Human Papillomavirus Type Research Articles

Human Papillomaviruses (HPVs)—A Review for Diagnosis and Vaccination

Human papillomaviruses (HPVs) are a group of more than 150 related viruses. They are called papillomaviruses because some of them cause papillomas, which are more commonly known as warts. Some types of HPV only grow in skin, while others grow in mucous membranes such as the mouth, throat, or vagina. All types of HPV are spread by contact (touch). More than 40 types of HPV can be passed on through sexual contact. Most sexually active people are infected with one or more of these HPV types at some point in their lives. At least a dozen of these HPV types are known to cause cancer. While HPV infections are very common, cancer caused by HPV is not. Most people infected with HPV will not develop cancer-related to the infection. However, some people with long-lasting infections of high-risk HPV types are at risk of developing cancer. HPV infections of the mucous membranes can cause genital warts, but they usually have no symptoms. There are no effective medicines or other treatments for HPV, other than removing or destroying cells that are known to be infected. But in most people, the body’s immune system controls the HPV infection or gets rid of it over time. To learn more, see HPV and HPV Testing.

Assessing the feasibility of a multimodal liquid biopsy for the diagnosis of HPV-associated oropharyngeal squamous cell carcinoma.

In this feasibility study, we explored the combined use of circulating tumor human papillomavirus (HPV) DNA (ctHPVDNA) and HPV serology as diagnostic tests for HPV-associated oropharyngeal squamous cell carcinoma (OPSCC). Among patients with research-banked serum or plasma at diagnosis, IgG antibodies to oncoproteins from HPV types 16, 18, 31, 33, 35, 45, 52, and 58 were detected with multiplex serology. Positivity for HPV 16 was defined based on detection of combinations of anti-E6, E1, E2, and E7 and for other high-risk types on detection of anti-E6 and anti-E7. Circulating tumor HPV DNA was detected by custom digital droplet polymerase chain reaction (ddPCR) assays for HPV types 16, 18, 33, 35, and 45. p16 immunohistochemistry and high-risk HPV RNA in situ hybridization (ISH) using a cocktail of 18 high-risk HPV types were performed on tissue. Of 75 patients, 67 (89.3%) were HPV-associated (p16 and HPV RNA ISH positive) and 8 (10.7%) were HPV-independent. All 8 HPV-independent patients were seronegative and negative for ctHPVDNA (100% specificity). Serology was positive in 53 (79.1%) of 67 HPV-associated patients, while ddPCR was positive for ctHPVDNA in 59 (88.6%) of 67 HPV-associated patients. Requiring both tests to be positive resulted in a sensitivity of 50 (74.6%) of 67 while combining assays (either positive) improved sensitivity to 62 (92.6%) of 67. Compared to HPV RNA ISH, HPV serology and ctHPVDNA are sensitive and highly specific biomarkers for HPV-associated OPSCC at the time of presentation.

Human papillomavirus type 16 E7 promotes cell viability and migration in cervical cancer by regulating the miR-23a/HOXC8 axis

Background Human papillomavirus (HPV) is a risk factor for the occurrence of cervical cancer (CC). Here, we aimed to explore the role of HPV16 in CC and identify the underlying mechanism. Methods The expression of miR-23a, HPV16 E6/E7 and homeobox C8 (HOXC8) was measured by quantitative real-time PCR or western blot. Cell viability and migration were evaluated using cell counting kit-8, Transwell and wound healing assays. The targeting relationship between miR-23a and HOXC8 was revealed by dual-luciferase reporter assay. Results miR-23a was downregulated in HPV16-positive (HPV16+) CC tissues and HPV16+ and HPV18+ cells. Additionally, E6/E7 expression was increased in CC cells. Then, we found that E7, rather than E6, positively regulated miR-23a expression. miR-23a suppressed cell viability and migration, whereas E7 overexpression abrogated this suppression. miR-23a targeted HOXC8, which reversed miR-23a-mediated cell viability and migration. Conclusions HPV16 E7-mediated miR-23a suppressed CC cell viability and migration by targeting HOXC8, suggesting a novel mechanism of HPV-induced CC.

Comparison of nylon-flocked swabs and cotton swabs in the detection of human papillomavirus infection in men.

Human papillomavirus (HPV) is an oncogenic virus and the commonest sexually transmitted pathogen worldwide. Appropriate sampling is an important factor in infection management. This study aimed to compare the efficacy of cotton swabs (CS) and nylon-flocked swabs (NFS) in sampling for HPV-DNA PCR testing in male patients with genital warts. The study included men with genital warts who presented to the urology outpatient clinic of Antalya Medical Park Hospital. Before wart treatment, multisite sampling of the penis and genital area was performed separately with CS and NFS. The samples were analyzed for HPV-DNA using real-time PCR. The study included 45 men with a mean age of 32.1 ± 8.6years. At least one HPV type was detected in all 45 patients with NFS sampling and 44 patients with CS sampling (total HPV types detected: 106 and 84, respectively). NFS sampling detected 52 high-risk HPV types in 37 of the 45 patients, while CS sampling detected 37 high-risk types in 19 patients (p = 0.029). NFS sampling also detected a total of 54 low-risk HPV types in all 45 patients, versus 47 low-risk HPV types in 41 patients with CS sampling. Multiple HPV types were detected in 30 patients with NFS and 17 patients with CS (p = 0.001). NFS were more effective than CS for HPV-DNA testing in men with genital warts. NFS were superior to CS in detecting multiple-type HPV infection and high-risk HPV types. The use of NFS should be recommended for HPV-DNA PCR testing in men.

Feasibility and Acceptability of Self-sampling for Human Papillomavirus DNA Testing Among Asymptomatic Women in Rural Delta State, Nigeria

Background: Self-sampling and human papillomavirus (HPV) DNA testing can be vital tools in cervical cancer screening for hard-to-reach women with limited access to health care in sub-Saharan Africa. This study explored the feasibility and acceptability of self-sampling for HPV testing among asymptomatic women in Orhuwhorun community in Delta State. Methods: This was a cross-sectional study of 230 women aged between 30 - 65years, enrolled by a multi-stage sampling method. Recruited women were asked to provide self-collected vaginal samples between May and June, 2021. HPV detection and genotyping was done using 21 HPV Geno-Array Diagnostic kit. Participants were asked to complete questionnaires after self-sampling to point out their experiences and acceptability of HPV self-sampling. Results: An excellent feasibility of self-sampling (95.2%) was observed. The acceptability rate of self-sampling was 93.0%, and 99.6% (229/230) of the participants were confident that they used the device correctly. The quality of self-sampling was satisfactory in 100% of the samples; 21.1% (48/228) of the samples were positive for HPV, including 12.3% (28/228) with high-risk HPV types,2.6% (6/228) with probable high risk HPV types and 1.8% (4/228)with low-risk HPV types. Multiple HPV infection occurred in 10 cases (4.4%). Conclusion: This study indicates that self-sampling is a feasible and acceptable approach for cervical cancer screening among women in rural Delta State. Thus, the government should consider self-sampling as a valuable strategy in implementing national cancer screening programme.

Codon usage bias of human papillomavirus type 33 and 58: A comprehensive analysis.

Cervical cancer is closely linked to specific strains of human papillomavirus (HPV), notably HPV-33 and HPV-58, which exhibit a significant prevalence among women in China. Nevertheless, the codon usage bias in HPV-33 and HPV-58 is not well comprehended. The objective of this research is to analyze the codon usage patterns HPV-33 and HPV-58, pinpoint the primary factors that influence codon preference. The overall preference for codon usage in two HPV genotypes is not significant. Both HPV genotypes exhibit a preference for codons that end with A/U. The GC3 content for HPV-33 is 25.43% ± 0.35%, and for HPV-58, it is 29.44% ± 0.57%. Out of the 26 favored codons in HPV-33 and HPV-58 (relative synonymous codon usage (RSCU) > 1), 25 conclude with A/U. Principal component analysis (PCA) shows a tight clustering of the entire genome sequences of HPV-33 and HPV-58, suggesting a similarity in their RSCU preferences. Moreover, an examination of dinucleotide abundance indicated that translation selection influenced the development of a distinctive dinucleotide usage pattern in HPV-33 and HPV-58. Additionally, a combined analysis involving an effective number of codons plot, parity rule 2, and neutrality analysis demonstrated that, for HPV-33 and HPV-58, the primary determinant influencing codon usage preference is natural selection. HPV-33 and HPV-58 exhibit a restricted set of favored codons in common with humans, potentially mitigating competition for translation resources. Our discoveries could provide valuable perspectives on the evolutionary patterns and codon usage preferences of HPV-33 and HPV-58 viruses, contributing to the development and application of relevant HPV subtype vaccines.

Improved detection of low-frequency within-host variants from deep sequencing: A case study with human papillomavirus.

High-coverage sequencing allows the study of variants occurring at low frequencies within samples, but is susceptible to false-positives caused by sequencing error. Ion Torrent has a very low single nucleotide variant (SNV) error rate and has been employed for the majority of human papillomavirus (HPV) whole genome sequences. However, benchmarking of intrahost SNVs (iSNVs) has been challenging, partly due to limitations imposed by the HPV life cycle. We address this problem by deep sequencing three replicates for each of 31 samples of HPV type 18 (HPV18). Errors, defined as iSNVs observed in only one of three replicates, are dominated by C→T (G→A) changes, independently of trinucleotide context. True iSNVs, defined as those observed in all three replicates, instead show a more diverse SNV type distribution, with particularly elevated C→T rates in CCG context (CCG→CTG; CGG→CAG) and C→A rates in ACG context (ACG→AAG; CGT→CTT). Characterization of true iSNVs allowed us to develop two methods for detecting true variants: (1) VCFgenie, a dynamic binomial filtering tool which uses each variant's allele count and coverage instead of fixed frequency cut-offs; and (2) a machine learning binary classifier which trains eXtreme Gradient Boosting models on variant features such as quality and trinucleotide context. Each approach outperforms fixed-cut-off filtering of iSNVs, and performance is enhanced when both are used together. Our results provide improved methods for identifying true iSNVs in within-host applications across sequencing platforms, specifically using HPV18 as a case study.

A ProTide of AZT Shows Activity Against Human Papillomaviruses.

Infection by human papillomaviruses (HPV) can cause warts and tumors. So far, no small molecule antiviral has been approved for the treatment of infections with this DNA virus, although preclinical studies show activity for nucleosidic compounds, such as 9-(2-phosphonylmethoxy)ethylguanine (PMEG) or cidofovir. This prompted us to test new prodrug versions of the nucleoside analog 3'-azido-2',3'-dideoxythymidine (AZT), known to be active against reverse transcriptases and approved for the treatment of HIV. Here we report the synthesis of an ethylbutyl alaninyl ester phosphosphoramidate prodrug of AZT, dubbed AZAEB, and its activity against HPV, a target not known to be sensitive to AZT. A methyl ester derivative was found to be inactive against this and three other DNA viruses, while the phosphoramidate prodrug AZAEB showed a modest inhibitory effect against HPV types 6, 11, 18 and 31. Our results open up new avenues of study for the treatment of diseases caused by members of the papillomaviridae family.

Single-tube four-target lateral flow assay detects human papillomavirus types associated with majority of cervical cancers

Isothermal nucleic acid amplification methods have many advantages for use at the point of care. However, there is a lack of multiplexed isothermal amplification tests to detect multiple targets in a single reaction, which would be valuable for many diseases, such as infection with high-risk human papillomavirus (hrHPV). In this study, we developed a multiplexed loop-mediated isothermal amplification (LAMP) reaction to detect the three most common hrHPV types that cause cervical cancer (HPV16, HPV18, and HPV45) and a cellular control for sample adequacy. First, we characterized the assay limit of detection (LOD) in a real-time reaction with fluorescence readout; after 30 min of amplification the LOD was 100, 10, and 10 copies/reaction of HPV16, HPV18, and HPV45, respectively, and 0.1 ng/reaction of human genomic DNA (gDNA). Next, we implemented the assay on lateral flow strips, and the LOD was maintained for HPV16 and HPV18, but increased to 100 copies/reaction for HPV45 and to 1 ng/reaction for gDNA. Lastly, we used the LAMP test to evaluate total nucleic acid extracted from 38 clinical samples; compared to qPCR, the LAMP test had 89% sensitivity and 95% specificity. When integrated with sample preparation, this multiplexed LAMP assay could be useful for point-of-care testing.

RNA elements that controlhuman papillomavirus mRNA splicing-targets for therapy?

Human papillomaviruses (HPVs) cause more than 4.5% of all cancer in the world and more than half of these cases are attributed to human papillomavirus type 16 (HPV16). Prophylactic vaccines are available but antiviral drugs are not. Novel targets for therapy are urgently needed. Alternative RNA splicing is extensively used by HPVs to express all their genes and HPV16 is no exception. This process must function to perfection since mis-splicing could perturb the HPV gene expression program by altering mRNA levels or by generating dysfunctional mRNAs. Cis-acting RNA elements on the viral mRNAs and their cognate cellular trans-acting factors control papillomavirus RNA splicing. The precise but delicate nature of the splicing process renders splicing sensitive to interference. As such, papillomavirus RNA splicing is a potential target for therapy. Here we summarize our current understanding of cis-acting HPV16 RNA elements that control HPV16 mRNA splicing via cellular proteins and discuss how they may be exploited as targets for therapy to papillomavirus infections and cancer.

The role of endocervical curettage in the diagnosis of cervical intraepithelial neoplasia in human papillomavirus positive patients.

The role of endocervical curettage (ECC) in the diagnosis of cervical intraepithelial neoplasia (CIN) is a controversial topic. Investigate the role of ECC in the diagnosis of CIN in human papillomavirus (HPV) positive patients. Retrospective. A tertiary training and research hospital. This study included patients who were referred for colposcopy between 2018-2022 because of abnormal screening results. ECC results, age, cytology, HPV status, and colposcopic impression of the patients were extracted from the medical records. Multinomial logistic regression analyses were performed to identify factors that could predict CIN on ECC. The likelihood of high-grade squamous intraepithelial lesions (HSIL) in ECC in patients with cervical biopsy results of normal and low-grade squamous intraepithelial lesion (LSIL). 2895 women. In patients with normal and LSIL cervical biopsy results, HSILs were detected in 6.7% of ECC results. There was no difference in the detection rates of CIN in ECC among groups with smear results negative for intraepithelial lesions or malignancy (NILM), atypical squamous cells of undetermined significance (ASC-US), and LSIL. The likelihood of HSIL being observed in ECC was 2.2 times higher in patients with HPV16. The probability of LSIL disanois was 2.3 times higher in women aged 50-59 years and 2.8 times higher in women ≥ 60 years compared to the reference group of <30 years. The probability of LSIL was 2.3 and HSIL by ECC was 2.2 times higher in both age categories (P<.012 and P=.032, respectively) than the reference group of <30 years. Regardless of colposcopic findings, ECC should be performed in patients with smear results of NILM who are positive for HPV16, in patients with smear results of ASC-US and LSIL who are positive for any oncogenic type of HPV and in patients 50 and above with any result of smear or any oncogenic HPV type. We did not have the components of the HPV types in mixed groups.

Insights into the mechanisms and structure of breakage-fusion-bridge cycles in cervical cancer using long-read sequencing

Cervical cancer is caused by human papillomavirus (HPV) infection, has few approved targeted therapeutics, and is the most common cause of cancer death in low-resource countries. We characterized 19 cervical and four head and neck cancer cell lines using long-read DNA and RNA sequencing and identified the HPV types, HPV integration sites, chromosomal alterations, and cancer driver mutations. Structural variation analysis revealed telomeric deletions associated with DNA inversions resulting from breakage-fusion-bridge (BFB) cycles. BFB is a common mechanism of chromosomal alterations in cancer, and our study applies long-read sequencing to this important chromosomal rearrangement type. Analysis of the inversion sites revealed staggered ends consistent with exonuclease digestion of the DNA after breakage. Some BFB events are complex, involving inter- or intra-chromosomal insertions or rearrangements. None of the BFB breakpoints had telomere sequences added to resolve the dicentric chromosomes, and only one BFB breakpoint showed chromothripsis. Five cell lines have a chromosomal region 11q BFB event, with YAP1-BIRC3-BIRC2 amplification. Indeed, YAP1 amplification is associated with a 10-year-earlier age of diagnosis of cervical cancer and is three times more common in African American women. This suggests that individuals with cervical cancer and YAP1-BIRC3-BIRC2 amplification, especially those of African ancestry, might benefit from targeted therapy. In summary, we uncovered valuable insights into the mechanisms and consequences of BFB cycles in cervical cancer using long-read sequencing.

Cervicovaginal microbiota long-term dynamics and prediction of different outcomes in persistent human papillomavirus infection.

Persistent human papillomavirus (HPV) infection can lead to cervical intraepithelial neoplasia (CIN) and cervical cancer, posing serious threats to the health of women. Although the cervicovaginal microbiota is strongly associated with CIN, the dynamics of the microbiota during CIN development are unknown. In this retrospective cohort study, we analyzed 3-year longitudinal data from 72 patients diagnosed with a persistent HPV infection almost all caused by high-risk HPV types. Patients were categorized into groups with HPV persistent infection (n = 37), progression to CIN (n = 16), and CIN regression (n = 19) based on infection outcome during the follow-up period. Furthermore, 16S rRNA gene sequencing was performed on consecutively collected cervical samples to explore the composition and dynamics of the cervicovaginal microbiota during the development and regression of CIN. Our results showed that the composition of the cervicovaginal microbiota varied among women with different HPV infection outcomes and remained relatively stable during the follow-up period. Notably, the serial follow-up data showed that these microbial alterations were present for at least 1-2 years and occurred before pathologic changes. In addition, microbial markers that were highly discriminatory for CIN progression or regression were identified. This study provides evidence for a temporal relationship between changes in the cervicovaginal microbiota and the development of CIN, and our findings provide support for future microbial intervention strategies for CIN.

Advanced technologies towards improved HPV diagnostics.

Persistent infection with high-risk types of human papillomaviruses (HPV) is a major cause of cervical cancer, and an important factor in other malignancies, for example,head and neck cancer. Despite recent progress in screening and vaccination, the incidence and mortality are still relatively high, especially in low-income countries. The mortality and financial burden associated with the treatment could be decreased if a simple, rapid, and inexpensive technology for HPV testing becomes available, targeting individuals for further monitoring with increased risk of developing cancer. Commercial HPV tests available in the market are often relatively expensive, time-consuming, and require sophisticated instrumentation, which limits their more widespread utilization. To address these challenges, novel technologies are being implemented also for HPV diagnostics that include for example, isothermal amplification techniques, lateral flow assays, CRISPR-Cas-based systems, as well as microfluidics, paperfluidics and lab-on-a-chip devices, ideal for point-of-care testing in decentralized settings. In this review, we first evaluate current commercial HPV tests, followed by a description of advanced technologies, explanation of their principles, critical evaluation of their strengths and weaknesses, and suggestions for their possible implementation into medical diagnostics.

Strengthening the relationship between intractable plantar keratosis and human papillomavirus.

The aim of the study was to determine the presence of human papillomavirus (HPV) in patients with intractable plantar keratosis (IPK) by comparing the histopathological findings of biopsies. A prospective, observational, and concordance study was carried out. Three different specimens were taken from each IPK. A first punch was sent for histopathological examination, and a second punch and a superficial skin scraping were both sent for HPVpolymerase chain reaction (PCR)and type determination. A total of 51 patients were included. From the histopathological examination, it was determined that 35 (68.6%) samples were diagnosed as warts and 16 (31.3%) as keratosis. However, the presence of HPV was confirmed by PCR in 49 (96.1%) and in 42 (82.4%) samples obtained by punch and superficial scraping, respectively. In the 49 PCR-positive samples, the most common HPV types were HPV1, HPV2, HPV27, HPV57, and HPV65, accounting for 81.6% of the samples.In conclusion, this study demonstrates that HPV infection and IPK lesions are very closely related. Although we cannot confirm that HPV is the cause of the development of IPK, the high prevalence of HPV observed in these lesions calls for a change to the procedures for managing IPK.

Comparison of four different human papillomavirus genotyping methods in cervical samples: Addressing method-specific advantages and limitations

Since human papillomavirus (HPV) is recognized as the causative agent of cervical cancer and associated with anogenital non-cervical and oropharyngeal cancers, the characterization of the HPV types circulating in different geographic regions is an important tool in screening and prevention. In this context, this study compared four methodologies for HPV detection and genotyping: real-time PCR (Cobas® HPV test), nested PCR followed by conventional Sanger sequencing, reverse hybridization (High + Low PapillomaStrip® kit) and next-generation sequencing (NGS) at an Illumina HiSeq2500 platform. Cervical samples from patients followed at the Family Health Strategy from Juiz de Fora, Minas Gerais, Brazil, were collected and subjected to the real-time PCR. Of those, 114 were included in this study according to the results obtained with the real-time PCR, considered herein as the gold standard method. For the 110 samples tested by at least one methodology in addition to real-time PCR, NGS showed the lowest concordance rates of HPV and high-risk HPV identification compared to the other three methods (67–75 %). Real-time PCR and Sanger sequencing showed the highest rates of concordance (97–100 %). All methods differed in their sensitivity and specificity. HPV genotyping contributes to individual risk stratification, therapeutic decisions, epidemiological studies and vaccine development, supporting approaches in prevention, healthcare and management of HPV infection.

Immunogenicity of 2-Dose HPV Vaccine Series for Postpartum Women

Postpartum human papillomavirus (HPV) vaccination is a promising strategy to increase HPV vaccination uptake in the US, particularly for reaching vaccine-naive women and those who lack health insurance beyond the pregnancy period. However, completion of the 3-dose vaccine regimen is challenging. To evaluate the immunogenicity of a 2-dose postpartum HPV vaccination regimen (0 and 6 months) and assess whether it is noninferior to a 3-dose postpartum HPV vaccination regimen (0, 1-2, and 6 months) administered to historical controls. A noninferiority, open-label, nonrandomized immunogenicity trial was conducted from August 4, 2020, to June 23, 2022, of postpartum patients aged 15 to 45 years who delivered at 2 hospitals in Baltimore, Maryland. Historical controls were adolescents and young women aged 16 to 26 years. Two doses of the nonavalent HPV vaccine administered 6 months apart. The primary outcome was noninferiority (90% CI, lower bound >0.67) of the geometric mean titer (GMT) ratio for HPV-16 among postpartum women compared with historical controls. Secondary outcomes were noninferiority of GMT ratios for the other 8 HPV types and percentage seroconversion for each HPV type. As a noninferiority trial, the primary analysis used the per-protocol analysis. Of 225 enrolled participants, the mean (SD) age at baseline was 29.9 (6.8) years, and 171 (76.0%) were HPV-16 seronegative at baseline. Of these 171 participants, 129 (75.4%) received a second vaccine dose and completed the subsequent 4-week serologic measurements. Relative to historical controls, the HPV-16 GMT ratio was 2.29 (90% CI, 2.03-2.58). At month 7, HPV-16 GMT was higher after the 2-dose regimen (7213.1 mMU/mL [90% CI, 6245.0-8331.4 mMU/mL]) than among historic controls after the 3-dose regimen (3154.0 mMU/mL [90% CI, 2860.2-3478.0 mMU/mL]). Similarly, the lower bound of the 90% CI of the GMT ratio was above 1 for the 8 HPV types 6, 11, 18, 31, 33, 45, 52, and 58. A total of 118 of 134 women (88.1%) seroconverted for HPV-16 after the first dose; 4 weeks after the second dose, the seroconversion rate was 99% or greater for all HPV types. This study suggests that immunogenicity of a 2-dose HPV vaccination regimen given 6 months apart among postpartum women was noninferior to a 3-dose regimen among young historical controls. Most women seroconverted after the first dose of the 2-dose regimen. These results demonstrate that postpartum vaccination using a reduced schedule may be a promising strategy to increase HPV vaccine series completion. ClinicalTrials.gov Identifier: NCT04274153.

Immune response following a two-dose schedule of bivalent HPV vaccination among girls and boys.

This longitudinal cohort study describes the kinetics in antibody levels after two doses of the bivalent human papillomavirus (HPV) vaccine in girls (birth cohort 2001) vaccinated in the routine Dutch vaccination program at 12 years of age, up to 7.5 years post-vaccination. Also, the antibody response one month post-vaccination of the first cohort of boys (birth cohort 2012, vaccinated at 10 years of age) eligible for HPV vaccination in the Netherlands is presented. Blood samples and questionnaire data were collected of girls and boys. HPV type-specific antibody concentrations (LU/mL) against HPV16/18/31/33/45/52/58 were assessed using a validated virus-like particle (VLP) multiplex immunoassay. For girls, antibody decays over time were modelled using the modified power-law decay model and the exponential decay model. The Geometric Mean Concentrations (GMCs) remained higher for HPV16/18 than for HPV types 31, 33, 45, 52, and 58 among girls up to 7.5 years post-vaccination. The antibody levels of HPV16 and HPV18 reached plateau values of 482 and 159 LU/mL, respectively. Mathematical modelling showed that the half-life values of HPV16/18 were 2.4- to 4.5-fold higher compared with the half-life values of the other HPV types. Among boys (aged 10 years), the GMC for HPV16 was significantly higher than among girls one month post-vaccination (aged 12 years). The GMCs of all HPV types declined over time, although the GMCs of HPV16/18 remained relatively high up to 7.5 years post-vaccination. The GMCs for HPV16/18 among boys were at least equally high as the GMCs among girls at one month post-vaccination. Further follow-up of the cohort of boys is needed to gain knowledge on long-term immune responses of young boys following bivalent HPV vaccination.

Vaccine and Non-Vaccine HPV Types Presence in Adolescents with Vertically Acquired HIV Five Years Post Gardasil Quadrivalent Vaccination: The ZIMGARD Cohort.

Human papillomavirus (HPV) vaccination programs are a key intervention in protecting individuals against HPV-related disease. HIV1-infected individuals are at increased risk of HPV-associated cancers. This study was conducted to evaluate the potential role of prophylactic HPV vaccines in preventing new HPV infections among participants with perinatally acquired HIV who received the quadrivalent HPV vaccine at least five years before this study. This cross-sectional study was conducted at Newlands Clinic, Harare, Zimbabwe. The clinic provided the Gardasil quadrivalent HPV vaccine (4vHPV) to 624 adolescents living with HIV starting in December 2015. Vaginal and penile swabs were collected and tested for HPV types from the study participants who had received the 4vHPV vaccine 5-6 years before enrolment. We present the results of 98 participants (44.6% female) vaccinated at a median age of 15 years (IQR 12-16). The mean amount of time since vaccination was 6 years (SD: ±0.4). The HPV-positive rate amongst the analyzed swabs was 69% (68/98). Among 30/98 (31%) HPV-positive participants, 13/98 (13%) had low-risk HPV types, and 17/98 (17%) had high-risk HPV types. Twelve participants tested positive for HPV18, only one participant tested positive for HPV16, and an additional four (4.3%) tested positive for either type 6 or 11, with respect to vaccine-preventable low-risk HPV types. The Gardasil quadrivalent HPV vaccine (4vHPV) was expected to protect against infection with HPV types 16, 18, 6, and 11. We demonstrated a possible waning of immunity to HPV18 in 17% of the participants, and an associated loss in cross-protection against HPV45. We observed a relatively high prevalence of 'opportunistic non-vaccine HPV types' or 'ecological niche occupiers' in this cohort, and suggest further research on the involvement of these types in cervical and other genital cancers. Our study is one of the few, if not the first, to report on HPV vaccine immunoprotection among people living with HIV (PLWH), thereby setting a baseline for further studies on HPV vaccine effectiveness among PLWH.

Prevalence of high-risk human papillomavirus infection and genotype distribution among Kazakhstani women with abnormal cervical cytology

Aim This study aimed to identify the prevalence and distribution of high-risk human papillomavirus (HR-HPV) types among Kazakhstani women with abnormal cervical cytology. Methods A cross-sectional study was performed from May 2019 to June 2020. Cervical samples were collected from women in the different regions of Kazakhstan. Results A total of 316 patients’ samples were analysed for HR-HPV using real-time multiplex PCR. Cervical cytology abnormalities were reported according to the Bethesda classification. HPV detection by cytology showed a statistically significant association with HPV status and the number of HPV infection types (p < .05). Among women with abnormal cervical cytology, 62.4% were positive for HPV infection of those 79.4% had low-grade squamous intraepithelial lesions (LSIL), and 20.6% had high-grade squamous intraepithelial lesions (HSIL). Among patients with LSIL, 77.4% had HPV16 and 58.8% were infected with HPV18. Among patients with HSIL, 41.2% had HPV18 and 22.6% – HPV16. Conclusions There is a high prevalence of HR-HPV types among Kazakhstani women with abnormal cervical cytology. The most identified types were HPV16, 18, 31, 33 and 52. There is an emergency need to implement an HPV vaccination program to prevent cervical lesion development.