Clinical resEArch of HPV vacciNe) study – to investigate the oncogenic HPV prevalence and the long-term protection rate of HPV vaccine. A total of 2814 participants were enrolled on their visit for HPV vaccination between 12 and 18 years old. Among them, 102 participants received HPV/Pap co-test as primary cancer screening at the age of 20–21. We compared the prevalence in two groups (the vaccinated and the unvaccinated group). HPV infection ratio was significantly lower in the vaccinated group compared to the unvaccinated (12.9% vs. 19.7%; p = .04). In particular, HPV 16 and 18 were not detected in the vaccinated group, while 4.9% of participants in the unvaccinated group were infected (p = .001), suggesting that vaccination provided effective protection against high-risk types of HPV. The cross-protection effect of HPV vaccines was also observed against HPV 31, 45, and 52. Although HPV vaccines were not contributed to the reduction of cervical intraepithelial neoplasia 1 (CIN) (p = .28), CIN2 or worse was not observed in vaccinated group. Our research showed that at the age of 20–21, HPV vaccine inhibited the infection of high-risk HPV and had impacted on the development to CIN2 or worse in Japan.

Molecular Signature of Human Papillomavirus in Upper Aerodigestive Tract Cancers in Congo-Brazzaville

Introduction: Carcinomas of the upper aerodigestive tract have a tropism on the epidermoid mucosa. HPV infection remains one of the risk factors for this cancer. This work aimed to study the presence of human papillomavirus (HPV) in carcinomas of the VADS.
 Materials and Methods: This was a cross-sectional descriptive and analytical study with retrospective data collection over 7 years. The molecular analysis was conducted in Pointe-Noire using Xpert® HPV technology (GeneXpert, Cepheid). The variables studied were anatomopathological and virological.
 Results: The overall molecular prevalence of oncogenic HPV was 28.1%. HPV-16 and HPV-18/45 were the incriminating genotypes in 88.9% and 11.4% of cases, respectively. A statistically significant association was found between co-infection with HPV-oncogenes in subjects over 40 years of age (P=0.01) and the development of these HPVs in squamous cell carcinomas (p=0.02). Notably, oncogenic HPV was found in the majority of laryngeal carcinomas. 
 Conclusion: In countries with limited resources, the Xpert HPV technology from GéneXpert is a reliable and rapid solution for the virological diagnosis of oncogenic HPV associated with carcinomas of the VADS. HPV-16 remains the most prevalent genotype.

Prevalence of oncogenic human papillomavirus (HPV 16/18) infection, cervical lesions and its associated factors among women aged 21-49 years in Amhara region, Northern Ethiopia.

Human papillomavirus (HPV) infection is considered as the major risk factor for the development of cervical cancer, second most frequent cancer in Ethiopia. However, the magnitude of the problem and the associated factors remain unrevealed in the Amhara region. This study aimed to determine the prevalence of HPV infection and factors contributing to the progression of HPV infection to cervical cancer. Facility-based cross-sectional study design was employed among women aged 21 to 49 years of age who came for routine cervical cancer screening to 4 randomly selected hospitals (2 general and 2 referral) of Amhara region from May to October, 2019. The sample size was calculated by using the single population proportion formula, proportionated to hospitals, and women were recruited consecutively. Socio demographic and clinical data were collected using a pretested questionnaire and detection of HPV infection was done using HPV test (OncoE6TM Cervical Test) specific to HPV16/18 in cervical swabs. Visual inspection with acetic acid (VIA) was used to determine cervical lesions (precancerous and cancerous). Descriptive statistics and bivariate and multivariate logistic regression were used to describe HR-HPV and cervical lesions burden and association between HR-HPV, and cervical lesions and potential risk factors. Among 337 women 21 to 49 years (median age of 35 years ±SD = 7.1 years) of age enrolled in the study, The overall prevalence of oncogenic HPVs (HPV16/18) and the VIA-positivity rate, possible an indicative of cervical lesions, were 7.1% and 13.1%, respectively. Logistic regression analysis showed a significant association between early age of first sexual intercourse (COR = 2.26; 95% CI: 1.0-5.05) and level of education (COR = 0.31; 95% CI: 0.12-0.78) with cervical lesions. Higher odds of HPV positivity (COR = 1.56; 95% CI: 0.59-4.11, p = 0.36) and VIA positivity (COR = 1.39; 95% CI: 0.64-3.00, p = 0.39) were observed among participants who had a history of sexually transmitted illnesses (STIs). There was a relatively low prevalence of oncogenic HPV 16/18 and VIA-positivity in women attending four hospitals in the Amhara Region. Early age sexual contact, high parity, and being uneducated/low level of education were independently associated factors with HR-HPV infection and development of cervical lesions, highlighting the importance of prioritizing the limited HPV testing to those risk groups.

Prevalence of oncogenic Human papillomavirus and genetic diversity in the L1 gene of HPV16 HPV 18 HPV31 and HPV33 found in women from Vojvodina Province Serbia

The main purpose of this paper is to estimate the pre-vaccination prevalence of 12 hrHPV types among 564 women from Vojvodina province (Serbia). The corrected contingency coefficient (Ccorr) was used to estimate the importance of association of examined HPV types and cytological diagnosis. The highest association with the abnormal cytology was observed for HPV 16 (Ccorr = 0.493) in all age groups of participants. The effect of HPV 16 was especially clear within the group of women older than 35 years (Ccorr = 0.691), compared with women younger than 35 (Ccorr = 0.333). The molecular characterization at the level of L1 gene of HPV 16, 18, 31 and 33 variants was for the first time assessed in our region. Nearly all HPV 16 isolates cluster with variant lineage A (96.4%) the remaining isolates clustering with variant lineage D. All of HPV 18 and HPV 33 isolates are clustering within the lineage A while isolates of HPV 31 group with lineages A and C. This contributes to understanding of intrinsic geographical and biological differences of examined HPV types and could be useful for development of cervical cancer screening strategies in Vojvodina (Serbia) and diagnosis of HPV related cervical cancer in general.

The Intersection of HIV, Social Vulnerability, and Reproductive Health: Analysis of Women Living with HIV in Rio de Janeiro, Brazil from 1996 to 2016.

Comprehensive care for sexual and reproductive health (SRH) and social needs for women living with HIV remains limited globally. We aimed to assess trends in baseline sociodemographic, clinical, sexual, and reproductive characteristics among a cohort of HIV-infected women in Rio de Janeiro from 1996 to 2016. Participants were stratified into four time periods based on year of enrollment; we compared cross-sectional data from each period. Of 1361 participants (median age 36), most were black or mixed race (60.1%), unemployed (52.1%), and without secondary education (54%). Adolescent pregnancy was common (51.5%), and 18.3% reported sexual debut at < 15years old. Nearly half (45.2%) had < 5 lifetime sexual partners, yet prior syphilis and oncogenic human papillomavirus prevalence were 10.9% and 43.1%, respectively. Lifetime prevalence of induced abortion was 30.3%, and 16% used no contraceptive method. Future research should explore interactions between social vulnerability, HIV, and poor SRH outcomes and healthcare models to alleviate these disparities.

Age-specific HPV prevalence among 116,052 women in Australia’s renewed cervical screening program: A new tool for monitoring vaccine impact

Australia’s transition to primary human papillomavirus (HPV) based cervical screening, has for the first time, provided a passive mechanism for monitoring the impact of vaccination on infection prevalence among women attending screening. We assessed oncogenic HPV prevalence by single year of age in the first 7 months of the program, using data collected from a large screening laboratory in Victoria, Australia, which is routinely screening using cobas 4800, cobas 6800 and Seegene assays. Among 116,052 primary screening samples from women aged 25–74, 9.25% (95%CI: 9.09–9.42%) had oncogenic HPV detected: 2.14% (95%CI: 2.05–2.22%) were 16/18 positive and 7.12% (95%CI: 6.97–7.27%) were positive for only non-16/18 HPV. Prevalence peaked at age 25–29 then decreased with age, but this was driven by non-16/18 types. HPV16/18 prevalence remained low and flat across ages, contrasting with pre-vaccination epidemiology when HPV16/18 peaked in young women. HPV-based screening can precisely monitor HPV prevalence.

Variation in genital human papillomavirus infection prevalence and vaccination coverage among men and women in the USA.

Human papillomavirus (HPV) is the most common sexually transmitted infection that causes majority of anogenital and oropharyngeal cancers. Prophylactic HPV vaccine is available for the primary prevention of cancer and HPV transmission. Here, we are going to discuss the variation of HPV prevalence, HPV vaccination coverage and potential risk factors of men and women, retrieved from the cross-sectional study of the National Health Nutrition Examination Survey, a representative sample of noninstitutionalized, civilian residents in the USA. The overall penile HPV prevalence in men was 45.2% and the high risk oncogenic HPV prevalence defined by DNA testing was 25.1% that appeared to be widespread among all the age groups, which contrasts the vaginal HPV prevalence of 26.8% in women.

Cervical Infection of Oncogenic Human Papillomavirus (HPV) Types in Beijing, China

ObjectiveThis study was designed to determine the prevalence of oncogenic human papillomavirus (HPV) in cervical infections in Beijing, China, and to investigate the odds ratio (OR) of HPV single and multiple infections in abnormal cytology. MethodsA total of 19,018 specimens from outpatients in the department of obstetric and gynecology were collected. They were detected using high-risk HPV genotyping real-time polymerase chain reaction (PCR) kit and analyzed by ThinPrep cytology test for cervical pathological diagnosis. HPV prevalence, age-specific prevalence, and OR of each type of HPV in abnormal cytology were analyzed. ResultsOverall, 19.1% (3,623/19,018) of the individuals were positive for HPV infection, 14.9% (2,833/19,018) were positive for a single HPV type, and 4.2% (790/19,018) were positive for multiple types. Among the 3,623 HPV-positive individuals, the most predominant HPV types were HPV52 (4.4%, 834/19,018), HPV16 (3.7%, 710/19,018), and HPV58 (3.4%, 644/19,018). The OR of multiple infections and single infection differed significantly among disease severities. The OR of dual infection was higher than that of each of the two single infection types, respectively. ConclusionHPV prevalence in the outpatients was 19.1%, and the most predominant HPV types in the study were HPV52, HPV16, and HPV58. Women with multiple infectionswere more likely to have abnormal cytology.

NHANES 2009-2012 Findings: Association of Sexual Behaviors with Higher Prevalence of Oral Oncogenic Human Papillomavirus Infections in U.S. Men.

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancers is higher and increasing more rapidly among men than women in the United States for unknown reasons. We compared the epidemiology of oral oncogenic HPV infection between men and women ages 14 to 69 years (N = 9,480) within the U.S. National Health and Nutritional Examination Surveys (NHANES) 2009-2012. HPV presence was detected in oral DNA by PCR. Analyses were stratified by gender and used NHANES sample weights. Oral oncogenic HPV prevalence was higher among men than women (6.6% vs. 1.5%, P < 0.001), corresponding to 7.07 million men versus 1.54 million women with prevalent infection at any point in time during 2009-2012. Prevalence increased significantly with age, current smoking, and lifetime number of sexual partners for both genders (adjusted Ptrend < 0.02). However, men had more partners than women (mean = 18 vs. 7, P < 0.001). Although oncogenic HPV prevalence was similar for men and women with 0 to 1 lifetime partners, the male-female difference in prevalence significantly increased with number of lifetime partners (adjusted prevalence differences for none, 1, 2-5, 6-10, 11-20, and 20+ partners = 1.0%, 0.5%, 3.0%, 5.7%, 4.6%, and 9.3%, respectively). Importantly, the per-sexual partner increase in prevalence was significantly stronger among men than among women (adjusted synergy index = 3.3; 95% confidence interval, 1.1-9.7), and this increase plateaued at 25 lifetime partners among men versus 10 partners among women. Our data suggest that the higher burden of oral oncogenic HPV infections and HPV-positive oropharyngeal cancers among men than women arises in part from higher number of lifetime sexual partners and stronger associations with sexual behaviors among men.

Prevalence and concordance of human papillomavirus infection at multiple anatomic sites among HIV-infected women from Chennai, India.

Human papillomavirus (HPV) infection at the cervix, anus and oropharynx has been rarely concurrently estimated among HIV-infected women. Using multiplex polymerase chain reaction testing, we prospectively evaluated HPV genotype distribution across three anatomic sites among 50 eligible HIV-infected women from Chennai, India, who provided biological specimens and answered a sexual behaviour questionnaire. We also assessed clinical and behavioural factors related to HPV prevalence. Oncogenic HPV prevalence was comparable between the anus and cervix at 52.2% and 52.0% and lower at the oropharynx at 13.2%; 78% of women with a cervical HPV infection had the same type in the anus. Newly acquired oncogenic HPV infections were lower at cervix (24%) than anus (35%) at three months. 'Any type' cervical HPV prevalence was higher among women with low education and less than five years since HIV diagnosis. CD4+ count and antiretroviral therapy status were not associated with HPV prevalence at the three anatomic sites; however, enrolment cervical HPV16 prevalence was elevated among women with nadir CD4+ <200 cells/µL and enrolment CD4+ <350 cells/µL. Regular cervical screening is essential in HIV-infected Indian women irrespective of CD4+ count and antiretroviral therapy status. Additional research clarifying the natural history of anal HPV infection is also needed in this population.

Prevalence and viral load of oncogenic human papillomavirus (HPV) in pterygia in multi-ethnic patients in the Malay Peninsula.

The aim of the study was to determine the prevalence of human papillomavirus (HPV) in primary and recurrent pterygia samples collected from different ethnic groups in the equatorial Malay Peninsula. DNA was extracted from 45 specimens of freshly obtained primary and recurrent pterygia from patients and from 11 normal conjunctival swabs from volunteers with no ocular surface lesion as control. The presence of HPV DNA was detected by nested PCR. PCR-positive samples were subjected to DNA sequencing to determine the HPV genotypes. Real-time PCR with HPV16 and HPV18 type-specific TaqMan probes was employed to determine the viral DNA copy number. Of 45 pterygia samples with acceptable DNA quality, 29 (64.4%) were positive for HPV DNA, whereas all the normal conjunctiva swabs were HPV negative. Type 18 was the most prevalent (41.4% of positive samples) genotype followed by type 16 (27.6%). There was one case each of the less common HPV58 and HPV59. Seven of the samples harboured mixed infections of both HPV16 and HPV18. All the four known recurrent pterygia samples were HPV-positive, whereas the sole early-stage pterygium sample in the study was HPV-negative. There was no significant association between HPV-positive status with gender or age. A high proportion of patients from the Indian ethnic group (five of six) were HPV-positive, whereas the Malay patients were found to have higher HPV positivity than the Chinese. The viral load of HPV18 samples ranged between 2 × 10(2) and 3 × 10(4) copies per μg, whereas the viral load of HPV16 specimen was 4 × 10(1) to 10(2) copies per μg. This report describes for the first time the quantitative measurement of HPV viral DNA for pterygium samples. The high prevalence of oncogenic HPVs in our samples suggests a possible role for HPV in the pathogenesis of pterygia. Moreover, the relatively low HPV viral load is concordant with the premalignant nature of this ocular condition.

Human Papillomavirus Infection and Cervical Neoplasia among Migrant Women Living in Italy

Human papillomavirus (HPV) infection is highly prevalent in women migrating from countries where cervical screening is not implemented. The variety of HPV genotypes, their prevalence and the association with cervical abnormalities has been investigated by several groups in women moving mainly from Eastern Europe, Africa, and Southern Asia to Italy. All studies are concordant on the elevated rate of HPV infection among immigrants, which is four times higher than that observed among age-matched Italian women. The HPV prevalence among short-term migrants and characterization of viral variants showed that the high prevalence of HPV reflects either individual lifestyle or high prevalence of HPV in the country of origin. The high burden of HPV infection correlates very well with the high incidence of cervical cancer in migrant women. In fact, during the years 2000–2004 the cervical cancer incidence in women from Central and Eastern Europe and living in Central Italy was 38.3 per 100,000, which is statistically significant higher than that of native Italian women (6 per 100,000). In this study, we pooled together the results of three independent studies originally designed to assess the distribution and the prevalence of HPV genotypes among 499 immigrant women living in Southern Italy. A total of 39 mucosal HPV genotypes were identified. The 12 genotypes (HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59) classified as carcinogenic to humans (group 1) accounted for >80% of all infections. HPV16 was the most common viral type in all groups with frequency rates ranging from 15.4% in Africa to 51.1% in Eastern and Southern European HPV-positive women. The high prevalence of oncogenic HPVs and cervical cancer risk among migrant women, together with the lower participation in screening programs, demands for an urgent implementation of preventive strategies to increase screening and vaccine coverage and viral monitoring of uncommon HPV genotypes potential spreading in settled population.

Anal Human Papillomavirus Infection Among HIV-Infected and Uninfected Men Who Have Sex With Men in Beijing, China

In light of China's unique ethnic and sociocultural context, and a marked rise in HIV prevalence among MSM, it is important to determine prevalence, genotypes and predictors of anal human papillomavirus (HPV) among HIV-infected and uninfected men who have sex with men (MSM) in Beijing, China. In 2010-2011, we recruited MSM (age range 18-61; median 28 years) through peer volunteers, and collected demographic/behavioral information via interviewer-administrated questionnaires. Trained health workers collected anal swabs for HPV genotyping by PCR and blood samples for HIV/syphilis serologies. We obtained anal specimens from 212 HIV-infected and 459 HIV-uninfected participants. Among HIV-infected MSM, 82.1% were HPV-infected vs. 57.5% in HIV-uninfected (p<0.01). HIV-infected men had the greatest likelihood of multiple types: 17.9% uninfected; 36.3% with one type; 36.8% with 2-3; 9.0% with ≥4. Oncogenic HPV prevalence was higher among HIV- infected (61.3%) than uninfected participants (39.7%; p<0.01). HIV-uninfected MSM reporting always using condoms during insertive anal intercourse (past 6 months) were less likely to be HPV-infected (OR=0.49, 95%CI: 0.31-0.77). Among HIV-uninfected MSM, HPV infection was associated with unprotected receptive anal intercourse (past 6 months; OR=1.92, 95%CI: 1.19-3.11) and being forced to have sex (previous year; OR=3.32, 95%CI: 1.10-10.0). Multivariable logistic analysis among HIV infected MSM suggested that unprotected oral intercourse (past 6 months) was associated with HPV (adjusted OR=2.12, 95%CI: 1.00-4.48). Syphilis occurred in 55.8% of HIV-infected/HPV-infected, 50.0% of HIV-infected/HPV-uninfected, 19.6% of HIV-uninfected/HPV-infected, and 13.0% of HIV-uninfected/HPV-uninfected MSM. HPV anal infections were more common among HIV-infected than uninfected MSM in China, including oncogenic and multiple types. Unprotected oral and receptive anal sex were was independently associated with HPV infection. Promotion of safer sex and HPV vaccination is strongly recommended among MSM.

A qualitative analysis of factors influencing HPV vaccine uptake in Soweto, South Africa among adolescents and their caregivers.

BackgroundIn South Africa, the prevalence of oncogenic Human Papillomavirus (HPV) may be as high as 64%, and cervical cancer is the leading cause of cancer-related death among women. The development of efficacious prophylactic vaccines has provided an opportunity for primary prevention. Given the importance of psycho-social forces in vaccine uptake, we sought to elucidate factors influencing HPV vaccination among a sample of low-income South African adolescents receiving the vaccine for the first time in Soweto.MethodsThe HPV vaccine was introduced to adolescents in low-income townships throughout South Africa as part of a nationwide trial to understand adolescent involvement in future vaccine research targeting human immunodeficiency virus (HIV). We performed in-depth semi-structured interviews with purposively-sampled adolescents and their care providers to understand what forces shaped HPV vaccine uptake. Interviews were recorded, transcribed, translated, and examined using thematic analysis.ResultsOf 224 adolescents recruited, 201 initiated the vaccine; 192 (95.5%) received a second immunization; and 164 (81.6%) completed three doses. In our qualitative study of 39 adolescent-caregiver dyads, we found that factors driving vaccine uptake reflected a socio-cultural backdrop of high HIV endemnicity, sexual violence, poverty, and an abundance of female-headed households. Adolescents exercised a high level of autonomy and often initiated decision-making. Healthcare providers and peers provided support and guidance that was absent at home. The impact of the HIV epidemic on decision-making was substantial, leading participants to mistakenly conflate HPV and HIV.ConclusionsIn a setting of perceived rampant sexual violence and epidemic levels of HIV, adolescents and caregivers sought to decrease harm by seeking a vaccine targeting a sexually transmitted infection (STI). Despite careful consenting, there was confusion regarding the vaccine’s target. Future interventions promoting STI vaccines will need to provide substantial information for participants, particularly adolescents who may exercise a significant level of autonomy in decision-making.

Oncogenic human papillomavirus-associated nasopharyngeal carcinoma: an observational study of correlation with ethnicity, histological subtype and outcome in a UK population

BackgroundNasopharyngeal carcinoma (NPC) accounts for 0.6% of all cancers worldwide with the highest prevalence in South East Asia, Southern China and Northern Africa but the disease is uncommon in Europe with an annual incidence in this region of less than 1 per 100 000. Although the Epstein-Barr virus (EBV) is a well known causative agent in NPC, recent reports have implicated oncogenic Human Papillomavirus (HPV) in a subgroup of these tumours. The recent striking rise of oropharyngeal carcinoma has been attributed to HPV, but little is known about the prevalence and clinical significance of the virus in NPC. The aim of this study was to determine the prevalence of oncogenic HPV in NPC from tissue archives of two head and neck cancer centres in the UK.MethodsSamples were available for 67 patients with clinically validated NPC. The detection of high-risk HPV was carried out by screening all cases for p16 using immunohistochemistry and HPV DNA by polymerase chain reaction (PCR) using GP5+/6+ primers. All cases with p16 over-expression or positive for HPV by PCR were then examined by high-risk HPV DNA in-situ hybridisation and genotype analysis by PCR.ResultsEleven cases (11/67, 16.4%) showed concurrent over-expression of p16 and evidence of high-risk HPV DNA by in-situ hybridisation; the majority were HPV16 positive. Of these 11 cases, nine occurred in Whites and two in Blacks. Histologically, there were two keratinising squamous cell carcinoma and nine non-keratinising carcinomas (eight differentiated and one undifferentiated). None of the HPV-positive cases showed any co-infection with EBV. There was no statistically significant difference in overall survival outcome between patients with HPV-positive and HPV-negative NPC.ConclusionThe results of this study show that oncogenic HPV is associated with a subgroup of NPCs and is more likely to occur in Whites. However, unlike oropharyngeal carcinoma there was no significant difference in overall survival between patients with HPV-positive and HPV-negative NPC.

Clinical trials of human papillomavirus vaccines and beyond

Human papillomavirus (HPV) is the most common sexually transmitted infectious agent; its 14 oncogenic types are causally associated with 5-10% of all cancers. The major structural HPV protein self-assembles into immunogenic virus-like particles. Two licensed HPV vaccines--the bivalent vaccine comprising HPV types 16 and 18, and the quadrivalent vaccine comprising HPV types 6, 11, 16 and 18--have proven to be safe and efficacious against 6-month-persistent cervical infections of HPV16 and HPV18 and associated precancerous lesions, and both have efficacies of 90-100%. Among baseline HPV-negative adolescent females, vaccine efficacies against the immediate precursor of cervical cancer (intraepithelial neoplasia grade 3) irrespective of HPV type are 93.2% and 43.0% for the bivalent and quadrivalent vaccines, respectively. The quadrivalent vaccine is efficacious (>75% vaccine efficacy) against any of the more-severe precursors of vulval, vaginal and anal cancers. A strong increase in vaccine efficacy with increasing severity of the precancerous lesion is explained by accumulation of the most-oncogenic HPV types 16 and 18 in these lesions. Therefore, prophylactic HPV vaccination will exceed the best results from screening for cancer. With the extremely efficacious prophylactic HPV vaccines, the focus of organized intervention (vaccination and screening) programmes should, however, shift from reducing the HPV disease burden to controlling the prevalence of oncogenic HPV (and nononcogenic HPV) types. Eradication of the major oncogenic HPV types should be pursued.

Human Papillomavirus in Older Women: New Infection or Reactivation?

Human Papillomavirus in Older Women: New Infection or Reactivation?

Investigating a cluster of vulvar cancer in young women: a cross-sectional study of genital human papillomavirus prevalence

BackgroundVulvar cancer is a relatively rare malignancy, which occurs most often in postmenopausal women. We have previously identified a geographic cluster of vulvar cancer in young Indigenous women living in remote communities in the Arnhem Land region of Australia. In this population, we investigated the prevalence of oncogenic human papillomavirus (HPV) infection in anogenital samples (vulvar/vaginal/perianal area and cervix) and compared the overall, type-specific and multiple infection prevalence between sites.MethodsA cross-sectional survey of 551 Indigenous women aged 18–60 years was undertaken in 9 Arnhem Land communities. Women were consented for HPV detection and genotyping collected by a combined vulvar/vaginal/perianal (VVP) sweep swab and a separate PreservCyt endocervical sample collected during Pap cytology screening. HPV DNA testing was undertaken using PCR with broad spectrum L1 consensus PGMY09/11 primers with genotyping of positive samples by Roche Linear Array. The primary outcomes were the prevalence of cervical and VVP high-risk (HR) HPV.ResultsThe prevalence of VVP HR-HPV was 39%, which was significantly higher than the cervical HR-HPV prevalence (26%, p<0.0001). HPV-16 was the most common genotype detected in both sites (VVP 11%, cervical 6%). HPV-16 infection peaked in women aged <20 years; however, there was a marked decline in cervical HPV-16 prevalence with age (p=0.007), whereas following an initial decline, the prevalence of VVP HPV-16 remained constant in subsequent age-groups (p=0.835).ConclusionsIn this population experiencing a cluster of vulvar cancer, the prevalence of cervical oncogenic HPV infection was similar to that reported by studies of other Australian women; however there was a significantly higher prevalence of vulvar/vaginal/perianal infection to cervical. The large discrepancy in HPV prevalence between anogenital sites in this population may represent more persistent infection at the vulva. This needs further investigation, including the presence of possible environmental and/or genetic factors that may impair host immunity.

A revision of sexual mixing matrices in models of sexually transmitted infection

Two sexual mixing matrices previously used in models of sexually transmitted infections (STIs) are intended to calculate the probability of sexual interaction between age groups and sexual behaviour subgroups. When these matrices are used to specify multiple criteria for how people select sexual partners (such as age group and sexual behaviour class), their conditional probability structure means that they have in practice been prone to misuse. We constructed revised mixing matrices that incorporate a corrected conditional probability structure and then used one of them to examine the effect of this revision on population modelling of STIs. Using a dynamic model of human papillomavirus (HPV) transmission as an example, we examined changes to estimates of HPV prevalence and the relative reduction in age-standardised HPV incidence after the commencement of publicly funded HPV vaccination in Australia. When all other model specifications were left unchanged, the revised mixing matrix initially led to estimates of age-specific oncogenic HPV prevalence that were up to 11% higher than our previous models at certain ages. After re-calibrating the model by modifying unobservable parameters characterising HPV natural history, the revised mixing matrix yielded similar estimates to our previous models, predicting that vaccination would lead to relative HPV incidence reductions of 43% and 85% by 2010 and 2050, respectively, compared with 43% and 86% using the unrevised mixing matrix formulation. Our revised mixing matrix offers a rigorous alternative to commonly used mixing matrices, which can be used to reliably and explicitly accommodate conditional probabilities, with appropriate re-calibration of unobservable model parameters.