Characteristic of persistent human papillomavirus infection in women worldwide: a meta-analysis

Objectives

We aimed to estimate the genotype distribution of persistent human papillomavirus (HPV) infection in females worldwide, and provided a scientific basis for the prevention strategies of cervical cancer (CC) and the development of HPV vaccines.

Methods

Both English and Chinese databases were researched from the inception to July 2023. The pooled persistent HPV infection prevalence was calculated using a random effects model. The subgroup analysis was performed to explore the heterogeneity. Publication bias was evaluated using funnel plot, Egger's and Begg's test.

Results

Twenty-eight studies with 27,335 participants were included. The pooled prevalence of persistent HPV infection was 29.37% (95% CI [24.05%∼35.31%]), and the genotypes with the persistent infection prevalence were HPV16 (35.01%), HPV52 (28.19%), HPV58 (27.06%), HPV18 (25.99%), HPV33 (24.37%), HPV31 (23.35%), HPV59 (21.87%), HPV39 (19.54%), HPV68 (16.61%) and HPV45 (15.05%). The prevalence of multiple and single HPV persistent infection were 48.66% and 36.71%, respectively; the prevalence of persistent HPV infection in different age groups (<30, 30∼39, 40∼49, >50) were 29.83%, 28.39%, 22.24% and 30.22%, respectively. The follow-up time was significantly associated with heterogeneity by subgroup analysis (P < 0.05), and the prevalence of persistent infection decreased with longer follow-up time.

Conclusions

Multiple infections were more likely to occur persistent HPV infection than single infection. In addition to HPV vaccination, we should emphasize the follow-up management for women under 30 and over 50 years old, those with high-risk HPV infection (HPV59, 39, 68) and multiple infections.

Collagen-Based Ovule Therapy Reduces Inflammation and Improve Cervical Epithelialization in Patients with Fungal, Viral, and Bacterial Cervico-Vaginitis

Background and Objectives: Vulvovaginal infections pose significant health challenges for women, necessitating effective treatment approaches. This retrospective observational study aimed at investigating the efficacy of collagen-based vaginal ovules therapy, specifically Plurigin Ovules, in restoring cervical epithelialization and reducing inflammation in mycotic, viral, and bacterial cervico-vaginitis. Materials and Methods: A total of 398 women with cervico-vaginitis were included in the study, categorized into three groups: bacterial cervico-vaginitis (Group A), viral cervico-vaginitis (Group B), and fungal cervico-vaginitis (Group C). Participants received vaginal therapy with Plurigin Ovules for three months. Vaginal health parameters were assessed at baseline (T0) and after six months (T1) using various diagnostic tests and analyzed with appropriate statistical tests. Results: Significant improvement in cervico-vaginitis was observed in all three groups. At T1, 87.7% patients of Group A, 66.7% of Group B, and 71.5% of Group C achieved infection resolution (all p < 0.05). Positive colposcopy results decreased across all groups (p < 0.001). Positive vaginal swabs and altered vaginal pH decreased in group A and C (p < 0.001). Positive HPV tests decreased in Group B (p < 0.001). Positive Pap tests and clinical examinations decreased significantly across all groups (p < 0.001). The odds ratios were calculated to reveal the significant associations between these diagnostic outcomes. The therapy was well-tolerated, and no major adverse events were reported. Conclusion: Plurigin Ovules exhibited promising therapeutic outcomes in the three cervico-vaginitis conditions studied. Bacterial cervico-vaginitis showed the most significant improvement, followed by fungal and viral cervico-vaginitis. These findings emphasize the potential of Plurigin Ovules as an effective therapeutic option for cervico-vaginal inflammation and infection, highlighting its role in promoting re-epithelialization and reducing inflammatory processes in the cervix and vagina.

Role of human papillomavirus status after conization for high-grade cervical intraepithelial neoplasia

Human papillomavirus (HPV) is the well‐established etiologic factor for cervical neoplasia. Cervical conization constitutes an effective treatment for high‐grade cervical intraepithelial neoplasia (HG‐CIN). We conducted an observational study for long‐term outcomes and HPV genotype changes after conization for HG‐CIN. Between 2008 and 2014, patients with newly diagnosed HG‐CIN before conization (surveillance new [SN] group) and those who had undergone conization without hysterectomy (surveillance previous [SP] group) were enrolled. HPV testing and Pap smear were performed periodically for the SN and SP (collectively S) groups. All other patients receiving conization for HG‐CIN during the study period were identified from our hospital database. Those eligible but not enrolled into our study were assigned to the non‐surveillance (non‐S) group. For the S group (n = 493), the median follow‐up period was 74.3 months. Eighty‐four cases had recurrent CIN Grade 2 or worse (CIN2+) (5‐year cumulative rate: 14.8%), of which six had invasive cancer. Among the 84 patients, 65 (77.4%) exhibited type‐specific persistence in the paired HPV results, whereas only 7 (8.3%) harbored new HPV types that belonged to the 9‐valent vaccine types. Among the 7397 non‐S patients, 789 demonstrated recurrent CIN2+, of which 57 had invasive cancer. The stages distribution of those progressed to invasive cancer in the non‐S group were more advanced than the S group (P = .033). Active surveillance might reduce the severity of those progressed to cancer. Because a majority of the patients with recurrent CIN2+ had persistent type‐specific HPV infections, effective therapeutic vaccines are an unmet medical need.

What's new?

High‐grade cervical intraepithelial neoplasia (HG‐CIN), a cervical carcinoma precursor, frequently is caused by high‐risk human papillomavirus (hr‐HPV) infection. HG‐CIN can be treated by cervical conization, though the procedure does not eradicate hr‐HPV, potentially enabling CIN recurrence. Here, in Taiwanese patients, investigation of HPV genotype changes in relation to HG‐CIN status after conization shows that 77.4 percent of patients with recurrent CIN 2 grade or worse (CIN2+) after conization had persistent type‐specific HPV infections. Vaccination against the remaining high‐risk HPVs prevented recurrent CIN2+ in only 8.3 percent of patients, revealing an unmet need for effective therapeutic vaccines.

Risk of cervical lesions in high-risk HPV positive women with normal cytology: a retrospective single-center study in China

Background

To investigate high-risk HPV (hr-HPV) genotype distributions and the association between hr-HPV infection with severity of the cervical lesions in women with normal cytology.

Methods

In this cross-sectional study, the result of the hr-HPV test and biopsy of colposcopy of women with normal cytology from January 2012 to January 2019 were analyzed. The detection rate of high-grade squamous intraepithelial lesion (HSIL) and cervical cancer were calculated among different hr-HPV genotypes, viral load group, and age groups.

Results

Five thousand eight hundred eighty women were enrolled in this study. Overall, 59.97% had normal histological results, 19.32% had HSIL, and 1.07% had cervical cancer. The detection rate of HSIL or worse (HSIL+) in women with single HPV16(34.00%), HPV31(27.50%), HPV33(25.58%), and HPV52(20.88%) infection were higher significantly than single HPV18 (15.59%) infection, respectively. The HSIL+ detection rate between HPV16 single infection and multiple infections (excluding HPV18) was no significant difference (34% vs 35.47%, P = 0.638), contrary to HPV18(12.59% vs 21.67%, P = 0.022). In women without HPV16/18 infections, HSIL+ detection rates for single, double, and triple or more hr-HPV infections were 12.28, 20.31, and 37.50%, the risk of detection of HSIL+ significantly increasing. With the hr-HPV DNA load increases, the risk of detection of HSIL+ (χ2 = 91.01, P < 0.0001) and invasive cervical cancer (χ2 = 5.757, P = 0.016) increase. In age < 30, 31–40, 41–50, 51–60, > 60 group, HSIL+ detection rate were 24.80%、22.10%、19.59%、14.29, and 12.61%, respectively.

Conclusion

Women who have normal cytology with HPV 16/18/31/33/52/58 infections, multiple HPV infections and high viral load, have a higher detection rate of HSIL+.

Screening for persistent high-risk HPV infections may be a valuable screening method for young women; A retrospective cohort study

Introduction

Screening of young women is often discouraged because of the high risk of unnecessary diagnostics or overtreatment. Multiple countries therefore use cytology instead of high risk human papillomavirus (hrHPV)-testing as screening method for young women because of the limited specificity of hrHPV-testing. The objective of this study was to investigate how hrHPV screening before the age of 30, can be used to reduce the future prevalence of high-grade cervical lesions in young women.

Methods

We retrospectively analyzed follow-up data from a cohort study on HPV prevalence in unscreened Dutch women aged 18–29 years. Women performed multiple self-collected cervico-vaginal samples for HPV detection and genotyping. At least one valid cervical pathology result was obtained from 1,018 women. Women were categorized as hrHPV negative, cleared- or persistent hrHPV infection. Anonymized follow-up data for each group was obtained. Composite outcome measures were defined as; normal, low-grade squamous intraepithelial lesion (LSIL) or high-grade squamous intraepithelial lesion (HSIL). The association between prior hrHPV status and cytology and histology outcome was analyzed.

Results

After exclusion, a pathology result was registered for 962 women. The prevalence of HSIL was 19.3% in women with a persistent HPV infection at a younger age. This is significantly higher (p<0,001) compared with the HSIL prevalence of 1.5% in HPV-negative women, and 3.1% (n = 8) in women who cleared the hrHPV infection in the past.

Conclusion

Women with a persistent hrHPV infection in their 20s, show an increased prevalence of HSIL lesions in their early 30s. Screening for persistent hrHPV infections, instead of cytology screening before the age of 30, can be used to reduce the future prevalence of cervical cancer in young women.

Human papilloma virus and genitourinary cancers: a narrative review

INTRODUCTION

Human papilloma virus (HPV) is the most common sexually transmitted pathogen and its potential role in the genesis of several diseases such as cervical, head and neck, anal and penile cancers, is now largely recognized. Aim of this review article was to evaluate and summarize the state of the art of HPV-related urogenital cancers, focusing on the potentially innovative methods for the diagnosis of infection that should be used to improve viral causative detection and prevent its diffusion through sexual intercourses.

EVIDENCE ACQUISITION

The initial search was carried out by using the Medline and the Google Scholar computerized databases through the selected key-words to identify the more recent literature on HPV epidemiology and its relationship with the main relevant urinary tract cancers. Studies were selected, extracted, analyzed and summarized. The PRISMA statement criteria were adopted and reported.

EVIDENCE SYNTHESIS

Polymerase chain reaction assay (HPV test) represents the best option for the diagnosis of HPV infection. Difficulties for the diagnosis in male are due to the site of investigation (glans, sub coronal sulcus, scrotum, urine, sperm) and the method adopted to take the sample (brushing, tissue biopsy). Due to these reasons several studies analyzed seemed to be incomparable. HPV infection is generally found in about 20% of heterosexual men. Its connection with cervical, anal, head and neck and penile cancer has been previously evidenced in 90%, 60%, 68% and 40% of cases respectively. In particular, HPV infection differed significantly among penile squamous cell carcinoma (SCC) subtypes ranging from 22.4% in verrucous subtype to 66.3% for the basaloid/warty subtype. Although the connection between prostate cancer and HPV infection has never been previously confirmed, forest plot analysis relative to a series of nine studies done during the last ten years, demonstrated a 7.7 objective risk (OR) for subjects with HPV infection to develop subsequent prostate cancer. On the other hand, some authors found comparable results in subjects with prostate cancer, benign prostate hyperplasia and prostate inflammation, thus demonstrating that this link still remains questionable. Similarly, the connection between HPV infection and urothelial, testicular and renal cancer continue to be hotly debated although HPV has been found in the urine, semen and renal tissue of patients respectively.

CONCLUSIONS

Integrated parts of HPV (E6 and E7 fractions) have been previously found in cervical, head and neck, anal and penile cancers. Conversely, although the evidence of concomitant HPV infection, integrated viral genome in cancer cells DNA had never been demonstrated in all the other genito-urinary tract cancers, and its role in the tumor genesis remain still largely debated. This is the reason why HPV infection should be tested in all patients with genitourinary cancer to better investigate about its potential role in the tumor genesis and development. Moreover, HPV infection option should be kept in mind when considering possible viral transmission to sexual partners.

HPV test by Hybrid Capture II for the diagnosis of HR-HPV persistent infection

INTRODUCTION

Persistent high-risk HPV (HR-HPV) infection is associated with a greater risk of cervical cancer.

PATIENTS AND METHODS

Statistical data on the prevalence of HR-HPV infections in the Algerian population is lacking. We conducted a prospective study of 300 women aged between 25 and 50 years, screened for cervical cancer from 2012 to 2015 in Sidi Bel Abbès, a western region of Algeria. We aimed to assess the reliability of the repeated use of the HC II test (three longitudinal HPV tests 9 months apart from each other) in diagnosing the persistence of HR-HPV infection.

RESULTS

The prevalence of HR-HPV infection was 7.33% and infected women were aged 37.9±3years. For 90.9% of HR-HPV-positive patients, the infection persisted for a mean of 18.5months [95% CI: 16.9-22.1months]. Among these patients, 55.55% developed CIN1 and 11.11% developed CIN2. The sensitivity of the HC II test was 81.74% [95% CI: 71.3-89.6] and its positive predictive value associated with abnormal cervical biopsy was 27.49% [95% CI: 16.0-33.33].

CONCLUSION

Repeating the HC II test is a good predictor for identifying women at high risk of cervical cancer.

Rates and determinants of incidence and clearance of cervical HPV genotypes among HIV-seropositive women in Pune, India

BACKGROUND

Several studies in recent years have documented the genotype-specific prevalence of HPV infection and wide diversity and multiplicity of HPV genotypes among HIV-seropositive women. Yet, information on changes in HPV genotype-specific incidence and clearance rates over time, and their correlation with clinical or immunologic factors among HIV-seropositive women is scarce.

OBJECTIVES

We conducted a prospective study to investigate the incidence and clearance rates of cervical HPV genotypes among HIV-seropositive women in India and expand the evidence base in this area of research.

STUDY DESIGN

Cervical samples were collected from n=215 HIV-seropositive women in Pune, India who underwent two screening visits separated by a median of 11-months (interquartile range: 8-18 months). HPV genotypes were determined by Roche Linear Array HPV assay. Individual genotype-specific and carcinogenicity-grouping-specific HPV incidence and clearance rates were calculated and the associations between incidence/clearance and age and HIV-related metrics were explored.

RESULTS

Incidence and clearance rates for 'any HPV' and 'carcinogenic HPV' genotypes were 11.1 and 18.3, and 6.7 and 33.8, per 100 person-years, respectively. Incidence and clearance rates for HPV genotypes of alpha-9 species (HPV16, HPV31, HPV33, HPV35, HPV52 and HPV58) and alpha-7 species (HPV18, HPV39, HPV45, HPV59 and HPV68) were 5.8 and 2.04, and 32.1 and 53.5, per 100 person-years, respectively. Clearance of any HPV type was associated with increasing age of participants (odds ratio: 1.08, 95%CI: 1.004-1.17), although the association marginally lost its statistical significance when adjusted for CD4 counts and antiretroviral therapy status.

CONCLUSIONS

Genotype-specific clearance rates of HPV were higher than corresponding incidence rates. The suggestion of a positive associations of increasing age with HPV clearance points to the need for etiologic studies on age-related hormonal changes on clearance of cervical HPV infection.

Short-term natural history of high-risk human papillomavirus infection in mid-adult women sampled monthly

Characterizing short-term HPV detection patterns and viral load may inform HPV natural history in mid-adult women. From 2011-2012, we recruited women aged 30-50 years. Women submitted monthly self-collected vaginal samples for high-risk HPV DNA testing for 6 months. Positive samples were tested for type-specific HPV DNA load by real-time PCR. HPV type-adjusted linear and Poisson regression assessed factors associated with (i) viral load at initial HPV detection and (ii) repeat type-specific HPV detection. One-hundred thirty-nine women (36% of 387 women with ≥4 samples) contributed 243 type-specific HR HPV infections during the study; 54% of infections were prevalent and 46% were incident. Incident (vs. prevalent) detection and past pregnancy were associated with lower viral load, whereas current smoking was associated with higher viral load. In multivariate analysis, current smoking was associated with a 40% (95% CI: 5-87%) increase in the proportion of samples that were repeatedly positive for the same HPV type, whereas incident (vs. prevalent) detection status and past pregnancy were each associated with a reduction in the proportion of samples repeatedly positive (55%, 95% CI: 38-67% and 26%, 95% CI: 10-39%, respectively). In a separate multivariate model, each log10 increase in viral load was associated with a 10% (95% CI: 4-16%) increase in the proportion of samples repeatedly positive. Factors associated with repeat HPV detection were similar to those observed in longer-term studies, suggesting that short-term repeat detection may relate to long-term persistence. The negative associations between incident HPV detection and both viral load and repeat detection suggest that reactivation or intermittent persistence was more common than new acquisition.

Alcohol consumption and persistent infection of high-risk human papillomavirus

Alcohol consumption is a possible co-factor of high-risk human papillomavirus (HR-HPV) persistence, a major step in cervical carcinogenesis, but the association between alcohol and continuous HPV infection remains unclear. This prospective study identified the association between alcohol consumption and HR-HPV persistence. Overall, 9230 women who underwent screening during 2002-2011 at the National Cancer Center, Korea were analysed in multivariate logistic regression. Current drinkers [odds ratio (OR) 2·49, 95% confidence interval (CI) 1·32-4·71] and drinkers for ⩾5 years (OR 2·33, 95% CI 1·17-4·63) had a higher risk of 2-year HR-HPV persistence (HPV positivity for 3 consecutive years) than non-drinkers and drinkers for <5 years, respectively (vs. HPV negativity for 3 consecutive years). A high drinking frequency (⩾twice/week) and a high beer intake (⩾3 glasses/occasion) had higher risks of 1-year (OR 1·80, 95% CI 1·01-3·36) HPV positivity for 2 consecutive years) and 2-year HR-HPV persistence (OR 3·62, 95% CI 1·35-9·75) than non-drinkers. Of the HPV-positive subjects enrolled, drinking habit (OR 2·68, 95% CI 1·10-6·51) and high consumption of beer or soju (⩾2 glasses/occasion; OR 2·90, 95% CI 1·06-7·98) increased the risk of 2-year consecutive or alternate HR-HPV positivity (vs. consecutive HPV negativity). These findings suggest that alcohol consumption might increase the risk of cervical HR-HPV persistence in Korean women.

Optimal positive cutoff points for careHPV testing of clinician- and self-collected specimens in primary cervical cancer screening: an analysis from rural China

careHPV, a lower-cost DNA test for human papillomavirus (HPV), is being considered for cervical cancer screening in low- and middle-income countries. However, not a single large-scaled study exists to investigate the optimal positive cutoff point of careHPV test. We pooled data for 9,785 women participating in two individual studies conducted from 2007 to 2011 in rural China. Woman underwent multiple screening tests, including careHPV on clinician-collected specimens (careHPV-C) and self-collected specimens (careHPV-S), and Hybrid Capture 2 on clinician-collected specimens (HC2-C) as a reference standard. The primary endpoint was cervical intraepithelial neoplasia grade 3 or more severe (CIN3+) (n = 127), and secondary endpoint was CIN2+ (n = 213). The area under the curves (AUCs) for HC2-C and careHPV-C were similar (0.954 versus 0.948, P = 0.166), and better than careHPV-S (0.878; P < 0.001 versus both). The optimal positive cutoff points for HC2-C, careHPV-C, and careHPV-S were 1.40, 1.74, and 0.85, respectively. At the same cutoff point, careHPV-C was not significantly less sensitive and more specific for CIN3+ than HC2-C, and careHPV-S was significantly less sensitive for CIN3+ than careHPV-C and HC2-C. Raising the cutoff point of careHPV-C from 1.0 to 2.0 could result in nonsignificantly lower sensitivity but significantly higher specificity. Similar results were observed using CIN2+ endpoint. careHPV using either clinician- or self-collected specimens performed well in detecting cervical precancer and cancer. We found that the optimal cutoff points of careHPV were 2.0 on clinician-collected specimens and 1.0 on self-collected specimens.

A prospective study of age trends of high-risk human papillomavirus infection in rural China

BACKGROUND

In China, high-risk human papillomavirus (HR-HPV) prevalence is unexpectedly high in older women, but the possible reasons have not been well studied yet. This study investigated the age trends of HR-HPV infection in a prospective study.

METHODS

A total of 7397 women aged 25-65 years without cervical precancer or cancer were evaluated during 2010-2011 with a stratified sample of 2791 women re-evaluated after one year. Test results for careHPV and careHPV16/18/45 were used to describe the HR-HPV prevalence, incidence and clearance. Risk factors associated with HR-HPV infections were explored using a logistic regression model.

RESULTS

The overall HR-HPV prevalence was 13.1% at baseline, with a peak of 19.3% in women aged 55-59 years. The prevalence of HR-HPV (p for trends < 0.001), HPV16/18/45 (p for trends = 0.002), and HR-HPV other than HPV16/18/45 (p for trends = 0.002) generally increased with increasing age. Number of infections that cleared was generally greater than number of incident infections within age groups. One-year clearance rate decreased with increasing age (p for trends < 0.001), however, incidence rate was unrelated to age (p for trends = 0.159). Risk factors that associated with HR-HPV infection differed between younger and older women.

CONCLUSIONS

The greater HR-HPV prevalence in older versus younger women in rural China may be explained by a cohort effect, higher than expected incidence, and/or poorer clearance at older age.

HPV clearance in postpartum period of HIV-positive and negative women: a prospective follow-up study

BACKGROUND

HPV persistence is a key determinant of cervical carcinogenesis. The influence of postpartum on HPV clearance has been debated. This study aimed to assess HPV clearance in later pregnancy and postpartum among HIV-positive and negative women.

METHODS

We conducted a follow-up study with 151 HPV-positive women coinfected with HIV, in 2007-2010. After baseline assessment, all women were retested for HPV infection using PCR in later pregnancy and after delivery. Multivariable logistic regressions assessed the putative association of covariates with HPV status in between each one of the successive visits.

RESULTS

Seventy-one women (47%) have eliminated HPV between the baseline visit and their second or third visits. HIV-positive women took a significantly longer time (7.0 ± 3.8 months) to clear HPV, compared to those not infected by HIV (5.9 ± 3.0 months). HPV clearance was significantly more likely to take place after delivery than during pregnancy (84.5% x 15.5%).

CONCLUSIONS

Both HIV-positive and negative women presented a significant reduction in HPV infection during the postpartum period. HIV-positive status was found to be associated with a longer period of time to clear HPV infection in pregnant women.

Viral load and short-term natural history of type-specific oncogenic human papillomavirus infections in a high-risk cohort of midadult women

Oncogenic human papillomavirus (HPV) viral load may inform the origin of newly detected infections and characterize oncogenic HPV natural history in midadult women. From 2007 to 2011, we enrolled 521 25-65-year-old-female online daters and followed them triannually with mailed health and sexual behavior questionnaires and kits for self-sampling for PCR-based HPV DNA testing. Samples from oncogenic HPV positive women were selected for type-specific DNA load testing by real-time PCR with adjustment for cellularity. Linear or logistic regression models were used to evaluate relationships between viral levels, health and sexual behavior, and longitudinal oncogenic HPV detection. Type-specific viral levels were borderline significantly higher in oncogenic HPV infections that were prevalent versus newly detected (p = 0.092), but levels in newly detected infections were higher than in infections redetected after intercurrent negativity (p < 0.001). Recent sex partners were not significantly associated with viral levels. Compared with prevalent infections detected intermittently, the likelihood of persistent (OR = 4.31, 95% CI: 2.20-8.45) or single-time (OR = 1.32, 95% CI: 1.03-1.71) detection increased per 1-unit increase in baseline log10 viral load. Viral load differences between redetected and newly detected infections suggest a portion of new detections were due to new acquisition, although report of recent new sex partners (a potential marker of new infection) was not predictive of viral load; oncogenic HPV infections in midadult women with new partners likely represent a mix of new acquisition and reactivation or intermittent detection of previous infection. Intermittent detection was characterized by low viral levels, suggesting that intermittent detection of persisting oncogenic HPV infection may be of limited clinical significance.

Patterns of persistent genital human papillomavirus infection among women worldwide: a literature review and meta-analysis

Persistent high-risk human papillomavirus (HR-HPV) infection is the strongest risk factor for high-grade cervical precancer. We performed a systematic review and meta-analysis of HPV persistence patterns worldwide. Medline and ISI Web of Science were searched through January 1, 2010 for articles estimating HPV persistence or duration of detection. Descriptive and meta-regression techniques were used to summarize variability and the influence of study definitions and characteristics on duration and persistence of cervical HPV infections in women. Among 86 studies providing data on over 100,000 women, 73% defined persistence as HPV positivity at a minimum of two time points. Persistence varied notably across studies and was largely mediated by study region and HPV type, with HPV-16, 31, 33 and 52 being most persistent. Weighted median duration of any-HPV detection was 9.8 months. HR-HPV (9.3 months) persisted longer than low-risk HPV (8.4 months), and HPV-16 (12.4 months) persisted longer than HPV-18 (9.8 months). Among populations of HPV-positive women with normal cytology, the median duration of any-HPV detection was 11.5 and HR-HPV detection was 10.9 months. In conclusion, we estimated that approximately half of HPV infections persist past 6 to 12 months. Repeat HPV testing at 12-month intervals could identify women at increased risk of high-grade cervical precancer due to persistent HPV infections.

Topical imiquimod treatment for human papillomavirus infection in patients with and without cervical/vaginal intraepithelial neoplasia

OBJECTIVE

To evaluate the efficacy and toxicity of topical imiquimod for the treatment of persistent human papillomavirus (HPV) infection in patients with or without cervical/vaginal intraepithelial neoplasia (CIN/VAIN).

METHODS

Patients with persistent HPV infection (≥ 1 year) after a history of treatment for cervical or vaginal neoplasm but normal histology and cytology, abnormal Papanicolaou (Pap) smears without abnormal histology, and untreated histology-documented CIN/VAIN Grade 1/2/3 with HPV-positive testing were recruited. Patients were instructed to apply 250 mg of 5% imiquimod cream intravaginally on consecutive days or at least twice weekly on an outpatient basis for a minimum of 12 doses. A group of age- and previous diagnosis-matched, imiquimod-untreated historical controls (n = 20) were selected. The main outcome measures included HPV DNA detection, cytology, and colposcopy/histology at 6 months after treatment.

RESULTS

A total of 72 patients were eligible for analysis. At a median follow-up of 33.6 months, 37 patients (51.4%) had cytological/histological regression and tested HPV-negative. Six patients (8.3%) had progressive cytology/histology with persistent HPV infections. Of the 72 treated patients, 26 patients who had a normal Pap test but were persistently HPV-positive for at least 1 year had a complete regression rate of 65.4%, which was significantly different from the rate (30%) observed in the untreated historical control (p = 0.036). Six patients with histologically proven CIN2/3 or VAIN2/3 had a complete regression rate of 66.6% (4/6).

CONCLUSIONS

The tolerability of intravaginal self-administered imiquimod is confirmed. Its efficacy in the treatment of women with persistent HPV infection and normal cytology warrants further randomized, controlled trials to determine appropriate dosages and scheduling.

Prevalence of human papillomavirus genotypes among women in Hunan province, China

OBJECTIVE

Human papillomavirus (HPV) infection has been implicated as a causative factor of cervical cancer. This study aimed to examine HPV genotype distribution and prevalence among women in Hunan province, mid-south China.

STUDY DESIGN

Cervical samples were collected from 3640 women for cervical cancer screening. Participants were screened by cytology, and HPV genotyping was performed by DNA chip.

RESULTS

Of the 3640 cases, 22.6% (822/3640) were HPV DNA positive, of whom 19.0% (156/822) had multiple infections and 20.0% (726/3640) were confirmed to have high-risk HPV infection. The most common HPV genotype was HPV-16, followed by -52, -58, -18, -6 and -39. Cytological examination showed that the HPV positive rate was 59.3% (80/135) in women with atypical squamous cells of undetermined significance, 66.1% (111/168) in women with low-grade squamous intra-epithelial lesions, 72.6% (106/146) in women with high-grade squamous intra-epithelial lesions, and 87.2% (68/78) in women with invasive cervical cancer, all of which were significantly higher than the rate in women with normal squamous cells (14.3%, 451/3115).

CONCLUSION

This is the first study to report the prevalence and genotype distribution of HPV infection among women in Hunan province, China. The findings provide important guidance for a vaccination programme in this region aimed at immunizing women before they are infected with HPV.

Prospective follow-up of 2,065 young unscreened women to study human papillomavirus incidence and clearance

Human papillomavirus (HPV) is a necessary factor in the development of cervical intraepithelial neoplasia and cervical cancer. However, HPV is also a very common sexually transmitted virus and many women clear their infection. To study HPV incidence and clearance, 2,065 women, aged 18-29 years, were followed for 12 months and were asked to provide a self-collected cervico-vaginal sample and fill-out a questionnaire every 3 months. For HPV DNA detection, the SPF10 -DEIA LiPA25 system was used. Incidence rates of any-type high-risk HPV and low-risk HPV were 17.0 per 1,000-person months, and 14.3 per 1,000-person months, respectively. HPV types 16, 52, 51 and 31 had the highest type-specific incidence rates. HPV incidence was increased in singles, and women having a new relationship. A higher number of lifetime sex partners, and a higher frequency of sexual contacts in the past 3 months was associated with an increased HPV incidence. The overall clearance of the newly detected type-specific high-risk HPV infections and low-risk HPV infections was 61.2% and 69.0%, respectively. Having a sexual relationship compared to being single, and a higher sexual age both positively influenced the clearance of any-type high-risk HPV. Among the women infected with HPV 16, the women who had a co-infection had a lower proportion of clearance of HPV 16. In conclusion, in this young Dutch study population, HPV incidence rates are not related to age and comparable to other western countries. Clearance was only independently related to factors associated with sexual behavior, either past or current.

Genetic variability in L1 and L2 genes of HPV-16 and HPV-58 in Southwest China

HPV account for most of the incidence of cervical cancer. Approximately 90% of anal cancers and a smaller subset (<50%) of other cancers (oropharyngeal, penile, vaginal, vulvar) are also attributed to HPV. The L1 protein comprising HPV vaccine formulations elicits high-titre neutralizing antibodies and confers type restricted protection. The L2 protein is a promising candidate for a broadly protective HPV vaccine. In our previous study, we found the most prevalent high-risk HPV infectious serotypes were HPV-16 and HPV-58 among women of Southwest China. To explore gene polymorphisms and intratypic variations of HPV-16 and HPV-58 L1/L2 genes originating in Southwest China, HPV-16 (L1: n = 31, L2: n = 28) and HPV-58 (L1: n = 21, L2: n = 21) L1/L2 genes were sequenced and compared to others described and submitted to GenBank. Phylogenetic trees were then constructed by Neighbor-Joining and the Kimura 2-parameters methods (MEGA software), followed by an analysis of the diversity of secondary structure. Then selection pressures acting on the L1/L2 genes were estimated by PAML software. Twenty-nine single nucleotide changes were observed in HPV-16 L1 sequences with 16/29 non-synonymous mutations and 13/29 synonymous mutations (six in alpha helix and two in beta turns). Seventeen single nucleotide changes were observed in HPV-16 L2 sequences with 8/17 non-synonymous mutations (one in beta turn) and 9/17 synonymous mutations. Twenty-four single nucleotide changes were observed in HPV-58 L1 sequences with 10/24 non-synonymous mutations and 14/24 synonymous mutations (eight in alpha helix and four in beta turn). Seven single nucleotide changes were observed in HPV-58 L2 sequences with 4/7 non-synonymous mutations and 3/7 synonymous mutations. The result of selective pressure analysis showed that most of these mutations were of positive selection. This study may help understand the intrinsic geographical relatedness and biological differences of HPV-16/HPV-58 and contributes further to research on their infectivity, pathogenicity, and vaccine strategy.

Behavioral and sociodemographic risk factors for serological and DNA evidence of HPV6, 11, 16, 18 infections

INTRODUCTION

Risk for HPV6/11/16/18 infections in young sexually active, behaviorally low-risk females is not well described and may inform public policy.

METHODS

To assess exposure risk for HPV/6/11/16/18 among 16-23 year old low-risk females, data for 2409 female clinical trial participants were evaluated. Baseline visit self-reported sexual, behavioral and demographic characteristics; and results from HPV genotyping and serology, and other clinical laboratory assays were analyzed. All subjects reported <5 lifetime male sexual partners and no prior abnormal cytology at baseline.

RESULTS

While 98% (2211/2255) were naïve to HPV16 or 18 and 99.6% (2246/2255) were naïve for 1-3 index HPVs, 27% (616/2255) showed antibody, DNA or both for ≥1 index HPV. While 18% (409/2255) tested HPV16- or -18-antibody- or -DNA-positive, only 2% (44/2255) tested positive for both types. Against this high background, other sexually transmitted infections (STIs) were uncommonly detected, suggesting low sexual risk-taking behavior. The adjusted analyses showed race, age, alcohol consumption, current Chlamydia trachomatis (chlamydia) and Trichamonas vaginalis (trichomoniasis), bacterial vaginosis (BV), number of lifetime male sex partners predicted positive index-HPV antibody test results. However, only the number of male sex partners predicted positivity for HPV6/11- and 16/18-DNA, and chlamydia infection predicted positivity for HPV6/11-DNA alone.

CONCLUSIONS

Taken together, type-specific HPV-DNA and -antibody evidence of HPV6/11/16/18 infections among behaviorally low-risk 16-23 year old females is high. Since almost all participants would have benefited by either currently available bivalent or quadrivalent vaccine strategies, delaying vaccination beyond menarche may be a missed opportunity to fully protect young females against HPV6/11/16/18 infections and related dysplasias. Early diagnosis and treatment of chlamydia and trichomonas may be important in HPV pathogenesis.

Human papillomavirus persistence in young unscreened women, a prospective cohort study

Objective

To evaluate hr-HPV persistence and associated risk factors in a prospective cohort of young unscreened women. Additionally, the relation between hr-HPV status and cytology/histology results is examined.

Methods and Principal Findings

Two year follow-up of 235 out of 2065 young women (18–29 years), participating in a large, one year epidemiological study, with questionnaires, self-collected cervico-vaginal samples (Vibabrush), and SPF₁₀LiPA for HPV detection. Only women hr-HPV positive at sample month 12 were invited for a second year of follow-up. After study follow-up, available cytology/histology data were requested from PALGA (the national network and registry of histo- and cytopathology in The Netherlands). These data were compared with available cytology/histology data of the month 12 hr-HPV negative women from the same cohort. 44.1% of the hr-HPV types detected at study month 12, persisted during follow-up. HPV types 45, 31, 16 and 18 were most likely to persist with percentages of 60.0%, 56.8%, 54.4%,and 50.0%, respectively. Compared to newly detected infections at month 12, infections present since 6 months or baseline had an increased risk to persist (OR 3.09 [95% CI: 1.74–5.51] and OR 4.99 [95% CI: 2.67–9.32], respectively). Other co-factors influencing persistence were, multiple HPV infections, smoking and multiple lifetime sexual partners. The percentage of women with a HSIL/CIN2+ (12.1%) in the persistent HPV group, was not significantly different (p = 0.107) from the 5.3% of the women who cleared the hr-HPV infection, but was significantly (p 0.000) higher than to the 1.6% of women in the hr-HPV negative control group.

Conclusion

We showed that HPV genotype, multiple infections, smoking, and multiple lifetime sexual partners are co-factors that increase the risk of hr-HPV persistency. Most importantly, we showed that hr-HPV infections are more likely to persist the longer they have been present and that women with a persistent hr-HPV infection have a high risk of HSIL/CIN2+ development.

Evaluation of type-specific HPV persistence and high-risk HPV viral load quantitation in HPV positive women under 30 with normal cervical cytology

The persistence of high-risk HPV (HR-HPV) infection is necessary for the development of cervical intraepithelial neoplasia. The aim of this study was to evaluate if HR-HPV typing and HPV16, 18, 31, and 33 quantitation are predictive for type-specific infection persistence and/or the development of CIN in women under 30 with normal cervical cytology. Young women (under 30) attending a family planning clinic who were HPV positive with normal cervical cytology were included. HPV genotyping was assessed by MY09/MY11 PCR, sequencing, phylogenetic analysis, and cloning when necessary. HR-HPV viral load was quantified using duplex real-time PCR. Study patients were offered for a second smear and HR-HPV detection and quantitation after 12 months. HR-HPV was identified in 43 (21.9%) of the 199 included women. Of these, 39 patients had a second cervical sample taken within a mean interval of 11.7 months (8.8-18.3 months). The mean HR-HPV 16, 18, 31, and 33 initial viral load was 1.9 × 10(6) copies/million cells. The level of viral load did not reveal any significant association with type-specific HR-HPV persistence or the subsequent development of cervical intraepithelial neoplasia. Only HPV16 infection was significantly more likely to persist (91.7% vs. 33.1%, P=0.001) and to develop CIN (33.3% vs. 3.7%, P=0.025). In women under 30 with normal cytology, HR-HPV viral load is common and is not predictive of HPV persistence or the development of cervical intraepithelial neoplasia. HPV16 positive women are significantly more likely to have persistent infection and to develop cervical intraepithelial neoplasia.

Viral load in the natural history of human papillomavirus type 16 infection: a nested case-control study

BACKGROUND

Viral load may influence the course of human papillomavirus type 16 (HPV-16) infection.

METHODS

This case-control study was nested within the 2-year Atypical Squamous Cells of Undetermined Significance and Low-Grade Squamous Intraepithelial Lesion Triage Study, in which women were followed semiannually for HPV and cervical intraepithelial neoplasia (CIN). Case patients (n = 62) were women diagnosed with CIN3 following HPV-16-positive detection at a follow-up visit. HPV-16-positive controls (n = 152) without CIN2 or CIN3 were matched to cases based on the follow-up visit in which viral load was measured. Real-time polymerase chain reaction was used for HPV-16 DNA quantification.

RESULTS

The risk of CIN3 increased with increasing HPV-16 DNA load at the follow-up visit (odds ratio, 1.63; 95% confidence interval, 1.33-1.99 per 1 log(10) unit increase); the association was not affected by whether HPV-16 was present at enrollment. When HPV-16 was present at both enrollment and follow-up, viral load remained high among cases (P = .77) but decreased substantially among controls (P = .004). Among women with HPV-16 found initially during follow-up, viral load in the first HPV-16-positive sample was associated with short-term persistence; load was higher in those with infection, compared with those without infection, 1 visit after the initial positivity (P = .001).

CONCLUSIONS

Viral load of newly detected infections and changes in viral load predict persistence and progression of HPV-16 infections.

Genotype-specific clearance of genital human papillomavirus (HPV) infections among mothers in the Finnish family HPV study

The majority of cervical human papillomavirus (HPV) infections in young women are transient, but whether the clearance differs among different HPV genotypes and the different factors predicting genotype-specific clearance are partly unknown. In the Finnish Family HPV Study, 131 of 252 women (mean age, 25.5 years) cleared their infection during the prospective follow-up of 6 years (median, 62.4 months; range, 1.6 to 94.5 months). Cervical scrapings collected at each visit were tested for 24 low-risk and high-risk (HR) HPV types with multiplex HPV genotyping. Poison regression (panel data) was used to estimate predictors for the clearance of species 7 and 9 HPV genotypes. Of all HPV genotypes detected in these women, multiple-type and HPV type 16 (HPV16) infections showed clearance least frequently (46.1% and 50.5%, respectively). The actuarial and crude mean times to first clearance were variable among different genotypes. The actuarial clearance rate (events/person-time at risk) was highest for HPV16 and multiple-type infections, while HPV66 and -82 had the highest crude clearance rate. Independent predictors increasing type-specific clearance of species 7/9 HPV genotypes were older age (incidence rate ratio [IRR] = 1.1; 95% confidence interval [95% CI], 1.03 to 1.18; P = 0.002) and baseline oral HR HPV DNA-negative status (IRR = 2.94; 95% CI, 1.03 to 8.36; P = 0.042), while a higher number of sexual partners during the follow-up decreased the probability of clearance (IIR = 0.35; 95% CI, 0.15 to 0.83; P = 0.018). To conclude, HPV16 and multiple-type infections showed the lowest clearance among young mothers. Increasing age and negative oral HR HPV DNA status at baseline were associated with increased clearance, whereas a higher number of current sexual partners decreased the probability of species 7/9 HPV genotype clearance.

Predictors of human papillomavirus persistence among women with equivocal or mildly abnormal cytology

We investigated short-term persistence of human papillomavirus (HPV) infection among 2,408 women with low-grade or equivocal cytological abnormalities followed for 24 months. Odds ratios (ORs) for persistence to the next 6-month visit were estimated by a discrete time survival model. Prevalent HPV infections persisted longer in older women, but no association with age was found for incident HPV infections. Increased likelihood of persistence was found among current smokers of >20 cigarettes per day compared with smokers of <or=10 cigarettes per day (OR=1.43; 95% confidence interval [CI]: 1.02-2.01) and among current injectable contraceptive users (OR=1.15; 95% CI: 1.01-1.32). Persistence was more likely among infections with higher viral load (OR=2.05; 95% CI: 1.65-2.53) or with concurrent cytological abnormalities (OR=1.19; 95% CI: 1.03-1.39 and 1.29; 95% CI: 0.99-1.70 for ASCUS/LSIL and ASC-H/HSIL, respectively). We conclude that new HPV infections in older women are not riskier by the metric of viral persistence than those in younger women. Other risk factors such as oral contraceptive use and multiparity that have been associated with cervical cancer or cervical intraepithelial neoplasia grade 3 were not associated with short-term HPV persistence.

Human Papillomavirus (HPV) type 16 and type 18 DNA Loads at Baseline and Persistence of Type-Specific Infection during a 2-year follow-up

BACKGROUND

Studies of viral load-associated persistence of human papillomavirus (HPV) infection are rare, with inconsistent results reported.

METHODS

The study subjects were 741 and 289 women who were positive for HPV type 16 (HPV-16) and HPV type 18 (HPV-18), respectively, at the time of enrollment into in the ASCUS-LSIL (Atypical Squamous Cells of Undetermined Significance-Low-Grade Squamous Intraepithelial Lesion) Triage Study and who returned 1 or more times for HPV testing during a biannual 2-year follow-up. The numbers of HPV-16 and HPV-18 copies per nanogram of cellular DNA at baseline were measured by use of real-time polymerase chain reaction.

RESULTS

Women with, compared with women without, persistent infection at month 6 of follow-up had a higher viral load at enrollment (P< .001, for HPV-16; P=.01, for HPV-18). The association of each 1-log(10) increase in viral load with persistence of HPV-16 or HPV-18 during the first 6 months of the study was statistically significant among women with multiple HPV types at enrollment (for HPV-16: odds ratio [OR], 1.53 [95% confidence interval {CI}, 1.29-1.82]; for HPV-18: OR, 1.35 [95% CI, 1.09-1.68]) but not among women with monotype infections (in tests assessing the interaction between viral load and coinfection, P=.002 for HPV-16 and P=.34 for HPV-18). Among women who continued to have positive results at month 6, 12, or 18, persistence of infection for another 6 months was unassociated with the viral load at baseline.

CONCLUSION

Prevalent infection with a higher viral load of HPV-16 or HPV-18 was associated with short- but not long-term persistence.