Patterns of cervical coinfection with multiple human papilloma virus types in a screening population in Denmark

Predictable changes in the accuracy of human papillomavirus tests after vaccination: review with implications for performance monitoring in cervical screening

Vaccination against human papillomavirus (HPV) is changing the performance of cytology as a cervical screening test, but its effect on HPV testing is unclear. We review the effect of HPV16/18 vaccination on the epidemiology and the detection of HPV infections and high-grade cervical lesions (CIN2+) to evaluate the likely direction of changes in HPV test accuracy. The reduction in HPV16/18 infections and cross-protection against certain non-16/18 high-risk genotypes, most notably 31, 33, and/or 45, will likely increase the test's specificity but decrease its positive predictive value (PPV) for CIN2+. Post-vaccination viral unmasking of non-16/18 genotypes due to fewer HPV16 co-infections might reduce the specificity and the PPV for CIN2+. Post-vaccination clinical unmasking exposing a higher frequency of CIN2+ related to non-16/18 high-risk genotypes is likely to increase the specificity and the PPV of HPV tests. The effect of HPV16/18 vaccination on HPV test sensitivity is difficult to predict based on these changes alone. Programmes relying on HPV detection for primary screening should monitor the frequency of false-positive and false-negative tests in vaccinated (younger) vs. unvaccinated (older) cohorts, to assess the outcomes and performance of their service.

Human Papillomavirus Same Genotype Persistence and Risk: A Systematic Review

OBJECTIVE

The aim of the study was to examine whether high-grade cervical intraepithelial neoplasia (CIN) was more closely associated with human papillomavirus (HPV) same-genotype persistence (SGTP) versus clearance of prior infection with a subsequent infection by a new genotype (genotype switch [GS]), clearance of HPV infection, or acquisition of a new HPV infection after a negative infection status, during a follow-up testing subsequent to abnormal screening results.

MATERIALS AND METHODS

MEDLINE, Cochrane Library, Health Technology Assessment, and clinicaltrials.gov were searched from January 2000 to July 2019 for prospective controlled trials and observational studies of women and retrospective studies using HPV assays with extended- or full-genotype reporting. The primary outcome was high-grade CIN after at least 2 rounds of testing. Overall quality of evidence for the risk estimate outcomes was assessed. Of the 830 identified abstracts, 66 full-text articles were reviewed, and 7 studies were included in the synthesis. The study protocol was registered with the PROSPERO International Prospective Register of Systematic Reviews (CRD42018091093).

RESULTS

Continued HPV-positive women falls in 2 equally large groups: SGTP and GS. Sensitivity, positive predictive value, and positive likelihood ratio of SGTP were significantly higher than for GS. Human papillomavirus genotypes may be ranked into 3 tiers (immediate colposcopy, follow-up testing, return to routine screening), according to associated risk of persistence for high-grade CIN and to prevailing clinical action thresholds.

CONCLUSIONS

There is moderately high-quality evidence to support the clinical utility of SGTP to improve risk discrimination for high-grade CIN compared with qualitative HPV testing without genotype-specific information.

Concurrent infection with multiple human papillomavirus types among unvaccinated and vaccinated 17-year-old Norwegian girls

Background

Whether type-specific human papillomavirus (HPV) infection influences the risk of acquiring infections with other HPV types is unclear. We studied concurrent HPV infections in 17-year-old girls from 2 birth cohorts; the first vaccine-eligible cohort in Norway and a prevaccination cohort.

Methods

Urine samples were collected and tested for 37 HPV genotypes. This study was restricted to unvaccinated girls from the prevaccination cohort (n = 5245) and vaccinated girls from the vaccine-eligible cohort (n = 4904). Risk of HPV infection was modelled using mixed-effect logistic regression. Expected frequencies of concurrent infection with each pairwise combination of the vaccine types and high-risk types (6/11/16/18/31/33/35/39/45/51/52/56/58/59) were compared to observed frequencies.

Results

Infection with multiple HPV types was more common among unvaccinated girls than vaccinated girls (9.2% vs 3.7%). HPV33 and HPV51 was the only HPV pair that was detected together more often than expected among both unvaccinated (P = .002) and vaccinated girls (P < .001). No HPV pairs were observed significantly less often than expected.

Conclusions

HPV33 and HPV51 tended to be involved in coinfection among both unvaccinated and vaccinated girls. The introduction of HPV vaccination does not seem to have had an effect on the tendency of specific HPV types to cluster together.

HPV Testing for Cervical Cancer in Romania: High-Risk HPV Prevalence among Ethnic Subpopulations and Regions

BACKGROUND

Romania has had one of the highest rates of cervical cancer incidence and mortality in Europe for decades. Data on the high-risk human papillomavirus (hrHPV) prevalence within the Romanian population are crucial for cervical cancer intervention in high risk groups. The aim of this study was to determine the prevalence of hrHPV infection in Romania, identifying high-risk areas for cervical cancer prevention efforts.

METHODS

The target population of this study were women of all forms in Romania, including ethnic minorities, women from urban and rural areas, and women in various regions. Women with no history of precancerous or cancerous lesions were offered hrHPV screening. The specimens were tested with Hybrid Capture 2 (HC2) DNA test. Age-standardized hrHPV prevalence rates with 95% confidence intervals (CI) were estimated.

RESULTS

hrHPV results of 2060 women aged 18 to 70 years were analyzed. The highest hrHPV prevalence rates were observed among: Romanians (17.9%; 95 CI: 15.5-20.7%), Hungarians (16.6%; 95% CI: 13.1-20.8%), Russians (15.6%; 95% CI: 11.3-21.3%), women living in North (19.2%; 95% CI: 16.5-22.3%), and West regions (23.0%; 95 CI: 18.6-28.0%), and women living in urban areas (20.0%; 95 CI: 18.5-28.0%). hrHPV prevalence rates were lower for the Roma population (7.8%; 95% CI: 4.7-12.5%).

CONCLUSIONS

These hrHPV prevalence rates in a high cervical cancer incidence country provide baseline information for targeted cervical cancer intervention strategies as well as a baseline to measure the impact of hrHPV vaccination in the future.

Association of Human Papillomavirus Genotype 16 Viral Variant and Viral Load with Cervical High-grade Intraepithelial Lesions

Human papillomavirus genotype 16 (HPV16) is by far the genotype most strongly associated with cervical cancer; viral variant and/or viral load of HPV16 could modulate this association. The objective was to determine the association between the viral variant and viral load of HPV16 and the presence of cervical high-grade lesions. This cross-sectional study included all women in whom HPV infection was found by cervical smear during routine gynecologic health checks. Women with single or multiple HPV16 infections (n = 176) were selected for viral variant and viral load analysis. Smear results were classified using the Bethesda system. HPV types were classified according to the International Agency for Research on Cancer. Odds ratios (OR) with their 95% confidence intervals (CI) were estimated by logistic regression, adjusted for age, immigrant status, and coinfection with other high-risk genotypes. No statistically significant associations were found regarding the detected viral variants. A viral load above the median (>1,367.79 copies/cell) was associated with a significant risk of high-grade epithelial lesion or carcinoma, after adjusting for age, immigrant status, coinfections, and viral variant: (adjusted OR 7.89; 95% CI: 2.75-22.68). This relationship showed a statistically significant dose-response pattern after categorizing by viral load tertiles: adjusted OR for a viral load greater than the third tertile was 17.23 (95% CI: 4.20-70.65), with adjusted linear P _trend = 0.001. In patients infected with HPV16, viral load is associated with high-grade intraepithelial lesions or cervical carcinoma. This could be useful as prognostic biomarker of neoplastic progression and as screening for cervical cancer.

Bayesian analysis of baseline risk of CIN2 and ≥CIN3 by HPV genotype in a European referral cohort

Whereas HPV16 and HPV18 have been the focus in current risk-based cervical cancer screening algorithms using HPV genotype information, mounting evidence suggests that oncogenic HPV types such as HPV31, 33, 52 and 58 pose a ≥CIN3 risk equivalent to or greater than that of HPV18, and the combined risk of HPV31 and HPV33 rivals even HPV16 in women above 30 years of age. Here, we evaluate the baseline risk of CIN2 and CIN3 by genotype in a colposcopy referral population from Denmark and Italy. In total, 655 women were enrolled upon a referral to colposcopy after a positive screening sample. All samples were HPV analyzed using Onclarity HPV assay with extended genotyping and combined with the histology outcomes, a Bayesian probability modeling was used to determine the risk per genotype assessed. The combined data for this referral population showed that the ≥CIN2 risk of HPV16 was 69.1%, HPV31 at 63.3%, HPV33/58 at 52.7%, HPV18 at 46.6% and HPV52 at 40.8%. For ≥CIN3, the risks were 44.3%, 38.5%, 36.8%, 30.9% and 16.8% for HPV16, HPV31, HPV18, HPV33/58 and HPV52, respectively, indicating that the baseline risk of disease arising from HPV16 is, not surprisingly, the highest among the oncogenic HPV genotypes. We find that the HPV genotype-specific ≥CIN2 and ≥CIN3 risk-patterns are so distinct that, for example, 35/39/68 and 56/59/66 should be considered only for low intensive follow-up, thereby proposing active use of this information in triage strategies for screening HPV-positive women.

Distinct geographic clustering of oncogenic human papillomaviruses multiple infections in cervical cancers: Results from a worldwide cross-sectional study

Coinfections by multiple Human Papillomaviruses (HPVs) are observed in approximately 6-8% of invasive cervical cancer (ICC) cases worldwide. But neither the presence of persistent HPVs coinfections nor their etiological role in the development of ICC is well understood. Cervical HPVs coinfections have been observed randomly, mostly in women with preneoplastic lesions, and only few studies have globally analyzed ICC cases. Here we explored the HPVs multiple infection patterns in a large worldwide sample of cross-sectional ICC cases. Paraffin-embedded ICC biopsy samples were tested using stringent HPV genotyping. Logistic regression models were used to identify the most likely pairwise HPV types in multiple infections. Multivariate analysis was applied to detect significant HPV coinfection patterns beyond pairwise HPVs comparison. Among 8780 HPV DNA-positive ICC cases worldwide, 6.7% (N = 587) contained multiple HPVs. Pairwise analysis revealed that HPV16|74, HPV31|33, HPV31|44, HPV33|44 and HPV45|70 pairs were significantly more frequently found together in multiple infections compared to any other HPV type combination, which supports the occasional role of Alpha-10 LR-HPVs in cervical cancers. In contrast, HPV16|31, HPV16|45, HPV16|51 and HPV18|HPV45 pairs were significantly less frequently found together than with any other HPV pair combination. Multivariate analysis sustained the results and revealed for the first time a distinct coinfection pattern in African ICCs stemming from the clustering of oncogenic HPV51/35/18/52 coinfections in African women. We suggest that the differential geographic HPVs coinfections clustering observed might be compatible with a specific modulation of the natural history/oncogenic potential of particular HPVs multiple infections and warrant monitoring for post-vaccinated.

Bovine papillomavirus 24: a novel member of the genus Xipapillomavirus detected in the Amazon region

Bovine papillomaviruses (BPVs) have been described as etiologic agents of cutaneous and mucosal papillomas in cattle. In the present study, we describe a new BPV that was detected in a cutaneous papilloma from a cow. Phylogenetic analysis suggests that this virus belong to the genus Xipapillomavirus, and we refer to it here as BPV type 24 (BPV24). Coinfection with members of the genera Epsilonpapillomavirus and Deltapapillomavirus in a cutaneous papilloma from a different animal was also detected, and the full genomes of these viruses were sequenced. Both papillomas were from cattle within Acre State in the Amazon region of Brazil. The data presented here demonstrate the utility of using high-throughput methods to indentify coinfections and allow the characterization of new genomes.

Frequency of Equus caballus papillomavirus in equine aural plaques

Despite the reported association between aural plaques and the presence of Equus caballus papillomavirus (EcPV), there are few data regarding the distribution of viral types in different geographic regions or possible correlations for different papillomaviruses and lesion characteristics. We detected the presence and frequency of EcPV (1-7) DNA in aural plaque biopsies of horses from different regions of Brazil and identified the patterns of these infections or coinfections and their possible association with lesion severity. A total of 108 aural plaque biopsies from horses in the 5 geopolitical regions of Brazil were examined. We performed PCR to detect EcPV DNA in the biopsies. At least 1 type of EcPV was detected in 97% of the samples. EcPV coinfection was observed in 59% of the samples. Compared to the other viruses, EcPV-4 was found at the highest frequency in coinfection (84%) or individually identified (32%). EcPV-2 and -7 were not detected. No significant association was found between lesion characteristics (type and distribution) and either the viral type detected or the presence of coinfection. EcPV is widely distributed in Brazil, both isolated and in coinfection; the viral type does not appear to influence the clinical characteristics of equine aural plaques.

Superinfection Exclusion between Two High-Risk Human Papillomavirus Types during a Coinfection

Superinfection exclusion is a common phenomenon whereby a single cell is unable to be infected by two types of the same pathogen. Superinfection exclusion has been described for various viruses, including vaccinia virus, measles virus, hepatitis C virus, influenza A virus, and human immunodeficiency virus. Additionally, the mechanism of exclusion has been observed at various steps of the viral life cycle, including attachment, entry, viral genomic replication, transcription, and exocytosis. Human papillomavirus (HPV) is the causative agent of cervical cancer. Recent epidemiological studies indicate that up to 50% women who are HPV positive (HPV⁺) are infected with more than one HPV type. However, no mechanism of superinfection exclusion has ever been identified for HPV. Here, we show that superinfection exclusion exists during a HPV coinfection and that it occurs on the cell surface during the attachment/entry phase of the viral life cycle. Additionally, we are able to show that the minor capsid protein L2 plays a role in this exclusion. This study shows, for the first time, that superinfection exclusion occurs during HPV coinfections and describes a potential molecular mechanism through which it occurs.IMPORTANCE Superinfection exclusion is a phenomenon whereby one cell is unable to be infected by multiple related pathogens. This phenomenon has been described for many viruses and has been shown to occur at various points in the viral life cycle. HPV is the causative agent of cervical cancer and is involved in other anogenital and oropharyngeal cancers. Recent epidemiological research has shown that up to 50% of HPV-positive individuals harbor more than one type of HPV. We investigated the interaction between two high-risk HPV types, HPV16 and HPV18, during a coinfection. We present data showing that HPV16 is able to block or exclude HPV18 on the cell surface during a coinfection. This exclusion is due in part to differences in the HPV minor capsid protein L2. This report provides, for the first time, evidence of superinfection exclusion for HPV and leads to a better understanding of the complex interactions between multiple HPV types during coinfections.

Prevalence of human papillomavirus infection among women from quilombo communities in northeastern Brazil

BACKGROUND

Human papillomavirus (HPV) is a member of the Papillomaviridae family. The prevalence of HPV genotypes may vary according to the region and the population studied. Quilombo communities are ethnic and racial groups with difficult access to health services compared to the general population in Brazil. The aim of this study was to identify specific HPV types correlating with sociodemographic/behavioral characteristics and cervical smear cytological abnormalities in Quilombola women.

METHODS

This cross-sectional study included 395 Quilombola women users of the Unified Health System of the Municipalities of Maranhão for the screening of cervical cancer. The samples were analyzed for the presence of cytological abnormalities by conventional methods and tested for 37 HPV genotypes using polymerase chain reaction with primers PGMY09/11 followed by reverse line blot hybridization performed with the Linear Array HPV Genotyping Test kit by Roche Molecular System®. The association between HPV types and cytological diagnosis was investigated according to the different age groups.

RESULTS

HPV infection was detected in 12.6% (50/395) of the women. Infections by high-risk HPV types were more frequent. Genotypes 68 (26.0%); 58 and 52 (20.0%); 31 (10.0%) and 62 (8.0%) were the most prevalent. The highest prevalence (42.0%) of HPV infection occurred in women diagnosed with high-grade squamous intraepithelial lesion. There was a statistically significant association between HPV infection and the detection of cytological abnormalities in all age groups except in women over 60 years. There was a statistically significant association between the municipality of origin and the number of partners with HPV infection.

CONCLUSIONS

It is important to incorporate new cervical cancer screening techniques incorporating the cervical-vaginal cytology. For further studies, it is necessary to determine the level of knowledge of Quilombola population on health-related issues including HPV infection and cervical cancer. This will contribute to the continuous improvement of healthcare coverage among the population and enhance the implementation of cancer care in the state of Maranhão.

Human papillomavirus genotypes 68 and 58 are the most prevalent genotypes in women from quilombo communities in the state of Maranhão, Brazil

OBJECTIVES

To determine the frequency of human papillomavirus (HPV) types and behavioral characteristics related to cytological abnormalities in women descendants of slaves, who live in isolated communities known as quilombos in the state of Maranhão, Brazil.

METHODS

Cervicovaginal specimens of 353 women were analyzed by conventional cytology and genotyping. HPV detection and genotyping was performed using a linear array HPV genotyping test kit. Behavioral factors and their association with cytological abnormalities were analyzed, as well as the association between cytological abnormalities and HPV infection.

RESULTS

The frequency of HPV infection was 13%, and infection with high-risk HPV types was more frequent than with low-risk types (10.2% vs. 2.8%). The most prevalent genotypes were HPV 68 (3.1%) and HPV 58 (2.6%). HPV-positive women were 6.5 times more likely than HPV-negative women to be diagnosed with cytological abnormalities. There was a significant association between HPV infection and the presence of cytological abnormalities in women 31-40 years of age and in women 51-60 years of age.

CONCLUSIONS

A distinct profile of high-risk HPV genotypes was detected, with predominance of types 68 and 58. It is possible that the results of the present study are due to specific characteristics of the population, which is geographically isolated and maintains conservative sexual habits.

How many papillomavirus species can go undetected in papilloma lesions?

A co-infection comprising to at least seven papillomavirus (PV) types was detected by next generation sequencing (NGS) of randomly primed rolling circle amplification (RCA) products of a bovine (Bos taurus) papilloma lesion from the Brazilian Amazon region. Six putative new PV types that could not be detected by commonly used PCR protocols were identified. Their overall L1 nucleotide identities were less than 90% compared to described PV species and types. L1 nucleotide BLAST sequence hits showed that each new type was related to Beta, Gamma, Dyokappa, Dyoeta, and Xipapillomavirus, as well as two likely new unclassified genera. Our results show that the employment of NGS is relevant to the detection and characterization of distantly related PV and is of major importance in co-infection studies. This knowledge will help us understand the biology and pathogenesis of PV, as well as contribute to disease control. Moreover, we can also conclude that there are many unknown circulating PVs.

Cross-reactivity profiles of hybrid capture II, cobas, and APTIMA human papillomavirus assays: split-sample study

BACKGROUND

High-risk Human Papillomavirus (HPV) testing is replacing cytology in cervical cancer screening as it is more sensitive for preinvasive cervical lesions. However, the bottleneck of HPV testing is the many false positive test results (positive tests without cervical lesions). Here, we evaluated to what extent these can be explained by cross-reactivity, i.e. positive test results without evidence of high-risk HPV genotypes. The patterns of cross-reactivity have been thoroughly studied for hybrid capture II (HC2) but not yet for newer HPV assays although the manufacturers claimed no or limited frequency of cross-reactivity. In this independent study we evaluated the frequency of cross-reactivity for HC2, cobas, and APTIMA assays.

METHODS

Consecutive routine cervical screening samples from 5022 Danish women, including 2859 from women attending primary screening, were tested with the three evaluated DNA and mRNA HPV assays. Genotyping was undertaken using CLART HPV2 assay, individually detecting 35 genotypes. The presence or absence of cervical lesions was determined with histological examinations; women with abnormal cytology were managed as per routine recommendations; those with normal cytology and positive high-risk HPV test results were invited for repeated testing in 18 months.

RESULTS

Cross-reactivity to low-risk genotypes was detected in 109 (2.2 %) out of 5022 samples on HC2, 62 (1.2 %) on cobas, and 35 (0.7 %) on APTIMA with only 10 of the samples cross-reacting on all 3 assays. None of the 35 genotypes was detected in 49 (1.0 %), 162 (3.2 %), and 56 (1.1 %) samples, respectively. In primary screening at age 30 to 65 years (n = 2859), samples of 72 (25 %) out of 289 with high-risk infections on HC2 and < CIN2 histology were due to cross-reactivity. On cobas, this was 106 (26 %) out of 415, and on APTIMA 48 (21 %) out of 224.

CONCLUSIONS

Despite manufacturer claims, all three assays showed cross-reactivity. In primary cervical screening at age ≥30 years, cross-reactivity accounted for about one quarter of false positive test results regardless of the assay. Cross-reactivity should be addressed in EU tenders, as this primarily technical shortcoming imposes additional costs on the screening programmes.

The BD Onclarity HPV Assay on Samples Collected in SurePath Medium Meets the International Guidelines for Human Papillomavirus Test Requirements for Cervical Screening

This study describes a validation of the BD Onclarity HPV (Onclarity) assay using the international guidelines for HPV test requirements for cervical cancer screening of women 30 years old and older using Danish SurePath screening samples. The clinical specificity (0.90, 95% confidence interval [CI] = 0.88 to 0.91) and sensitivity (0.97, 95% CI = 0.87 to 1.0) of the Onclarity assay were shown to be not inferior to the reference assay (specificity, 0.90 [95% CI = 0.88 to 0.92]; sensitivity, 0.98 [95% CI = 0.91 to 1.0]). The intralaboratory reproducibility of Onclarity was 97%, with a lower confidence bound of 96% (kappa value, 0.93). The interlaboratory agreement was 97%, with a lower confidence bound of 95% (kappa value, 0.92). The BD Onclarity HPV assay fulfills all the international guidelines for a new HPV test to be used in primarily screening. This is the first clinical validation of a new HPV assay using SurePath screening samples, and thus the Onclarity HPV assay is the first HPV assay to hold an international validation for both SurePath and ThinPrep.

Evidence for contribution of common genetic variants within chromosome 8p21.2-8p21.1 to restricted and repetitive behaviors in autism spectrum disorders

BACKGROUND

Restricted and Repetitive Behaviors (RRB), one of the core symptom categories for Autism Spectrum Disorders (ASD), comprises heterogeneous groups of behaviors. Previous research indicates that there are two or more factors (subcategories) within the RRB domain. In an effort to identify common variants associated with RRB, we have carried out a genome-wide association study (GWAS) using the Autism Genetic Resource Exchange (AGRE) dataset (n = 1,335, all ASD probands of European ancestry) for each identified RRB subcategory, while allowing for comparisons of associated single nucleotide polymorphisms (SNPs) with associated SNPs in the same set of probands analyzed using all the RRB subcategories as phenotypes in a multivariate linear mixed model. The top ranked SNPs were then explored in an independent dataset.

RESULTS

Using principal component analysis of item scores obtained from Autism Diagnostic Interview-Revised (ADI-R), two distinct subcategories within Restricted and Repetitive Behaviors were identified: Repetitive Sensory Motor (RSM) and Insistence on Sameness (IS). Quantitative RSM and IS scores were subsequently used as phenotypes in a GWAS using the AGRE ASD cohort. Although no associated SNPs with genome-wide significance (P < 5.0E-08) were detected when RSM or IS were analyzed independently, three SNPs approached genome-wide significance when RSM and IS were considered together using multivariate association analysis. These included the top IS-associated SNP, rs62503729 (P-value = 6.48E-08), which is located within chromosome 8p21.2-8p21.1, a locus previously linked to schizophrenia. Notably, all of the most significantly associated SNPs are located in close proximity to STMN4 and PTK2B, genes previously shown to function in neuron development. In addition, several of the top-ranked SNPs showed correlations with STMN4 mRNA expression in adult CEU (Caucasian and European descent) human prefrontal cortex. However, the association signals within chromosome 8p21.2-8p21.1 failed to replicate in an independent sample of 2,588 ASD probands; the insufficient sample size and between-study heterogeneity are possible explanations for the non-replication.

CONCLUSIONS

Our analysis indicates that RRB in ASD can be represented by two distinct subcategories: RSM and IS. Subsequent univariate and multivariate genome-wide association studies of these RRB subcategories enabled the detection of associated SNPs at 8p21.2-8p21.1. Although these results did not replicate in an independent ASD dataset, genomic features of this region and pathway analysis suggest that common variants in 8p21.2-8p21.1 may contribute to RRB, particularly IS. Together, these observations warrant future studies to elucidate the possible contributions of common variants in 8p21.2-8p21.1 to the etiology of RSM and IS in ASD.

Human Papillomavirus Assays and Cytology in Primary Cervical Screening of Women Aged 30 Years and Above

In women aged ≥ 30 years, Human Papillomavirus testing will replace cytology for primary cervical screening. We compared Hybrid Capture 2 (HC2), cobas, CLART, and APTIMA HPV assays with cytology on 2869 SurePath samples from women undergoing routine screening at 30-65 years in Copenhagen, Denmark. Women with cytological abnormalities were managed according to routine recommendations, with 92% completeness. Those with cytology-normal/HPV-positive samples (on any of the four assays) were invited for repeated cytology and HPV testing in 1.5 year, and 58% had additional testing. HPV testing detected more ≥ CIN3 than cytology (HC2: 35, cobas, CLART: 37, APTIMA: 34, cytology: 31), although statistically the differences were not significant. Cobas and CLART detected significantly more ≥ CIN2 than cytology (cobas, CLART: 49, cytology: 39). The proportion of women with false-positive test results (positive test results without ≥ CIN3) varied between 3.3% with cytology and 14.9% with cobas. All HPV assays led to significantly more false-positive tests, whereas compared to HC2 cobas and CLART were associated with a significantly higher and APTIMA with a significantly lower proportion. Detection of CIN1 was particularly increased for the three DNA assays. With APTIMA combined with cytological triage, about 20% more women were referred for colposcopy than with cytology screening. With the three DNA assays, the increase was ≥ 50%. The number of women with repeated testing was twice as high with APTIMA and almost five times as high with cobas compared to cytology. To our knowledge, Horizon was the only study set in routine practice that compared more than two HPV assays in the same women while also ascertaining the histological status of women with normal cytology/HPV-positive test results. HPV-based screening of Danish women aged 30-65 detected more high-grade CIN but decreased the screening specificity, and increased the demand for additional testing.

Prevalence of type-specific HPV among female university students from northern Brazil

Background

Human papillomavirus (HPV) infection is associated with cervical cancer, the most frequent cancer in women from northern Brazil. Assessment of the short-term impact of HPV vaccination depends on the availability of data on the prevalence of type-specific HPV in young women in the pre-immunization period, although these data are currently unavailable for the study region. The aim of this study was to estimate the distribution of all mucosal HPV genotypes, including low- and high-risk HPV types, in unvaccinated college students from northern Brazil.

Findings

Specimens were collected from 265 university students during routine cervical cancer screening. The HPV DNA was assessed by Polymerase Chain Reaction and positive samples were genotyped by Restriction Fragment Length Polymorphism. Most students (85.7 %) had normal cytological results. The prevalence of HPV was 25.3 % (67/265), with a high frequency of multiple infections and non-vaccine high-risk HPV genotypes. The most prevalent type was HPV-61 (5.3 %), followed by types 82, 16, 59, and 6. Multiple infections were associated with high-risk and possibly high-risk HPVs.

Conclusions

We demonstrated a high prevalence of HPV infection in university students from northern Brazil. Vaccine high-risk types were relatively rare, emphasizing the predominance of carcinogenic genotypes that are not prevented by the currently available vaccines. Our study highlights the need to reinforce cytological screening in women from northern Brazil, and promote the early diagnosis and treatment of the precancerous lesions associated with cervical cancer.

Attributing oncogenic human papillomavirus genotypes to high-grade cervical neoplasia: which type causes the lesion?

Human papillomavirus (HPV) is found in most women with high-grade cervical intraepithelial neoplasia (CIN) 2/3 in cervical cytology and biopsies. Multiple high-risk HPV (hrHPV) genotypes are present in 15% to 50% of cytology samples. We have shown by laser-capture microscopy (LCM)-polymerase chain reaction (PCR) that each lesion is associated with a single hrHPV type. Attribution of hrHPV types to CIN2/3 is important to understand the oncogenic role of different types and the limitations of cytologic typing. We studied hrHPV genotypes in 257 women with histologic CIN2/3 referred on the basis of abnormal cytology. HPV typing was done on cytology and CIN2/3 biopsies. If the whole-tissue section of the biopsy was positive for multiple hrHPV types, LCM-PCR was performed. We found 181 (70%) single and 71 (28%) multiple hrHPV infections in cytology, with 5 (2%) cases HPV-positive only on whole-tissue section PCR. Of cases with multiple cytologic hrHPV infections, 47/71 (66%) showed a single type in CIN2/3 lesions. In total, in 232 of 257 (90%) women with CIN2/3, a single hrHPV type caused CIN2/3. One was nonattributable on the LCM level. The remaining 24 women had 2 or more contiguous or separated lesions, each associated with a single hrHPV infection. The probability of HPV16 being present in CIN2/3, if detected in cytology, was 0.96 (95% confidence interval=0.90-0.98). LCM-PCR confirms that only 9% of histologic CIN2/3 is associated with multiple hrHPV types, much less than cytology would indicate, and each lesion was associated with a single hrHPV infection.

Impact of coverage-dependent marginal costs on optimal HPV vaccination strategies

The effectiveness of vaccinating males against the human papillomavirus (HPV) remains a controversial subject. Many existing studies conclude that increasing female coverage is more effective than diverting resources into male vaccination. Recently, several empirical studies on HPV immunization have been published, providing evidence of the fact that marginal vaccination costs increase with coverage. In this study, we use a stochastic agent-based modeling framework to revisit the male vaccination debate in light of these new findings. Within this framework, we assess the impact of coverage-dependent marginal costs of vaccine distribution on optimal immunization strategies against HPV. Focusing on the two scenarios of ongoing and new vaccination programs, we analyze different resource allocation policies and their effects on overall disease burden. Our results suggest that if the costs associated with vaccinating males are relatively close to those associated with vaccinating females, then coverage-dependent, increasing marginal costs may favor vaccination strategies that entail immunization of both genders. In particular, this study emphasizes the necessity for further empirical research on the nature of coverage-dependent vaccination costs.

HPV prevalence and genotype distribution in a population-based split-sample study of well-screened women using CLART HPV2 human papillomavirus genotype microarray system

Background

Human papillomavirus (HPV) genotyping assays are becoming increasingly attractive for use in mass screening, as they offer a possibility to integrate HPV screening with HPV vaccine monitoring, thereby generating a synergy between the two main modes of cervical cancer prevention. The Genomica CLART HPV2 assay is a semi-automated PCR-based microarray assay detecting 35 high-risk and low-risk HPV genotypes. However, few reports have described this assay in cervical screening.

An aim of the present study, Horizon, was to assess the prevalence of high-risk HPV infections in Copenhagen, Denmark, an area with a high background risk of cervical cancer where women aged 23-65 years are targeted for organized screening.

Methods

Material from 5,068 SurePath samples of women participating in routine screening and clinical follow-up of cervical abnormalities was tested using liquid based cytology, CLART HPV2 and Hybrid Capture 2 (HC2).

Results

At least one of the 35 defined genotypes was detected by CLART in 1,896 (37%) samples. The most frequent high-risk genotypes were HPV 16 (7%), HPV 52 (5%), and HPV 31 (4%). The most frequent low-risk genotypes were HPV 53 (5%), HPV 61 (4%), and HPV 66 (3%). Among 4,793 women targeted by the screening program (23-65 years), 1,166 (24%) tested positive for one or more of the 13 high-risk genotypes. This proportion decreased from 40% at age 23-29 years to 10% at age 60-65 years. On HC2, 1,035 (20%) samples were positive for any high-risk and thus CLART showed a higher analytical sensitivity for 13 high-risk HPV genotypes than HC2, and this was found in all age-groups and in women normal cytology.

Conclusions

CLART performed well with a positive reproducibility for high-risk genotypes of 86%, and a negative reproducibility of 97%. This report furthermore updates the genotype distribution in Denmark prior to the inclusion of the HPV-vaccinated cohorts into the screening program, and as such represents a valuable baseline for future vaccine impact assessment.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-413) contains supplementary material, which is available to authorized users.

Impact of human papillomavirus coinfections on the risk of high-grade squamous intraepithelial lesion and cervical cancer

OBJECTIVE

The molecular and epidemiologic effect of human papillomavirus (HPV) coinfections in the risk of developing cervical cancer is yet unclear. The aim of this study was to determine the frequency HPV coinfections at different stages of cervical lesions in the development of cervical cancer and the impact of HPV specific type interactions on high-grade squamous intraepithelial lesions (HSIL) and invasive cervical cancer (ICC) risk.

METHODS

HPV testing was performed in 931 cervical samples diagnosed as: negative for intraepithelial lesion or malignancy (NILM); low-grade squamous intraepithelial lesion (LSIL); HSIL; and ICC. For HPV detection and typing two sets of primers from the L1 region were used in the polymerase chain reaction method (PCR) (MY09/MY11/HMB01 and L1C1/L1C2.1/L1C2.2) and HPV type was determined by PCR product sequence. To look for multiple HPV infections, the E6 nested multiplex PCR method was performed in all DNA samples. Odds ratios were calculated as indexes of the strength of the association between the sample category (LSIL/NILM or ICC/HSIL) and the presence of a given viral combination.

RESULTS

In HPV positive samples, coinfections are as common in ICC/HSIL as in LSIL/NILM (47.12% and 40.17%, respectively). There is an increased risk to ICC/HSIL when multiple high-risk HPV types are present. The coinfection of HPV68 with HPV16 increases the risk of ICC/HSIL (OR=14.54, P=0.012, after multivariate adjustment), related to the presence of HPV16 or HPV68 alone.

CONCLUSIONS

These results sustain that specific HPV coinfections confer an increased risk to develop ICC/HSIL.

Cervical cytology and multiple type HPV infection: a study of 8182 women ages 31-65

OBJECTIVE

The aim of this study is to determine the rates of single and multiple type human papillomavirus (HPV) infection in women in the United States ages 31-65 with known cervical cytology results.

METHODS

Type-specific HPV analyses were conducted using the first samples of women who had HPV typing performed by Access Genetics as part of cervical cancer screening between July 2007 and May 2011. Women 31-65years at testing with associated abnormal cytology results were included. The odds of abnormal cytology (compared to normal results) for multiple vs. single HPV infections were calculated for each cytology sub-type and odds ratios (OR) and 95% confidence intervals (CI) are reported.

RESULTS

The analysis included 8182 women. The majority (67.7%) had ASCUS cervical cytology. A total of 329 (4.0%) were positive for 2 or more HPV types. For all cervical cytology subtypes considered (ASCUS, ASCUS-H, LSIL or HSIL), women with multiple type infections were more likely to have abnormal cytology (compared to normal cytology) with the highest OR associated with HSIL (OR 1.81 (1.26-2.60)). When analyzing HPV type 16 alone, women with multiple type infections were more likely to have abnormal cytology, with the highest OR associated with HSIL cytology (OR 2.98 (1.57-5.64)). Few women had HPV type 18 infections and no results reached statistical significance. Results based on phylogenic family organization focusing on the alpha 9 phylogenic family showed similar results as HPV type 16.

CONCLUSIONS

Women ages 31-65 with multiple type HPV infections were more likely to have abnormal cytology than those with single HPV type infections.

Human papillomavirus community in healthy persons, defined by metagenomics analysis of human microbiome project shotgun sequencing data sets

Human papillomavirus (HPV) causes a number of neoplastic diseases in humans. Here, we show a complex normal HPV community in a cohort of 103 healthy human subjects, by metagenomics analysis of the shotgun sequencing data generated from the NIH Human Microbiome Project. The overall HPV prevalence was 68.9% and was highest in the skin (61.3%), followed by the vagina (41.5%), mouth (30%), and gut (17.3%). Of the 109 HPV types as well as additional unclassified types detected, most were undetectable by the widely used commercial kits targeting the vaginal/cervical HPV types. These HPVs likely represent true HPV infections rather than transitory exposure because of strong organ tropism and persistence of the same HPV types in repeat samples. Coexistence of multiple HPV types was found in 48.1% of the HPV-positive samples. Networking between HPV types, cooccurrence or exclusion, was detected in vaginal and skin samples. Large contigs assembled from short HPV reads were obtained from several samples, confirming their genuine HPV origin. This first large-scale survey of HPV using a shotgun sequencing approach yielded a comprehensive map of HPV infections among different body sites of healthy human subjects.

IMPORTANCE

This nonbiased survey indicates that the HPV community in healthy humans is much more complex than previously defined by widely used kits that are target selective for only a few high- and low-risk HPV types for cervical cancer. The importance of nononcogenic viruses in a mixed HPV infection could be for stimulating or inhibiting a coexisting oncogenic virus via viral interference or immune cross-reaction. Knowledge gained from this study will be helpful to guide the designing of epidemiological and clinical studies in the future to determine the impact of nononcogenic HPV types on the outcome of HPV infections.

Patterns of human papillomavirus types in multiple infections: an analysis in women and men of the high throughput human papillomavirus monitoring study

Background

To evaluate the pattern of co-infection of human papillomavirus (HPV) types in both sexes in Sweden.

Methods

Cell samples from genital swabs, first-void urine, and genital swabs immersed in first-void urine were collected in the present cross-sectional High Throughput HPV Monitoring study. Overall, 31,717 samples from women and 9,949 from men (mean age 25) were tested for 16 HPV types using mass spectrometry. Multilevel logistic regression was used to estimate the expected number of multiple infections with specific HPV types, adjusted for age, type of sample, and accounting for correlations between HPV types due to unobserved risk factors using sample-level random effects. Bonferroni correction was used to allow for multiple comparisons (120).

Results

Observed-to-expected ratio for any multiple infections was slightly above unity in both sexes, but, for most 2-type combinations, there was no evidence of significant departure from expected numbers. HPV6/18 was found more often and HPV51/68 and 6/68 less often than expected. However, HPV68 tended to be generally underrepresented in co-infections, suggesting a sub-optimal performance of our testing method for this HPV type.

Conclusions

We found no evidence for positive or negative clustering between HPV types included in the current prophylactic vaccines and other untargeted oncogenic types, in either sex.

High HPV-51 prevalence in invasive cervical cancers: results of a pre-immunization survey in North Sardinia, Italy

Background

Human Papilloma virus (HPV) is recognized as the etiological agent of benign and malignant ano-genital lesions. The most prevalent genotypes associated with cervical carcinoma are HPV-16 and -18 worldwide. However, recent studies have emphasized the role of other genotypes, such as HPV-51, in the pathogenesis of cervical dysplasia. The aim of the study was to estimate the burden of HPV-51 infection in invasive cervical malignant lesions in Northern Sardinia, Italy.

Methods/Principal Findings

An observational, retrospective, prevalence, mono-center study was carried out to evaluate the presence of HPV genotypes in tissues biopsies of cervical lesions (CIN-1, CIN-2, CIN-3 and invasive carcinoma) gathered from 1996 to 2009. Biological samples were collected from women admitted consecutively to a tertiary university hospital situated in Sassari, Italy. Molecular methods were used to identify 28 oncogenic HPV types. A total of 155 formalin-fixed and paraffin-embedded cervical tissue samples were analyzed. Approximately half of the cervical lesions were classified as invasive carcinoma. HPV-DNA was detected in 71% of the samples, with a higher frequency (100%) in those categorized as invasive neoplasia. Mono- or co-infections were demonstrated in 45.8% and 25.8% of the cervical samples, respectively. Overall, the most prevalent HPV types were -16 (49%) and -51 (19.4%), with an increased frequency of detection associated with the severity of the cervical lesions.

Conclusions/Significance

This survey highlights for the first time the relevant role of HPV-51 infection in the pathogenesis of invasive cervical cancer prior to the introduction of a vaccination program. Although a selection bias could have influenced the results, other recent studies have described the impact of HPV-51. This remarkable epidemiological element should be carefully evaluated, particularly in the view of opting for preventive vaccines, whose cross-protection patterns determine their efficacy in protecting against infection from HPV types that are not included in the vaccine itself.