From the monovalent to the nine-valent HPV vaccine

Genetic diversity, variation and recombination among the human papillomaviruses (HPVs) genomes isolated in China: a comparative genomic and phylogenetic analysis

Human papillomaviruses (HPVs) are widespread, sexually transmitted group of viruses that infect most individuals at some stage, causing genital warts and cancers. They are members of the Papillomaviridae family, which contains about 400 HPV types. China is among the high HPV burden countries with reported infections of multiple HPV types, accounting for 17.3% of global deaths and 18.2% of global new cases. Thus, understanding the genetic variation and geographic diversity characteristics of HPVs isolated in China is critical for global HPV prevention strategies. Thus, we analyzed the available HPV genome sequences isolated in China that grouped into two categories (alpha- and gamma-papillomaviruses) based on full-length genomes. The most common were HPV-16, -6, -58, and -52 respectively. In addition, four of the novel strains isolated in China, e.g. TG550, JDFY01, CH2, and L55 clustered with the HPV-mSK 159, 244, 201, and 200 respectively. Our phylogeographic network analysis indicated that the L55, TG550, and CH2 are genetically identical to the mSK 200, 046, and 201 respectively, while JDFY01 appeared separately, connected to the mSK-040 following five mutational steps. Also, we found ten recombination events among HPV-6/11 types within their E1, E2, E7, L1/L2 proteins, and Long Control Region ORFs. We achieved the consensus amino acid sequences of HPV proteins and found a conserved stretch of amino acids within E5A of all HPVs circulating in China. These findings offer valued insights into the genetic relationships, distribution, and evolution of the HPVs in China that may assist in adapting effective HPV preventive measures.

The potential use of therapeutics and prophylactic mRNA vaccines in human papillomavirus (HPV)

Cervical cancer (CC) and other malignant malignancies are acknowledged to be primarily caused by persistent human papillomavirus (HPV) infection. Historically, vaccinations against viruses that produce neutralizing antibodies unique to the virus have been an affordable way to manage viral diseases. CC risk is decreased, but not eliminated, by HPV vaccinations. Since vaccinations have been made available globally, almost 90% of HPV infections have been successfully avoided. On the lesions and diseases that are already present, however, no discernible treatment benefit has been shown. As a result, therapeutic vaccines that elicit immune responses mediated by cells are necessary for the treatment of established infections and cancers. mRNA vaccines possess remarkable potential in combating viral diseases and malignancy as a result of their superior industrial production, safety, and efficacy. Furthermore, considering the expeditiousness of production, the mRNA vaccine exhibits promise as a therapeutic approach targeting HPV. Given that the HPV-encoded early proteins, including oncoproteins E6 and E7, are consistently present in HPV-related cancers and pre-cancerous lesions and have crucial functions in the progression and persistence of HPV-related diseases, they serve as ideal targets for therapeutic HPV vaccines. The action mechanism of HPV and HPV-related cancer mRNA vaccines, their recent advancements in clinical trials, and the potential for their therapeutic applications are highlighted in this study, which also offers a quick summary of the present state of mRNA vaccines. Lastly, we highlight a few difficulties with mRNA HPV vaccination clinical practice and provide our thoughts on further advancements in this quickly changing sector. It is expected that mRNA vaccines will soon be produced quickly for clinical HPV prevention and treatment.

Screening for High-Risk Human Papillomavirus Reveals HPV52 and HPV58 among Pediatric and Adult Patient Saliva Samples

Previous research has demonstrated that the human papillomavirus (HPV) can infect a wide range of human tissues, including those within the oral cavity. High-risk oral HPV strains have been associated with the development and progression of oral cancers, including oral squamous cell carcinomas. Although many studies have examined the prevalence of the high-risk strains HPV16 and HPV18, far fewer have assessed the prevalence of other high-risk HPV strains. An approved study protocol was used to identify HPV52 and HPV58 among clinical samples (n = 87) from a saliva biorepository. Quantitative polymerase chain reaction (qPCR) and validated primers for HPV52 and HPV58 were used to facilitate this screening. This screening demonstrated that a total of n = 4/45 or 8.9% of adult saliva samples harbored high-risk HPV52, and n = 2/45 or 4.4% tested positive for high-risk HPV58. In addition, a total of n = 6/42 or 14.3% of the pediatric saliva samples tested positive for high-risk HPV, including n = 5/42 or 11.9% with HPV52 and n = 3/42 or 7.1% for HPV58. These data demonstrate the presence of the high-risk oncogenic HPV52 and HPV58 strains among both adult and pediatric clinical patient samples. More detailed longitudinal research must be conducted to determine whether this prevalence may be increasing or decreasing over time. In addition, these data strongly support public health prevention efforts, such as knowledge and awareness of the nine-valent HPV vaccine covering additional high-risk strains, including HPV52 and HPV58.

A survey of potential acceptance of 9-valent HPV vaccine among Chinese male college students

Human papillomavirus (HPV) has a great impact on world health. Vaccination is among the most important methods of preventing HPV infection. This study investigated Chinese male college students' knowledge of, attitude toward, and acceptance of the 9vHPV vaccine and the independent predictors. An online cross-sectional study was conducted among male college students at Chinese colleges and universities from March 12 to March 23, 2022. Based on a literature review of similar studies, a self-questionnaire was designed to investigate the students' knowledge of, attitude toward, and acceptance of the 9vHPV vaccine. Multivariate logistic regression analysis was performed to identify factors influencing their willingness to be vaccinated. In addition, the structural equation model was constructed. A total of 1,547 male college students completed the survey. Of all the students, 54.95% were unwilling to receive a 9vHPV vaccination, while only 45.05% expressed willingness. Multivariate logistic regression analysis revealed that the male college students willing to receive the vaccine included medical students, those in a romantic relationship, those whose relatives and friends had cervical cancer, those whose relatives and friends had received the 9vHPV vaccine, those supportive of promoting the vaccine for men, and those who would recommend the vaccine to their relatives and friends. Male college students exhibited high hesitancy toward the 9vHPV vaccine. Acceptance of the 9vHPV vaccine by male college students can be improved by deepening their accurate understanding of the vaccine and enhancing their positive attitude toward it.

Updates on HPV Vaccination

Cervical cancer still poses a significant global challenge. Developed countries have mitigated this challenge by the introduction of structured screening programmes and, more recently, the HPV vaccine. Countries that have successfully introduced national HPV vaccination programmes are on course for cervical cancer elimination in a few decades. In developing countries that lack structured screening and HPV vaccination programmes, cervical cancer remains a major cause of morbidity and mortality. The HPV vaccine is key to addressing the disproportionate distribution of cervical cancer incidence, with much to be gained from increasing vaccine coverage and uptake globally. This review covers the history and science of the HPV vaccine, its efficacy, effectiveness and safety, and some of the considerations and challenges posed to the achievement of global HPV vaccination coverage and the consequent elimination of cervical cancer.

Prognostic significance of HPV16 infection in oral squamous cell carcinoma

Background/Aim: Many studies confirmed strong association between oncogenic genotypes of Human Papillomaviruses (HPVs) and some oropharyngeal and oral squamous cell carcinomas (OSCCs). The aim of this study was to determine the prognostic significance of HPV16 infection in OSCC in population of Montenegro i.e. correlation between HPV16 infection and disease free interval (DFI), disease recurrence and metastasis occurrence. Material and Methods: We examined surgically obtained specimens from 60 patients with OSCC (localized on the lower lip, tongue or/and floor of the mouth) in six years period. Tumor tissue samples were used for histological analysis and HPV16 genome PCR detection (primers for detection of E6 gene). Patients were followed up for the 3 years. Results: HPV16 infection was more commonly detected in females with OSCC (p=0.038), while no correlation between this infection and disease recurrence (p= 0.122) and/or metastasis occurrence (p= 0.934) was found. DFI was not significantly different between patients with or without HPV16 infection (p= 0.427), but DFI was significantly shorter (p= 0.003) in females with oral HPV16 infection compared to male patients with this infection. Conclusions: Counting that HPV16 infection has a negative prognostic significance in OSCC, the HPV immunization program against genital HPV infection, would also have a positive impact on the frequency of HPV-mediated OSCC in Montenegrin population.

Public health impact and cost-effectiveness of switching from bivalent to nonavalent vaccine for human papillomavirus in Norway: incorporating the full health impact of all HPV-related diseases

AIM

The objective of this study was to estimate and compare the cost-effectiveness of switching from a bivalent to a nonavalent human papillomavirus (HPV) vaccination program in Norway, incorporating all nonavalent vaccine-preventable HPV-related diseases and in the context of the latest cervical cancer screening program.

METHODS

A well-established dynamic transmission model of the natural history of HPV infection and disease was adapted to the Norwegian population. We determined the number of cases of HPV-related diseases and subsequent number of deaths, and the economic burden of HPV-related disease under the current standard of care conditions of bivalent and nonavalent vaccinations of girls and boys aged 12 years.

RESULTS

Compared to bivalent vaccination, nonavalent vaccination averted an additional 4,357 cases of HPV-related cancers, 421,925 cases of genital warts, and 543 cases of recurrent respiratory papillomatosis (RRP) over a 100-year time horizon. Nonavalent vaccination also averted an additional 1,044 deaths over the 100-year time horizon when compared with bivalent vaccination. Total costs were higher for the nonavalent strategy (10.5 billion NOK [€1.03 billion] vs. 9.3-9.4 billion NOK [€915-925 million] for bivalent vaccination). A switch to nonavalent vaccination had a higher vaccination cost (4.4 billion NOK [€433 million] vs. 2.7 billion NOK [€266 million] for bivalent vaccination) but resulted in a savings of 627-694 million NOK [€62-68 million] in treatment costs. A switch to nonavalent vaccination demonstrated an incremental cost-effectiveness ratio of 102,500 NOK (€10,086) per QALY versus bivalent vaccination.

CONCLUSIONS

Using a model that incorporated the full range of HPV-related diseases, and the latest cervical cancer screening practices, we found that switching from bivalent to nonavalent vaccination would be considered cost-effective in Norway.

Cross-variant protection against SARS-CoV-2 infection in hamsters immunized with monovalent and bivalent inactivated vaccines

Rapid development and successful use of vaccines against SARS-CoV-2 might hold the key to curb the ongoing pandemic of COVID-19. Emergence of vaccine-evasive SARS-CoV-2 variants of concern (VOCs) has posed a new challenge to vaccine design and development. One urgent need is to determine what types of variant-specific and bivalent vaccines should be developed. Here, we compared homotypic and heterotypic protection against SARS-CoV-2 infection of hamsters with monovalent and bivalent whole-virion inactivated vaccines derived from representative VOCs. In addition to the ancestral SARS-CoV-2 Wuhan strain, Delta (B.1.617.2; δ) and Theta (P.3; θ) variants were used in vaccine preparation. Additional VOCs including Omicron (B.1.1.529) and Alpha (B.1.1.7) variants were employed in the challenge experiment. Consistent with previous findings, Omicron variant exhibited the highest degree of immune evasion, rendering all different forms of inactivated vaccines substantially less efficacious. Notably, monovalent and bivalent Delta variant-specific inactivated vaccines provided optimal protection against challenge with Delta variant. Yet, some cross-variant protection against Omicron and Alpha variants was seen with all monovalent and bivalent inactivated vaccines tested. Taken together, our findings support the notion that an optimal next-generation inactivated vaccine against SARS-CoV-2 should contain the predominant VOC in circulation. Further investigations are underway to test whether a bivalent vaccine for Delta and Omicron variants can serve this purpose.

Prevalence and clinical implications of the HPV16 infection in oral cancer in Montenegro – Evidence to support the immunization program

Oral squamous cell carcinoma (OSCC) makes 85–95% of all malignances in the oral cavity. Increasing evidence shows that the Human Papillomaviruses (HPVs) are preferentially associated with some oropharyngeal and OSCCs, namely the genotype 16. The aim of the present study was to determine the prevalence and clinical implications of HPV16 infection in oral squamous cell carcinoma in population of Montenegro.

This study included 60 patients with OSCC (localized on the lower lip, tongue or/and floor of the mouth), surgically treated at the Clinical Centre of Montenegro from 2012 to 2018. Surgically obtained formalin-fixed and paraffin-embedded specimens were used for histopathological analysis and HPV16 genome detection using standard Polymerase Chain Reaction (primers for detection of E6 gene). Each individual was further followed up for the period of three years and for different clinico-pathological characteristics, including disease free interval (DFI).

The prevalence of HPV16 infection in OSCCs was 23.3% and the infection was significantly more common in female patients (P = 0.038). No significant correlation was detectable between HPV16 infection and the patients' age (P = 0.302), tumor site (P = 0.125), tumor grade (P = 0.363) and disease stage (P = 0.995). Observing the total sample the DFI was not significantly different for HPV16-positive versus HPV16-negative patients (P = 0.427), but a gender-based difference in DFI was observed, with the significantly shorter DFI (Log Rank test, P = 0.003) in HPV16 positive female patients compared to male patients (P = 0.003).

The results obtained in this study provide scientific evidence for the development of national HPV vaccination program in Montenegro.

HPV Vaccination after Primary Treatment of HPV-Related Disease across Different Organ Sites: A Multidisciplinary Comprehensive Review and Meta-Analysis

Objective: To assess evidence on the efficacy of adjuvant human papillomavirus (HPV) vaccination in patients treated for HPV-related disease across different susceptible organ sites. Methods: A systematic review was conducted to identify studies addressing the efficacy of adjuvant HPV vaccination on reducing the risk of recurrence of HPV-related preinvasive diseases. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI). Results: Sixteen studies were identified for the final analysis. Overall, 21,472 patients with cervical dysplasia were included: 4132 (19.2%) received the peri-operative HPV vaccine, while 17,340 (80.8%) underwent surgical treatment alone. The recurrences of CIN 1+ (OR 0.45, 95% CI 0.27 to 0.73; p = 0.001), CIN 2+ (OR 0.33, 95% CI 0.20 to 0.52; p < 0.0001), and CIN 3 (OR 0.28, 95% CI 0.13 to 0.59; p = 0.0009) were lower in the vaccinated than in unvaccinated group. Similarly, adjuvant vaccination reduced the risk of developing anal intraepithelial neoplasia (p = 0.005) and recurrent respiratory papillomatosis (p = 0.004). No differences in anogenital warts and vulvar intraepithelial neoplasia recurrence rate were observed comparing vaccinated and unvaccinated individuals. Conclusions: Adjuvant HPV vaccination is associated with a reduced risk of CIN recurrence, although there are limited data regarding its role in other HPV-related diseases. Further research is warranted to shed more light on the role of HPV vaccination as adjuvant therapy after primary treatment.

Distribution of vaccine-related high-risk human papillomaviruses and their impact on the development of cervical dysplasia in women in Montenegro

Cervical cancer (CC) is the third leading cause of death in women in Montenegro. Human papillomavirus (HPV) is the causative agent of CC however, HPV genotype distribution varies across regions. This study examined the distribution and impact of vaccine-related high-risk (HR)-HPVs on the development of cervical dysplasia in Montenegrin women. A total of 187 women who had a clinical indication for cervical biopsy were enrolled. Based on histopathological findings, women were classified into 2 groups, with and without dysplasia. HR-HPV was detected by real-time PCR. Twelve HR-HPV genotypes were detected in 40.6% of cervical samples. The 7 most prevalent HR-HPVs in order of decreasing frequency were HPV 16 (39.5%), 45 (23.7%), 31 (21.0%), 33 (17.1%), 18 (6.6%), 52 (6.6%), and 58 (6.6%), all of them are targeted by nonavalent vaccine. Vaccine-related HR-HPVs had a higher prevalence (92.1%) than the other HR-HPVs detected in HR-HPV-positive samples. Among HR-HPV-positive women, HPV 16 and 33 were more common in women with dysplasia than in those without dysplasia (HPV 16: 28.9 vs 7.2%; HPV 33: 11.8 vs 3.6%). HPV 16 was the most common HR-HPV genotype in cervical samples, followed by HPV 45, 31, 33, 18, 52, and 58. HPV 16 and 33 were shown to be associated with the development of cervical dysplasia. These results indicate that prophylactic nonavalent vaccine can potentially prevent approximately 90% of HR-HPV infections and 60% of cervical dysplasia cases in Montenegrin women.

Peter L, Studentsov Y, Nucci-Sack A, Diaz A, Pickering S, Schlecht NF, Burk RD. Anti-HPV16 Antibody Titers Prior to an Incident Cervical HPV16/31 Infection

The goal of this study was to investigate the serological titers of circulating antibodies against human papillomavirus (HPV) type 16 (anti-HPV16) prior to the detection of an incident HPV16 or HPV31 infection amongst vaccinated participants. Patients were selected from a prospective post-HPV vaccine longitudinal cohort at Mount Sinai Adolescent Health Center in Manhattan, NY. We performed a nested case-control study of 43 cases with incident detection of cervical HPV16 (n = 26) or HPV31 (n = 17) DNA who had completed the full set of immunizations of the quadrivalent HPV vaccine (4vHPV). Two control individuals whom had received three doses of the vaccine (HPV16/31-negative) were selected per case, matched on age at the first dose of vaccination and follow-up time in the study: a random control, and a high-risk control that was in the upper quartile of a sexual risk behavior score. We conducted an enzyme-linked immunosorbent assay (ELISA) for the detection of immunoglobulin G (IgG) antibodies specific to anti-HPV16 virus-like particles (VLPs). The results suggest that the average log antibody titers were higher among high-risk controls than the HPV16/31 incident cases and the randomly selected controls. We show a prospective association between anti-HPV16 VLP titers and the acquisition of an HPV16/31 incident infection post-receiving three doses of 4vHPV vaccine.

Prevalence and type distribution of human papillomavirus infections in Danish patients diagnosed with vulvar squamous cell tumors and precursors

OBJECTIVE

To study the prevalence and type distribution of human papillomavirus (HPV) in patients with vulvar high-grade precancerous lesions and vulvar squamous cell carcinoma (VSCC).

METHODS

Formalin-fixed and paraffin-embedded (FFPE) tissue samples from Danish patients diagnosed with vulvar precancerous lesions or VSCC in the period from 2010 to 2012 were obtained. HPV-DNA detection was carried out by the use of polymerase chain reaction (PCR) using GP5+/GP6+ primers and genotyped by sequencing. A systematic literature search on the PubMed database was performed to investigate the prevalence and genotype distribution worldwide.

RESULTS

In the present study population (n = 149) 52 vulvar high-grade squamous intraepithelial lesions (HSIL), 2 differentiated vulvar intraepithelial neoplasia (dVIN), and 95 VSCC cases were identified. HPV was detected in 85 patients (57.0%). Overall, a higher proportion of the vulvar high-grade precancerous lesions were HPV positive compared to VSCC (83.6% vs. 42.1%, p < 0.001). Additionally, HSIL had a significantly higher HPV-positive rate compared to keratinizing VSCC (84.6% vs. 33.3%, p < 0.001). However, the HPV positivity was comparable between HSIL and non-keratinizing VSCC (84.6% vs. 82.4%, p = 0.825). One dVIN was HPV positive whereas the other was HPV negative. HPV-16 was the most common HPV type (68.2%), followed by HPV-33 (18.8%) and HPV-18 (8.2%).

CONCLUSIONS

Most vulvar HSIL and non-keratinizing VSCCs appear to be HPV associated. However, we find a high HPV association in keratinizing VSCC, which needs to be further studied. HPV-16 remains the predominant genotype, but HPV-33 also seems to play a role in the development of VSCC.

Adjuvant HPV Vaccination to Prevent Recurrent Cervical Dysplasia after Surgical Treatment: A Meta-Analysis

Objective: The aim of this meta-analysis was to discuss evidence supporting the efficacy of adjuvant human papillomavirus (HPV) vaccination in reducing the risk of recurrent cervical intraepithelial neoplasia (CIN) 2 or greater after surgical treatment. Methods: A systematic literature search was performed for studies reporting the impact of HPV vaccination on reducing the risk of recurrence of CIN 2+ after surgical excision. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI). Results: Eleven studies met the inclusion criteria and were selected for analysis. In total, 21,310 patients were included: 4039 (19%) received peri-operational adjuvant HPV vaccination while 17,271 (81%) received surgery alone. The recurrence of CIN 2+ after treatment was significantly lower in the vaccinated compared with the unvaccinated group (OR 0.35; 95% CI 0.21–0.56; p < 0.0001). The recurrence of CIN 1+ after treatment was significantly lower in the vaccinated compared with the unvaccinated group (OR 0.51; 95% CI 0.31–0.83; p = 0.006). A non-significant trend of reduction rate of HPV persistence was observed in the vaccinated compared with the unvaccinated cohorts (OR was 0.84; 95% CI 0.61–1.15; p = 0.28). Conclusions: HPV vaccination, in adjuvant setting, is associated with a reduced risk of recurrent CIN 1+ and CIN 2+ after surgical treatment.

Postvaccination prevalence of vaccine-Human Papillomavirus (vHPV) genotypes among the target population: A systematic review and meta-analysis

Human Papillomavirus (HPV) vaccines are safe and are highly effective in reducing the prevalence of HPV infections and subsequent HPV associated diseases in the target population. A systematic review and meta-analysis was carried out searching electronic databases for articles published between January 2007 and September 2020 reporting the prevalence estimates of vaccine HPV (vHPV) types in women who had received one or more doses of quadrivalent or bivalent vaccines. This systematic review was based on standard systematic review guidelines and the meta-analysis was performed by pooling the HPV vaccine type prevalence data with 95% confidence interval (CI) among 16,929 young women who had received the prophylactic HPV vaccines before the age of 27 years. The overall pooled prevalence of vHPV types was.0.04 (95% CI: 0.02, 0.05). The meta-analysis concludes that prophylactic HPV vaccination before the age of 27 years results in a decline of vHPV types in young women.

Sex difference in the immunogenicity of the quadrivalent Human Papilloma Virus vaccine: Systematic review and meta-analysis

BACKGROUND

Immunological differences between males and females in response to viral vaccines are well known. This the first review to examine them for the Human Papilloma Virus.

METHODS

We conducted a systematic review and meta-analysis of the immunogenicity of the Quadrivalent Human Papilloma Virus Vaccine qHPVV. We searched Medline, Embase, and CENTRAL for trials published until September 17, 2019. Inclusion criteria were 3-doses and reporting geometric mean titers (GMTs). We performed random-effects meta-analyses and meta-regression separated by age group and sex.

RESULTS

Our search yielded 1809 unique studies. 334 full texts were screened and data from 18 studies were extracted. Females had higher pooled geometric mean titers than males in all age groups. Log transformed GMTs in male children (<16) years were: against HPV6: 6·62 (95% CI 6·29-6·94; I² = 86·0%), against HPV11: 7·07 (95% CI 6·90-7·23; I² = 63.1%), against HPV16: 8·53 (95% CI 8·28-8·78; I² = 73·0%), and against HPV18 7·21 (95% CI 7·08-7·34; I² = 26·4%). In females: against HPV6 7·10 (95% CI 6·79-7·41; I² = 96·6%), HPV11: 7·32 (95% CI 7·15-7·50; I² = 90·6%), HPV16: 8·71 (95% CI 8·52-8·91; I² = 90·2%), and HPV18 7·35 (95% CI 7·11-7·58; I² = 92·7%). In the meta-regression, the sexual difference was significant for HPV6 (p = 0·022) with a similar tendency for HPV11 (p = 0·066) and HPV18 (p = 0·079). Immunogenicity was significantly higher in children (<16) than in adults (p < 0·001).

CONCLUSION

Females have higher antibody titers against HPV after receiving the qHPVV than do males. The difference is bigger in low-risk HPV strains. Adjusting the doses and schedules for each sex should be explored further.

Recent developments in immunotherapy of cancers caused by human papillomaviruses

A subset of oncogenic human papillomaviruses (HPVs) is the main cause of genital cancers, most importantly cervical cancer and an increasing number of head and neck cancers. Despite the availability of prophylactic vaccines against the most prevalent oncogenic HPV types, HPV‐induced malignancies are still a major health and economic burden. Besides conventional treatment with surgery, chemotherapy and radiation, immunotherapy is emerging as an efficient adjuvant option. Here, we review relevant studies and ongoing clinical trials using immune checkpoint inhibitors, therapeutic vaccines, gene editing approaches and adoptive T cell therapies, with special focus on engineered TCR T cells, which are showing encouraging results and could lead to significant improvement in the treatment of HPV+‐infected cancer patients.

The oncogenic pathways of papillomaviruses

Papillomaviruses are oncogenic DNA viruses and induce hyperplastic benign lesions of both cutaneous and mucosal tissues in their various hosts, including many domestic and wild animals as well as humans. There are some Papillomavirus genotypes that can infect hosts different from their own, such as BPV 1 and BPV 2 originated from cattle, which can also infect horses and are responsible for fibroblastic tumours in horses. This review article summarizes the origin and evolution of papillomaviruses as an etiological agent in the historical process. The main focus in this review is the evaluation of the interactions between high-risk papillomavirus oncoproteins and programmed cell-death pathways. It further exemplifies the role of these interactions in the malignant cell transformation process. In parallel with this, the use and importance of the bovine model system to enlighten the papillomavirus-associated cancers is discussed with an in-depth examination. Furthermore, it focuses on the epidemiological situation of BPV infections in Turkey in the cattle herds.

Prevalence and genotype distribution of genital human papillomavirus infection in female sex workers in the world: a systematic review and meta-analysis

BACKGROUND

Female sex workers (FSWs) are amongst the most susceptible groups to acquire human papillomavirus (HPV) infection and consequently, to develop cervical intraepithelial neoplasia and cervical cancer. This is the first systematic review and meta-analysis to provide estimates of the pooled prevalence of HPV infection and the distribution of HPV types among FSWs across the world.

METHODS

Five computerized databases were searched for relevant studies published since the inception date of databases to September 2019. The pooled HPV prevalence was calculated by the random effect model described by DerSimonian-Laird. Subgroup analysis was performed to identify the probable sources of heterogeneity. The meta-analysis was performed using the "Metaprop" function in the R package Meta.

RESULTS

Sixty-two studies involving 21,402 FSWs from 33 countries were included in this meta-analysis, and the pooled HPV prevalence was 42.6% (95% confidence interval (CI): 38.5-46.7%). HPV-16 (10.1, 95% CI: 8.2-12.5%), HPV-52 (7.9, 95% CI: 5.9-10.7%), and HPV-53 (6.0, 95% CI: 4.4-8.1%) were the most common high-risk HPV types identified among FSWs. The pooled estimated prevalence of HPV infection among FSWs before and after 2010 were slightly different, 43.6% (95% CI: 36.1-51.4%) and 41.9% (95% CI: 37.2-46.8%), respectively.

CONCLUSION

Due to the high prevalence of HPV infection, particularly with high-risk types, FSWs have a great susceptibility to the development of cervical and vaginal cancers. Furthermore, they can transmit their infection to their clients, which may result in a high prevalence of HPV and the incidence of HPV-associated malignancies among the general population.

Adjuvant Human Papillomavirus Vaccine to Reduce Recurrent Cervical Dysplasia in Unvaccinated Women: A Systematic Review and Meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis evaluating the efficacy of adjuvant human papillomavirus (HPV) vaccination in preventing recurrent cervical intraepithelial neoplasia (CIN) 2 or greater after surgical excision.

DATA SOURCES

Electronic databases (Cochrane, PubMed, EMBASE, MEDLINE, Scopus, and ClinicalTrials.gov) were searched for studies comparing surgical excision alone to surgical excision with adjuvant HPV vaccination for CIN 2 or greater. Studies published from January 1990 to January 2019 were included.

METHODS

A total of 5,901 studies were reviewed. The primary outcomes evaluated included: recurrence of CIN 2 or greater, CIN 1 or greater, and HPV 16,18 associated CIN within 6-48 months. We used Covidence software to assist with screening, and meta-analysis was performed using Review Manager.

TABULATION, INTEGRATION, AND RESULTS

Six studies met inclusion criteria and were included in the final analysis. In total 2,984 women were included; 1,360 (45.6%) received adjuvant HPV vaccination after surgical excision, and 1,624 (54.4%) received either placebo or surgical management alone for CIN 2 or greater. Recurrence of CIN 2 or greater occurred within 6-48 months in 115 women (3.9%) overall; however, recurrence was significantly lower for vaccinated women: 26 of 1,360 women (1.9%) vs 89 of 1,624 unvaccinated women (5.9%) (relative risk [RR] 0.36 95% CI 0.23-0.55). The risk of CIN 1 or greater was also significantly lower with adjuvant HPV vaccination, occurring in 86 of 1,360 vaccinated women (6.3%) vs 157 of 1,624 unvaccinated women (9.7%) (RR 0.67 95% CI 0.52-0.85). Thirty-five women developed recurrent CIN 2 or greater lesions specific to HPV 16,18; nine received adjuvant vaccination (0.9%) vs 26 who were unvaccinated (2.0%) (RR 0.41 95% CI 0.20-0.85).

CONCLUSION

Adjuvant HPV vaccination in the setting of surgical excision for CIN 2 or greater is associated with a reduced risk of recurrent cervical dysplasia overall and a reduction in the risk of recurrent lesions caused by the most oncogenic strains (HPV 16,18). Human papillomavirus vaccination should therefore be considered for adjuvant treatment in patients undergoing surgical excision for CIN 2 or greater.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42019123786.

Investigation on Spontaneous Abortion and Human Papillomavirus Infection

Viral infections are considered to be risk factors for spontaneous abortion (SA). Conflicting results have been reported on the association between Human Papillomavirus (HPV) and SA. HPV DNA was investigated in matched chorionic villi tissues and peripheral blood mononuclear cells (PBMCs) from women who experienced SA (n = 80, cases) and women who underwent a voluntary interruption of pregnancy (VI; n = 80, controls) by qualitative PCR and quantitative droplet digital PCR (ddPCR). Viral genotyping was performed using real-time PCR in HPV-positive samples. Specific IgG antibodies against HPV16 were investigated in sera from SA (n = 80) and VI (n = 80) females using indirect ELISA assays. None of the DNA samples from SA subjects was HPV-positive (0/80), whilst HPV DNA was detected in 2.5% of VI women (p > 0.05), with a mean viral DNA load of 7.12 copy/cell. VI samples (n = 2) were found to be positive for the HPV45 genotype. The ddPCR assay revealed a higher number of HPV-positive samples. HPV DNA was detected in 3.7% and 5% of SA and VI chorionic tissues, respectively, with mean viral DNA loads of 0.13 copy/cell in SA and 1.79 copy/cell in VI (p >0.05) samples. All DNA samples from the PBMCs of SA and VI females tested HPV-negative by both PCR and ddPCR. The overall prevalence of serum anti-HPV16 IgG antibodies was 37.5% in SA and 30% in VI (p > 0.05) women. For the first time, HPV DNA was detected and quantitatively analyzed using ddPCR in chorionic villi tissues and PBMCs from SA and VI women. Circulating IgG antibodies against HPV16 were detected in sera from SA and VI females. Our results suggest that HPV infection in chorionic villi may be a rare event. Accordingly, it is likely that HPV has no significant role in SA.

The quadrivalent HPV vaccine is protective against genital warts: a meta-analysis

BACKGROUND

The quadrivalent human papillomavirus (HPV) vaccine has been assumed to give protection against genital warts (GW) as well as cervical cancer. Our main question was whether HPV vaccine has any effects on the prevention of GW reported in randomised controlled clinical trials (RCTs) and time-trend analyses.

METHODS

This meta-analysis was performed according to the PRISMA guidelines using the PICO format. We searched in three electronic databases (PubMed, Embase, Cochrane Trials), and assessed heterogeneity using the Q-test and I-squared statistics, meta-regression was also performed. Odds ratios (OR) and their confidence intervals (CI) were calculated. The sensitivity was tested by leave-one-out method. We evaluated the presence of publication bias using the funnel plot graph and the Copas selection model. The strength of evidence was assessed using the GRADE approach.

RESULTS

Eight RCTs (per-protocol populations) and eight time-trend ecological studies were included in this meta-analysis. A significant reduction (pooled OR = 0.03, 95% CI: 0.01-0.09; I-squared = 53.6%) of GW in young women was recorded in RCTs, and in time-trend analyses both in young women (pooled OR = 0.36, CI 95% = 0.26-0.51; I-squared = 98.2%), and in young men (pooled OR = 0.69, 95% CI = 0.61-0.78; I-squared = 92.7%). In subgroup analysis, a significant reduction of the number of GW events was observed especially in women under 21 years (pooled OR = 0.33, 95% CI = 0.17-0.63). Leave-one-out analysis showed that similar results could be obtained after excluding one study, meta-regression did not show significant difference.

CONCLUSIONS

Prophylactic, quadrivalent HPV vaccination can prevent GW in healthy women and men, therefore, it should be included in routine immunization programme.

Virus Like Particles (VLP) as multivalent vaccine candidate against Chikungunya, Japanese Encephalitis, Yellow Fever and Zika Virus

Mosquito borne viral diseases are an emerging threat as evident from the recent outbreak of Zika virus (ZIKV) as well as repeated outbreaks of Chikungunya (CHIKV), Yellow fever (YFV) and Japanese encephalitis (JEV) virus in different geographical regions. These four arboviruses are endemic in overlapping regions due to the co-prevalence of the transmitting mosquito vector species Aedes and Culex. Thus, a multivalent vaccine that targets all four viruses would be of benefit to regions of the world where these diseases are endemic. We developed a potential Virus Like Particle (VLP) based multivalent vaccine candidate to target these diseases by using stable cell lines that continuously secrete VLPs in the culture supernatants. Moreover, inclusion of Capsid in the VLPs provides an additional viral protein leading to an enhanced immune response as evident from our previous studies with ZIKV. Immunization of Balb/c mice with different combinations of Capsid protein containing VLPs either as monovalent, bivalent or tetravalent formulation resulted in generation of high levels of neutralizing antibodies. Interestingly, the potential tetravalent VLP vaccine candidate provided strong neutralizing antibody titers against all four viruses. The 293 T stable cell lines secreting VLPs were adapted to grow in suspension cultures to facilitate vaccine scale up. Our stable cell lines secreting individual VLPs provide a flexible yet scalable platform conveniently adaptable to different geographical regions as per the need. Further studies in appropriate animal models will be needed to define the efficacy of the multivalent vaccine candidate to protect against lethal virus challenge.

Positivity and prevalence of human papillomavirus among a large population of women in southeastern China

Objective

To formulate strategies for prevention of cervical cancer, we investigated the prevalence of human papillomavirus (HPV) infection and the age-specific distribution among female participants in southeastern China.

Methods

From January 2016 to July 2018, 36,871 women from Meizhou People’s Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University were enrolled in this prospective study. HPV genotypes were detected using Luminex technology.

Results

HPV infection was observed in 18.34% of the participants, and 79.98% were infected with high-risk HPVs. The five most prevalent genotypes were HPV52 (18.18%), HPV16 (16.06%), HPV58 (11.37%), HPV53 (8.82%), and HPV39 (6.42%). The 9-valent HPV vaccine efficiently reduced the HPV infection rate by more than 10%, which is twofold the rate of other vaccines. Most HPV infections were observed in women age 40 to 49 years, and those age 30 to 59 years accounted for 79.62% of positive patients.

Conclusion

Our findings regarding HPV genotypes and the age-specific distribution of HPV infection in the study area will contribute to the development of cervical cancer screening programs and vaccine strategies.

Human papillomavirus vaccination: The ESGO-EFC position paper of the European society of Gynaecologic Oncology and the European Federation for colposcopy

Vaccines against human papillomavirus (HPV) are available in Europe since 2006. They have been highly effective in preventing infection and disease caused by the vaccine types. Clinical efficacy data are available for cervical, vulvovaginal and anal precancer and invasive cervical cancer. Disease reduction is best with early vaccination and a coverage of more than 70%. Gender-neutral vaccination provides direct protection for all men and improves the coverage. A good coverage is followed by herd protection of the unvaccinated men and women. School-based programs appear to be most effective; under the age of 15 years, two doses with an interval of 6-12 months are sufficient. From the age of 15 years, the standard regimen with three doses is recommended. A broad catch-up program for young adult women and men improves the effectiveness. The vaccines are also effective in sexually active women and men with previous but cleared infections. Vaccination in addition to local treatment of HPV-related disease appears to reduce recurrent or subsequent HPV-related disease. Combination of HPV vaccination and screening with HPV testing is the most effective approach to prevention of cervical cancer. The screening intervals may increase in the vaccinated cohorts. The upper age limit for vaccination remains to be evaluated, is country specific and depends on cost-effectiveness. The European Society of Gynaecologic Oncology and the European Federation for Colposcopy strongly support gender-neutral vaccination programs for children and young adolescents, with a catch-up program for young adults.

Human Papillomavirus E6 biosensing: Current progression on early detection strategies for cervical Cancer

Prognosis of early cancer detection becomes one of the tremendous issues in the medical health system. Medical debates among specialist doctor and researcher in therapeutic approaches became a hot concern for cervix cancer deficiencies early screening, risk factors cross-reaction, portability device, rapid and free labeling system. The electrical biosensing based system showed credibility in higher specificity and selectivity due to hybridization of DNA duplex between analyte target and DNA probes. Electrical DNA sensor for cervix cancer has attracted too many attentions to researcher notification based on high performance, easy to handle, rapid system and possible to miniaturize. This review explores the current progression and future insignificant for HPV E6 genobiosensing for early Detection Strategies of Cervical Cancer.

African-American parents' and daughters' beliefs about HPV infection and the HPV vaccine

OBJECTIVE

To increase our understanding about the health beliefs of African-American parents and their daughters toward HPV infection and HPV vaccine acceptance.

METHODS

The Health Belief Model was used as a guiding framework. Principles of grounded theory, theoretical sampling, and constant comparison analysis were used to qualitatively analyze data generated from personal interviews of African-American parents (n = 30) and their 12- to 17-year-old daughters (n = 34).

RESULTS

Mothers and daughters perceived low susceptibility to HPV infection and perceived the HPV vaccine as beneficial in protecting against genital warts and cervical cancer. Compared to daughters, parents placed particular emphasis on the vaccine's protection against genital warts. A major HPV vaccine acceptance barrier among parents and daughters was the politicization of the HPV vaccine by government figures. In addition, concerns about unknown side effects, safety, and effectiveness of HPV vaccination emerged. Cues to action varied among parents and daughters, and self-efficacy was higher among parents than daughters.

CONCLUSION

Understanding the health beliefs that promote HPV vaccine acceptance, while identifying and addressing beliefs that are barriers among parents and daughters, will assist in the development of appropriate HPV vaccine promotion initiatives for African-American parents and daughters.

Recommendations and barriers to vaccination in systemic lupus erythematosus

Patients with Systemic Lupus Erythematosus (SLE) pose a unique dilemma pertaining to immunization against common pathogens. SLE patients are usually not immunized with vaccines based on the fear of either precipitating infection in this immunosuppressed patient population (with live vaccines) or aggravating autoimmunity and hence lupus flares (with any vaccines). However, elevated vulnerability to infection makes patients with SLE precisely the population that needs protection from vaccine-preventable diseases. A summary of guidelines from the Centers for Disease Control and Prevention, professional societies, review articles and expert opinions regarding use of individual vaccines applicable to adults with SLE is presented in this review.

Predictors of Human Papillomavirus Vaccine Follow-Through Among Privately Insured US Patients

OBJECTIVES

To assess predictors of timely human papillomavirus (HPV) vaccine follow-through among privately insured individuals initiating the 3-dose series.

METHODS

Using MarketScan Commercial claims data, we identified 1 332 217 privately insured US individuals aged 9 to 26 years who initiated the bivalent or quadrivalent HPV vaccine series from 2006 to 2014, with follow-up data extending through 2015. The study outcome was receipt of third HPV dose within 12 months of the first, compared by year of initiation. Control variables were age, region, insurance plan type, provider type, and seasonal influenza vaccination.

RESULTS

Timely HPV vaccine follow-through fell over time. The trend was especially pronounced for females (from 67% in 2006 to 38% in 2014), but was also present for males (from 36% in 2011 to 33% in 2014). Similar patterns were present when we controlled for patient and provider characteristics or used alternative definitions of follow-through. Other positive predictors of timely follow-through included receipt of flu vaccine in the prior year and receipt of first HPV vaccine dose from an obstetrician/gynecologist.

CONCLUSIONS

HPV vaccine follow-through is low and has declined over time.

The Impact of Human Papilloma Viruses, Matrix Metallo-Proteinases and HIV Protease Inhibitors on the Onset and Progression of Uterine Cervix Epithelial Tumors: A Review of Preclinical and Clinical Studies

Infection of uterine cervix epithelial cells by the Human Papilloma Viruses (HPV) is associated with the development of dysplastic/hyperplastic lesions, termed cervical intraepithelial neoplasia (CIN). CIN lesions may regress, persist or progress to invasive cervical carcinoma (CC), a leading cause of death worldwide. CIN is particularly frequent and aggressive in women infected by both HPV and the Human Immunodeficiency Virus (HIV), as compared to the general female population. In these individuals, however, therapeutic regimens employing HIV protease inhibitors (HIV-PI) have reduced CIN incidence and/or clinical progression, shedding light on the mechanism(s) of its development. This article reviews published work concerning: (i) the role of HPV proteins (including HPV-E5, E6 and E7) and of matrix-metalloproteinases (MMPs) in CIN evolution into invasive CC; and (ii) the effect of HIV-PI on events leading to CIN progression such as basement membrane and extracellular matrix invasion by HPV-positive CIN cells and the formation of new blood vessels. Results from the reviewed literature indicate that CIN clinical progression can be monitored by evaluating the expression of MMPs and HPV proteins and they suggest the use of HIV-PI or their derivatives for the block of CIN evolution into CC in both HIV-infected and uninfected women.

Human Papillomavirus Prophylactic Vaccination improves reproductive outcome in infertile patients with HPV semen infection: a retrospective study

In this study we aimed to evaluate the effect on reproductive outcome of HPV vaccination in male subjects of infertile couples with HPV semen infection. In this single-center study, we retrospectively enrolled 151 infertile couples with detection of HPV in semen, attending our Hospital Unit of Andrology between January 2013 and June 2015, counseled to receive adjuvant HPV vaccination. Seventy-nine accepted vaccination (vaccine group) whilst 72 did not (control group). Our protocol of follow-up, aimed to evaluate HPV viral clearance, consisted in semen analysis, INNO-LiPA and FISH for HPV in semen cells after 6 and 12 months from basal evaluation. Spontaneous pregnancies, miscarriages and live births were recorded. Progressive sperm motility and anti-sperm antibodies were improved in the vaccine group at both time points (p < 0,05 vs control arm). Forty-one pregnancies, 11 in the control group and 30 in the vaccine group, were recorded (respectively 15% and 38,9%, p < 0,05) and resulted into 4 deliveries and 7 miscarriages (control group) and 29 deliveries and one miscarriage (vaccine group, p < 0,05 vs control group). HPV detection on sperms was predictive of negative pregnancy outcome. Adjuvant vaccination associated with enhanced HPV healing in semen cells and increased rate of natural pregnancies and live births.

Expanded strain coverage for a highly successful public health tool: Prophylactic 9-valent human papillomavirus vaccine

Human papillomavirus is considered the causative factor for cervical cancer, which accounts for approximately 5% of the global cancer burden and more than 600,000 new cases annually that are attributable to HPV infection worldwide. The first-generation prophylactic HPV vaccines, Gardasil® and Cervarix®, were licensed approximately a decade ago. Both vaccines contain the most prevalent high-risk types, HPV16 and 18, which are associated with 70% of cervical cancer. To further increase the type coverage, 5 additional oncogenic HPV types (31, 33, 45, 52 and 58) were added to the existing Gardasil-4 to develop a 9-valent HPV vaccine (9vHPV), Gardasil 9®, increasing the potential level of protection from ∼70% to ∼90%. The efficacy of the vaccine lies primarily in its ability to elicit type-specific and neutralizing antibodies to fend off the viral infection. Therefore, type-specific and neutralizing murine monoclonal antibodies (mAbs) were used to quantitate the antigenicity of the individual vaccine antigens and to measure the antibody levels in the serum samples from vaccinees in a type- and epitope-specific manner in a competitive immunoassay. Assays for 9vHPV are extended from the proven platform used for 4vHPV by developing and adding new mAbs against the additional types. In Phase III clinical trials, comparable safety profile and immunogenicity against the original 4 types were demonstrated for the 9vHPV vaccine, and these were comparable to the 4vHPV vaccine. The efficacy of the 9vHPV vaccine was established in trials with young women. Immunobridging for younger boys and girls was performed, and the results showed higher immunogenicity in the younger age group. In a subsequent clinical trial, the 2-dose regimen of the 9vHPV vaccine used among girls and boys aged 9-14 y showed non-inferior immunogenicity to the regular 3-dose regimen for young women (aged 16-26 years). Overall, the clinical data and cost-effectiveness analysis for the 9vHPV vaccine support its widespread use to maximize the impact of this important, life-saving vaccine.

Targeting Persistent Human Papillomavirus Infection

While the majority of Human papillomavirus (HPV) infections are transient and cleared within a couple of years following exposure, 10-20% of infections persist latently, leading to disease progression and, ultimately, various forms of invasive cancer. Despite the clinical efficiency of recently developed multivalent prophylactic HPV vaccines, these preventive measures are not effective against pre-existing infection. Additionally, considering that the burden associated with HPV is greatest in regions with limited access to preventative vaccination, the development of effective therapies targeting persistent infection remains imperative. This review discusses not only the mechanisms underlying persistent HPV infection, but also the promise of immunomodulatory therapeutic vaccines and small-molecular inhibitors, which aim to augment the host immune response against the viral infection as well as obstruct critical viral-host interactions.

Genital HPV infection among heterosexual and homosexual male attendees of sexually transmitted diseases clinic in Beijing, China

Human papillomavirus (HPV) has been identified as etiologic agent of various cancers for both men and women. However, HPV vaccine has not been recommended for men in China by far. To provide more evidences to promote HPV vaccination among males at high-risk of infection, this study investigated genital HPV genotypes among male attendees of sexually transmitted disease (STD) clinic. Male attendees (⩾18 years old) were recruited from STD clinic of Beijing Ditan Hospital. Data on sociodemographic characteristics and self-reported sexual behaviors were collected based on questionnaire. Genital swab specimens were collected for HPV genotypes. Finally, a total of 198 eligible participants were included in the study. Nearly half of them were infected with at least one type of HPV. The prevalence of genital infection among participants with only heterosexual behaviors (50·91%, 56/110) was significantly higher than those with only homosexual behaviors (36·36%, 32/88) (P < 0·001). However, the distribution pattern of the most frequently observed HPV subtypes were found to be similar between these two subgroups. HPV31, HPV18, HPV16 and HPV58 were the most frequently identified high-risk types and HPV11, HPV6, HPV81 and HPV61 were the most frequently observed low-risk types. Our results, although need further verification by larger sample size, suggested that currently available HPV vaccines covered most prevalent HPV types observed in Chinese men. As HPV vaccine has been approved for application in females in China, molecular epidemiological studies and intervention studies among high-risk males should be promoted as well.

Platform technologies for modern vaccine manufacturing

Improved understanding of antigenic components and their interaction with the immune system, as supported by computational tools, permits a sophisticated approach to modern vaccine design. Vaccine platforms provide an effective tool by which strategically designed peptide and protein antigens are modularized to enhance their immunogenicity. These modular vaccine platforms can overcome issues faced by traditional vaccine manufacturing and have the potential to generate safe vaccines, rapidly and at a low cost. This review introduces two promising platforms based on virus-like particle and liposome, and discusses the methodologies and challenges.

Vaccines against human papillomavirus infections: protection against cancer, genital warts or both?

Since 2006, three vaccines against infections and disease caused by human papillomavirus (HPV) became available in Europe-in 2006 a quadrivalent HPV 6/11/16/18 vaccine, in 2007 a bivalent HPV 16/18 vaccine and in 2015 a nonavalent HPV 6/11/16/18/31/33/45/52/58 vaccine. HPV 16 and 18 are the most oncogenic HPV strains, causing about 70% of cervical and other HPV-related cancers, HPV 6 and 11 cause 85% of all genital warts. The additional types of the polyvalent vaccine account for about 20% of invasive cervical cancer and >35% of pre-cancer. The potential differences between these vaccines caused some debate. All three vaccines give a robust and long-lasting protection against the strains in the various vaccines. The promise of cross-protection against other types (i.e. HPV 31/33/45) and hence a broader cancer protection was not fulfilled because these observations were confounded by the vaccine efficacy against the vaccine types. Furthermore, cross-protection was not consistent over various studies, not durable and not consistently seen in the real world experience. The protection against disease caused by oncogenic HPV strains was not compromised by the protection against low-risk types causing genital warts. The most effective cancer protection to date can be expected by the nonavalent vaccine, data indicate a 97% efficacy against cervical and vulvovaginal pre-cancer caused by these nine HPV types.

Controlled Hybrid-Assembly of HPV16/18 L1 Bi VLPs in Vitro

Based on the helix4-exchanged HPV16 L1 and HPV18 L1, HPV16 L1 Bi and HPV18 L1 Bi, we have successfully realized the controlled hybrid-assembly of HPV16/18 L1 Bi VLPs (bihybrid-VLPs) in vitro. The bihybrid-VLPs were further confirmed by fluorescence resonance energy transfer (FRET) and complex-immunoprecipitation (Co-IP) assays. The ratio of 16 L1 Bi and 18 L1 Bi in bihybrid-VLPs was verified to be 3:5 based on a modified magnetic Co-IP procedure, when mixing 1 equiv pentamer in assembly buffer solution, but it changed with conditions. In addition, the bihybrid-VLPs showed identical thermal stability as that of normal VLPs, suggesting high potential in practical applications. The present study is significant because it modified one of the vital steps of virus life cycle at the stage of virus assembly, supplying a new approach not only to deepen structural insights but also a possibility to prepare stable, low-cost, bivalent antivirus vaccine. Furthermore, the controlled hybrid-assembly of bihybrid-VLPs in vitro provides suggestions for the design of effective multivalent hybrid-VLPs, being a potential to develop broad-spectrum vaccines for the prevention of infection with multiple types of HPV.

Healthcare providers' perspectives on the acceptability and uptake of HPV vaccines in Zimbabwe

BACKGROUND

Human papillomavirus (HPV) vaccines are a critical strategy in the prevention of cervical cancer, especially in countries like Zimbabwe where cervical cancer screening rates are low. In Zimbabwe, cervical cancer is the leading cause of cancer-related deaths in women but the HPV vaccine is not yet widely available. This study examined healthcare providers': (1) perceptions of current hospital practices and issues in cervical cancer prevention and treatment in Zimbabwe; (2) knowledge of HPV and HPV vaccines; and (3) perspectives on introducing HPV vaccination programs in Zimbabwe, including potential facilitators and barriers to successful implementation.

METHOD

In-depth semi-structured interviews were conducted at a rural hospital with 15 healthcare providers in Zimbabwe. Interviews included eight main questions and a number of additional probes that reflected the study's purpose. Data were analyzed using thematic analysis.

RESULTS

Participants reported that women are not consistently being screened for cervical cancer. There were generally low levels of knowledge about HPV and HPV vaccines, but participants asked many questions indicating a desire to learn more. Although they were highly supportive of implementing HPV vaccination programs in Zimbabwe, they also identified a number of likely psychosocial, cultural, and logistical barriers to successful implementation, including cost, vaccine schedule, and hospital infrastructure. However, participants also provided a number of culturally relevant solutions, including education and community engagement.

CONCLUSION

This study provides insight from healthcare providers about barriers to implementation and possible solutions that can be used by policy makers, practitioners, and other stakeholders to facilitate the successful implementation of forthcoming HPV immunization programs in Zimbabwe.

Comparison of methods using paraffin-embedded tissues and exfoliated cervical cells to evaluate human papillomavirus genotype attribution

Monitoring the attribution of human papillomavirus (HPV) genotypes to cervical precancerous lesions is essential in assessing the efficacy of HPV vaccines. To resolve the lack of studies comparing the HPV genotyping procedures used to estimate HPV genotype attribution, we undertook a retrospective cross-sectional study to determine the appropriate genotyping procedures for evaluating the potential efficacy of HPV vaccines. Three procedures, including two different genotyping methods, Clinichip HPV test (C-Chip) and modified GP5+/6+ PCR coupled to fluorescent bead sorter detection (MGP), using exfoliated cervical cells (C-Chip and C-MGP, respectively) or formalin-fixed paraffin-embedded tissues (F-MGP), were compared. The overall agreement in detecting high-risk HPV was 88.5-92.1% among the three procedures, and genotype-specific agreement was 83.9-100% for all pairwise comparisons. In cervical intraepithelial neoplasia grade 2/3 specimens, HPV16/18 attribution estimated with the hierarchical attribution method was consistent among the procedures: 52.3% (45/86) for C-Chip, 54.7% (47/86) for C-MGP, and 52.3% (45/86) for F-MGP (P = 0.81). HPV16/18/31/33/45/52/58 hierarchical attribution was 88.4% (76/86) with C-Chip, 86.0% (74/86) with C-MGP, and 83.7% (72/86) with F-MGP (P = 0.49). In cervical intraepithelial neoplasia grade 3 specimens, the corresponding hierarchical attribution was 96.4% (53/55) with C-Chip, 89.1% (49/55) with C-MGP, and 94.5% (52/55) with F-MGP (P = 0.27). Although F-MGP is theoretically a reliable method for determining HPV genotype attribution, it is acceptable to use C-Chip or C-MGP, coupled to the hierarchical attribution formula to correct the bias of multiple infections. These approaches using exfoliated cervical cells are practical for monitoring the efficacy of HPV vaccines.

HPV infection and vaccination in Systemic Lupus Erythematosus patients: what we really should know

Patients with Systemic Lupus Erythematosus (SLE) are at increased risk for infections. Vaccination is a powerful tool to prevent infections, even in immunocompromised patients. Most non-live vaccines are immunogenic and safe in patients with SLE, even if antibody titres are frequently lower than those of healthy controls. Human papillomavirus (HPV) infections are more prevalent in SLE patients when compared to the healthy population. Low-risk types of this virus cause anogenital warts, while high risk types are strongly related to pre-malignant cervical abnormalities and cervical cancer. HPV vaccines have been developed to prevent these conditions. Although little is known about HPV vaccination in SLE, few studies in patients with autoimmune rheumatic diseases (AIRDs) have shown that HPV vaccines are safe, and capable to induce an immunogenic response in this group of patients. To date, available data suggest that HPV vaccines can be given safely to SLE patients. Given the increased incidence of cervical abnormalities due to HPV in SLE patients, this vaccination should be encouraged.

Public health value of universal HPV vaccination

BACKGROUND

The story of Human Papillomavirus vaccination demands reflection not only for its public health impact on the prophylactic management of HPV disease, but also for its relevant economic and social outcomes. Greater than ever data confirm the efficacy and support the urge for effective vaccination plans for both genders before sexual debut.

METHODS

A review of previous experience in gender-restricted vaccination programs has demonstrated a lower effectiveness. Limiting vaccination to women might increase the psychological burden on women by confirming a perceived inequality between genders; and even if all women were immunized, the HPV chain of transmission would still be maintained through men.

RESULTS

The cost-effectiveness of including boys into HPV vaccination programs should be re-assessed in view of the progressive drop of the economic burden of HPV-related diseases in men and women due to universal vaccination. The cost of the remarkable increase in anal and oropharyngeal HPV driven cancers in both sexes has been grossly underestimated or ignored.

CONCLUSIONS

Steps must be taken by relevant bodies to achieve the target of universal vaccination. The analysis of HPV vaccination's clinical effectiveness vs. economic efficacy are supportive of the economic sustainability of vaccination programs both in women and men. In Europe, these achievements demand urgent attention to the social equity for both genders in healthcare. There is sufficient ethical, scientific, strategic and economic evidence to urge the European Community to develop and implement a coordinated and comprehensive strategy aimed at both genders and geographically balanced, to eradicate cervical cancer and other diseases caused by HPV in Europe. Policymakers must take into consideration effective vaccination programs in the prevention of cancers.