Is one dose of human papillomavirus vaccine as effective as three?: A national cohort analysis

Current status and future directions for the development of human papillomavirus vaccines

The development of human papillomavirus (HPV) vaccines has made substantive progress, as represented by the approval of five prophylactic vaccines since 2006. Generally, the deployment of prophylactic HPV vaccines is effective in preventing newly acquired infections and incidences of HPV-related malignancies. However, there is still a long way to go regarding the prevention of all HPV infections and the eradication of established HPV infections, as well as the subsequent progression to cancer. Optimizing prophylactic HPV vaccines by incorporating L1 proteins from more HPV subtypes, exploring adjuvants that reinforce cellular immune responses to eradicate HPV-infected cells, and developing therapeutic HPV vaccines used either alone or in combination with other cancer therapeutic modalities might bring about a new era getting closer to the vision to get rid of HPV infection and related diseases. Herein, we summarize strategies for the development of HPV vaccines, both prophylactic and therapeutic, with an emphasis on the selection of antigens and adjuvants, as well as implications for vaccine efficacy based on preclinical studies and clinical trials. Additionally, we outline current cutting-edge insights on formulation strategies, dosing schedules, and age expansion among HPV vaccine recipients, which might play important roles in addressing barriers to vaccine uptake, such as vaccine hesitancy and vaccine availability.

Evaluation of a single-dose HPV vaccine strategy for promoting vaccine, health, and gender equity

Although several countries have adopted a single-dose human papillomavirus (HPV) vaccination strategy, many other countries continue to include multiple doses in their vaccination programmes. There are ethical reasons to transition to a single-dose strategy. We discuss how a single-dose HPV vaccination strategy advances equity in three dimensions: vaccine equity, health equity, and gender equity. Adopting a single-dose strategy eases pressure on vaccine supply, lowers programme costs, and is easier to distribute. This change facilitates vaccine procurement and implementation programmes (contributing to vaccine equity) and reaching hard to reach people or populations (contributing to health equity). A lower number of cases of HPV-related diseases that stem from greater vaccine distribution reduces the burden on women, who are at a higher risk of HPV-related disease or who act as caregivers, which prevents them from accessing opportunities that contribute to their empowerment (contributing to gender equity). Thus, pursuing the single-dose HPV vaccination programme strategy is ethically desirable.

Molecular cloning, biophysical and in silico studies of Human papillomavirus 33 E2 DNA binding domain

Human papillomavirus 33, a high-risk HPV strain, is mainly responsible for HPV infection and cervical cancer in Asian countries. The E2 protein of HPV 33 is a DNA-binding protein that plays a crucial role in viral replication and transcription. We have cloned, overexpressed, and purified the DNA binding domain of the E2 protein. Size exclusion chromatography results suggested that the protein exists in a homodimeric state in the native form. Circular dichroism data showed that the protein has a higher content of β-sheet. The melting temperature obtained from differential scanning calorimetry is 52.59 °C, and the protein is stable at pH 8 and is in a dimeric form at basic pH. The protein is monomeric or unfolded at a very low pH. Chemical denaturation studies suggested that the protein denatured and dissociated simultaneously. The DNA binding activity of the protein was also confirmed and it showed binding affinity in the order of 106 M-1. The protein structure was modeled using homology modeling and other bioinformatic tools. The virtual screening and molecular dynamic simulation studies were performed to find compounds that can act as potent inhibitors against E2 DBD. This study expands the understanding of the conserved structural and binding properties of HPV33 E2 DBD and provides the first report on the characterization of the viral protein.Communicated by Ramaswamy H. Sarma.

The clinical effectiveness of one-dose vaccination with an HPV vaccine: A meta-analysis of 902,368 vaccinated women

BACKGROUND

The comprehensive effectiveness of the HPV vaccine has been widely acknowledged. However, challenges such as dosing adherence and limited budgets have led to delays in HPV vaccination implementation in many countries. A potential solution to these issues could lie in a one-dose vaccination with an HPV vaccine, as indicated by promising outcomes in multiple studies.

METHODS

In this systematic review and meta-analysis, we examine the comparative effectiveness of the one-dose vaccination with an HPV vaccine against two- and three-dose regimens. Our investigation focuses on clinical efficacy, encompassing the prevention of HPV16, HPV18, and hrHPV infections, HSIL or ASC-H incidence, and CIN2/3 incidence.

RESULTS

Our analysis suggests that a single-dose HPV vaccine may offer effectiveness on par with two- or three-dose schedules. This conclusion is drawn from its capacity to confer immunogenic protection for at least 8 years of follow-up, coupled with its ability to mitigate infections and pre-cancerous occurrences.

CONCLUSION

While our findings underscore the potential of the one-dose vaccination with an HPV vaccine, further research and prolonged study durations are necessary to establish robust evidence supporting this recommendation. As such, continued investigation will be critical for informing vaccination strategies.

Can prophylactic HPV vaccination reduce the recurrence of cervical lesions after surgery? Review and prospect

Women with HSIL typically undergo conization/LEEP to remove cervical lesions, but the risk of HSIL lesions returning after surgical treatment remains higher than in the general population. HPV vaccination is essential to prevent cervical cancer. However, the effect of prophylactic HPV vaccination on reducing the risk of recurrent cervical lesions after surgical treatment remains unclear. This review aims to analyze and summarize the latest literature on the role of prophylactic HPV vaccine in reducing the recurrence of cervical lesions after surgery in patients with HSIL, and to review and update the history, efficacy, effectiveness and safety of HPV vaccine, focusing on the current status of global HPV vaccine implementation and obstacles.

Public Health Approach in the Elimination and Control of Cervical Cancer: A Review

Public health experts worldwide have emphasized cervical cancer since it is a substantial global health burden primarily affecting women. This article thoroughly reviews the public health approach to eradicating and managing cervical cancer. The public health community seeks to lower the prevalence, morbidity, and mortality linked to this preventable disease by integrating primary prevention by means of vaccination against the human papillomavirus (HPV), secondary prevention using screening and early identification, and tertiary prevention through improved therapy and supportive care. In order to accomplish broad vaccination coverage and ultimately effectively prevent cervical cancer, it remains crucial to address obstacles to vaccine accessibility, reluctance, and fair distribution. Early identification and subsequent treatments depend greatly on cervical cancer screening programs. This study explores several screening methods, such as Papanicolaou (Pap) tests based on cytology and cutting-edge technologies like molecular assays and HPV detection. The detection of precancerous lesions and early-stage malignancies, permitting prompt treatment, has shown significant promise when integrating these technologies into coordinated population-based screening programs. The study also underlines the significance of addressing cervical cancer burden inequities, particularly in resource-constrained areas where access to preventative and curative care is constrained. Innovative and affordable methods for addressing marginalized groups are studied, including community-based outreach programs, mobile health technology, and local healthcare practitioners and community leaders in awareness campaigns. The research also examines improvements in cervical cancer treatment procedures, such as surgery, radiation, chemotherapy, and immunotherapy. It improves therapeutic efficacy and patient survival rates by incorporating various modalities into a multidisciplinary strategy. Highlighted palliative care and psychological support are crucial for patients who have advanced cervical carcinoma.

A single dose of quadrivalent HPV vaccine is highly effective against HPV genotypes 16 and 18 detection in young pregnant women eight years following vaccination: an retrospective cohort study in Fiji

Background

In 2008/9, Fiji vaccinated >30,000 girls aged 9-12 years with the quadrivalent human papillomavirus (4vHPV) vaccine coverage for at least one dose was >60% (one dose only was 14%, two dose only was 13%, three doses was 35%). We calculated vaccine effectiveness (VE) of one, two and three doses of 4vHPV against oncogenic HPV genotypes 16/18, eight years following vaccination.

Methods

A retrospective cohort study was undertaken (2015-2019) in pregnant women ≤23 years old, eligible to receive 4vHPV in 2008/9, with confirmed vaccination status. The study was restricted to pregnant women due to the cultural sensitivity of asking about sexual behavior in Fiji. For each participant a clinician collected a questionnaire, vaginal swab and genital warts examination, a median eight (range 6-11) years post vaccination. HPV DNA was detected by molecular methods. Adjusted VE (aVE) against the detection of vaccine HPV genotypes (16/18), the comparison group of non-vaccine genotypes (31/33/35/39/45/51/52/56/58/59/66/68), and genital warts were calculated. Covariates included in the adjusted model were: age, ethnicity and smoking, according to univariate association with any HPV detection.

Findings

Among 822 participants the prevalence of HPV 16/18 in the unvaccinated, one, two and three-dose groups were 13.3% (50/376), 2.5% (4/158), 0% (0/99) and 1.6% (3/189), respectively; and for the non-vaccine high-risk genotypes, the detection rate was similar across dosage groups (33.2%-40.4%, p = 0.321). The aVE against HPV 16/18 for one, two and three doses were 81% (95% CI; 48-93%), 100% (95% CI; 100-100%), and 89% (95% CI; 64-96%), respectively. Prevalence of HPV 16/18 was lower among women with longer time since vaccination.

Interpretations

A single dose 4vHPV vaccine is highly effective against HPV genotypes 16 and 18 eight years following vaccination. Our results provide the longest duration of protection for reduced dose 4vHPV schedule in a low- or middle-income country in the Western Pacific region.

Funding

This study was supported by the Bill & Melinda Gates Foundation and the Department of Foreign Affairs and Trade of the Australian Government and Fiji Health Sector Support Program (FHSSP). FHSSP is implemented by Abt JTA on behalf of the Australian Government.

Human papillomavirus (HPV) vaccination: a call for action in Italy

Human papillomavirus (HPV) is the most common sexually transmitted infection. The implementation of primary prevention aims to reduce the burden of HPV infection and HPV-related disease. However, HPV-related diseases are still a concern, even in high-income countries. Approximately 570 000 new cervical cancer cases are diagnosed in Italy every year. Prophylactic HPV vaccines have been developed to minimize the spread of HPV. Growing evidence supports the administration of HPV vaccines (even just one dose) in reducing the prevalence of HPV infection and HPV-related disease including cancers. HPV vaccines are characterized by a high level of efficacy (>95%) in women who are naïve to HPV; however, they do not increase clearance in patients with ongoing HPV infection. With more than 200 million doses administered to date, HPV vaccines are considered to be safe and effective at preventing HPV-related infections and cancers. In this review we aim to review the current evidence regarding HPV vaccination and to describe trends in HPV vaccination coverage in Italy. In Italy, vaccination against HPV has been included in the National Immunization Plan (NIP) since 2007-2008. Using data abstracted from the Italian Ministry of Health, we analyzed changes in HPV vaccination coverage. We observed that HPV vaccines are underutilized and coverage rates are decreasing. Looking at the target population (females and males aged 11-12 years) in Italy, a decrease in coverage rates was observed. A call for action, improved HPV awareness, and education are the key elements to enhance the widespread adoption of HPV vaccination.

Exploring monitoring strategies for population surveillance of HPV vaccine impact using primary HPV screening

Australia's cervical screening program transitioned from cytology to HPV-testing with genotyping for HPV16/18 in Dec'2017. We investigated whether program data could be used to monitor HPV vaccination program impact (commenced in 2007) on HPV16/18 prevalence and compared estimates with pre-vaccination benchmark prevalence. Pre-vaccination samples (2005-2008) (n = 1933; WHINURS), from 25 to 64-year-old women had been previously analysed with Linear Array (LA). Post-vaccination samples (2013-2014) (n = 2989; Compass pilot), from 25 to 64-year-old women, were analysed by cobas 4800 (cobas), and by LA for historical comparability. Age standardised pre-vaccination HPV16/18 prevalence was 4.85% (95%CI:3.81-5.89) by LA; post-vaccination estimates were 1.67% (95%CI:1.21-2.13%) by LA, 1.49% (95%CI:1.05-1.93%) by cobas, and 1.63% (95%CI:1.17-2.08%) for cobas and LA testing of non-16/18 cobas positives (cobas/LA). Age-standardised pre-vaccination oncogenic HPV prevalence was 15.70% (95%CI:13.79-17.60%) by LA; post-vaccination estimates were 9.06% (95%CI:8.02-10.09%) by LA, 8.47% (95%CI:7.47-9.47%) by cobas and cobas/LA. Standardised rate ratios between post-vs. pre-vaccination rates were significantly different for HPV16/18, non-16/18 HPV and oncogenic HPV: 0.34 (95%CI:0.23-0.50), 0.68 (95%CI:0.55-0.84) and 0.58 (95%CI:0.48-0.69), respectively. Additional strategies (LA for all cobas positives; combined cobas and LA results on all samples) had similar results. If a single method is applied consistently, it will provide important data on relative changes in HPV prevalence following vaccination.

Optimal allocation strategies for HPV vaccination introduction and expansion in China accommodated to different supply and dose schedule scenarios: A modelling study

BACKGROUND

A key barrier to cervical cancer elimination in China is low human papillomavirus (HPV) vaccine uptake, which is limited by supply constraints, high prices, and restriction to two/three-dose schedule. We explored optimal vaccination strategies for maximizing health and economic benefits accommodated to different supply and dose schedules.

METHODS

We evaluated different HPV vaccine strategies under 4 scenarios with different assumptions about vaccine availability and dose schedules. Each strategy involved different vaccine types, target ages, and modes of delivery. We used a previously validated transmission model to assess the health impact (cervical cancer cases averted), efficiency (number of doses needed to be given to prevent one case of cervical cancer [NND]), and value for money (incremental cost-effectiveness ratio [ICER] and return on investment [ROI]) of different strategies in Chinese females over a 100-year time horizon. All costs are expressed in 2021 dollars. We adopted a societal perspective and discounted quality-adjusted life-years (QALYs), costs and benefits by 3% annually for cost-effectiveness analysis and ROI calculation.

FINDINGS

In a supply-constrained and on-label use scenario, compared with no vaccination, two-dose routine vaccination of 14-year-olds would be the optimal, cost-saving strategy for a future national program (NNDs: 150-220, net cost saving: $15 164 million-$22 034 million, ROIs: 7-14, depending on vaccine type). If the one-dose schedule recommended by WHO is permitted in China, then reallocating the second dose from the routine cohorts to add a catch-up vaccination at 20-year-olds would be the most efficient strategy (NNDs: 73-107), and would be cost-saving compared with routine one-dose vaccination only (net cost saving: $4127 million-$6035 million, ROIs: 19-37). When supply constraints are lifted, scaling up vaccination in older females to 26 years could further expand the health benefits and still be cost-saving compared to maintaining the optimal vaccination strategy in the supply-constrained context.

INTERPRETATION

Our study provides timely evidence for the current and future HPV vaccination strategy planning in China, and may also be of value to other countries with supply and dose restrictions.

FUNDING

Bill & Melinda Gates Foundation; CAMS Innovation Fund for Medical Sciences (CIFMS).

Costs of delivering human papillomavirus vaccination using a one- or two-dose strategy in Tanzania

OBJECTIVE

As part of the Dose Reduction Immunobridging and Safety Study of Two HPV Vaccines in Tanzanian Girls (DoRIS; NCT02834637), the current study is one of the first to evaluate the financial and economic costs of the national rollout of an HPV vaccination program in school-aged girls in sub-Saharan Africa and the potential costs associated with a single dose HPV vaccine program, given recent evidence suggesting that a single dose may be as efficacious as a two-dose regimen.

METHODS

The World Health Organization's (WHO) Cervical Cancer Prevention and Control Costing (C4P) micro-costing tool was used to estimate the total financial and economic costs of the national vaccination program from the perspective of the Tanzanian government. Cost data were collected in 2019 via surveys, workshops, and interviews with local stakeholders for vaccines and injection supplies, microplanning, training, sensitization, service delivery, supervision, and cold chain. The cost per two-dose and one-dose fully immunized girl (FIG) was calculated.

RESULTS

The total financial and economic costs were US$10,117,455 and US$45,683,204, respectively, at a financial cost of $5.17 per two-dose FIG, and an economic cost of $23.34 per FIG. Vaccine and vaccine-related costs comprised the largest proportion of costs, followed by service delivery. In a one-dose scenario, the cost per FIG reduced to $2.51 (financial) and $12.18 (economic), with the largest reductions in vaccine and injection supply costs, and service delivery.

CONCLUSIONS

The overall cost of Tanzania's HPV vaccination program was lower per vaccinee than costs estimated from previous demonstration projects in the region, especially in a single-dose scenario. Given the WHO Strategic Advisory Group of Experts on Immunization's recent recommendation to update dosing schedules to either one or two doses of the HPV vaccine, these data provide important baseline data for Tanzania and may serve as a guide for improving coverage going forward. The findings may also aid in the prioritization of funding for countries that have not yet added HPV vaccines to their routine immunizations.

HPV vaccination: Intention to participate among female senior high school students in Ghana

INTRODUCTION

Cervical cancer is the second most common cancer and the second leading cause of cancer death among women in Ghana. HPV vaccination is expected to be added to the national vaccination schedule in 2023. This study aimed to: i) describe intentions to participate in HPV vaccination and ii) explore factors associated with vaccination intentions among female senior high school students in Ghana.

METHODS

Female students (aged 16-24) were recruited from 17 senior high schools in Ashanti Region. A cross-sectional anonymous self-report paper-and-pen survey assessed students' HPV vaccination intentions using three items, and a range of correlates (individual, parent/family, social networks, service provision). Descriptive statistics were calculated for vaccination intentions, and correlates of intention scores (where higher scores indicate stronger intentions) were explored with a linear mixed-effect model.

RESULTS

Of 2400 participants, 64% (95%CI: 62%, 67%) agreed with at least one vaccination intention item. Uncertainty and disagreement with at least one item were endorsed by 51% (95%CI: 49%, 53%) and 44% (95%CI: 42%, 46%) of students, respectively. One-quarter of the students (25%, 95%CI: 23%, 26%) agreed, 12% (95% 11%, 13%) disagreed, and 11% (95%CI: 10%,13%) indicated uncertainty, on all three vaccination intention items. Vaccination uptake was 4.5%. Students were likely to have higher vaccination intention scores if: they had stronger beliefs about vaccine effectiveness; vaccination was recommended by parents, religious leaders and service providers, and vaccinated peers; and it was free. Students were likely to have lower vaccination intention scores if they perceived barriers to vaccination (e.g., side effects).

CONCLUSIONS

While two-thirds of students had some intention to participate in HPV vaccination, vaccine hesitancy (i.e., uncertainty or disagreement) was apparent. Alongside the rollout of a free national vaccination programme, messaging about vaccination benefits and effectiveness targeting students, as well as parents, religious leaders, service providers and peers would be beneficial given their influential role in students' vaccination intentions.

Key ethical considerations to guide the adjudication of a single-dose HPV vaccine schedule

There is a high burden of human papillomavirus (HPV) associated cancers in low- and middle-income countries (LMICs). Reducing the recommended dosing schedule from two doses to one makes the vaccine schedule logistically simpler and lowers the cost. This could make the distribution of the current vaccine supply more equitable and lead to the protection of more people. However, the clinical trials studying the efficacy of a single-dose schedule have not yet delivered final results. Against this background, the question is whether a single-dose HPV vaccine recommendation is appropriate now, and if so, what are the ethical considerations of such a recommendation? We developed three ethical recommendations: (1) adopt a holistic view of evidence to justify policy decisions; (2) prioritize the reduction in global disparities in decision-making at all levels; and (3) be transparent in the reporting of how key stakeholder interests have shaped the collection and interpretation of the evidence, and ultimate decisions. The complex discussion regarding the HPV single-dose vaccine schedule highlights the need for in-depth engagement globally to improve our understanding of country-specific contexts, and how those contexts influence decisions regarding the HPV vaccine single-dose recommendation.

Human papillomavirus vaccination and cervical cancer risk

Persistent human papillomavirus infection is the central cause of cervical cancer, the leading cause of cancer death among women worldwide. Clear evidence from both randomized trials and population based studies shows that vaccination against human papillomavirus reduces the incidence of cervical pre-cancer. These data suggest that the vaccine reduces the incidence of cervical cancer. However, human papillomavirus vaccine coverage is inadequate in all countries, especially in low and middle income countries where disease burden is highest. Supply side strategies to improve coverage include increasing the availability of low cost vaccines, school located delivery, single dose vaccine schedules, and development of vaccines that do not need refrigeration. Demand side strategies include enhancing provider recommendations, correcting misinformation, and public awareness campaigns. The near elimination of cervical cancer is achievable through increased uptake of human papillomavirus vaccination and efforts to increase screening for cervical cancer, especially when enacted to reduce disparities in across the world.

Real-world impact and effectiveness of the quadrivalent HPV vaccine: an updated systematic literature review

INTRODUCTION

Human papillomavirus (HPV) infection, which poses significant disease burden, is decreasing following implementation of vaccination programs. Synthesized evidence on HPV vaccine real-world benefit was published in 2016. However, long-term impact of vaccination, and how vaccination programs influence infection rates and disease outcomes, requires further examination.

AREAS COVERED

We systematically reviewed observational studies on HPV vaccination within MEDLINE, EMBASE, and Google Scholar from 2016 to 2020, involving 14 years of follow-up data. We identified 138 peer-reviewed publications reporting HPV vaccine impact or effectiveness. Outcomes of interest included rates of infection at different anatomical sites and incidence of several HPV-related disease endpoints.

EXPERT OPINION

The expansion of HPV vaccination programs worldwide has led to a reduction in genital infection and significant decreases in incidence of HPV-related disease outcomes. Therefore, the WHO has set goals for the elimination of cervical cancer as a public health concern. To track progress toward this requires an understanding of the effectiveness of different vaccination initiatives. However, the impact on males, and potential benefit of gender-neutral vaccination programs have not been fully explored. To present an accurate commentary on the current outlook of vaccination and to help shape policy therefore requires a systematic review of available data.

The Indigenous Australian HPV Cohort Study 2; continuation 5 to 10 years: Study Protocol (Preprint)

BACKGROUND

Human papillomavirus (HPV) infection, a common sexually transmitted disease, is associated with cancers of the cervix, vulva, vagina, penis, anus, and head and neck. Oropharyngeal squamous cell carcinoma (OPSCC; throat cancer) is a type of cancer involving the head and neck area that is rapidly increasing across the globe. There are higher rates of OPSCC among Indigenous populations relative to non-Indigenous Australian populations, although the HPV-attributable fraction remains unknown. For the first time at a global level, we plan to extend an Indigenous Australian adult cohort to monitor, screen, and ultimately prevent HPV-associated OPSCC and to undertake extensive cost-effectiveness modelling around HPV vaccination.

OBJECTIVE

This study aims to (1) extend follow-up to a minimum of 7 years post recruitment to describe the prevalence, incidence, clearance, and persistence of oral HPV infection; and (2) conduct clinical examinations of the head and neck, oral cavity, and oropharynx and collect saliva samples for early-stage OPSCC testing.

METHODS

We will continue to implement a longitudinal design for the next study phase, where we will ascertain the prevalence, incidence, clearance, and persistence of oral HPV infection at 48, 60, and 72 months; undertake clinical examinations/saliva assessments to detect early-stage OPSCC; and refer for treatment. The primary outcome measures are changes in oral HPV infection status, biomarker measures of early HPV-related cancer, and clinical evidence of early-stage OPSCC.

RESULTS

Participant 48-month follow-up will commence in January 2023. The first results are expected to be submitted for publication 1 year after 48-month follow-up begins.

CONCLUSIONS

Our findings have potential to change the way in which OPSCC among Australian Indigenous adults is managed, with desired impacts including cost-savings on expensive cancer treatments; improved nutritional, social, and emotional outcomes; and improved quality of life for both Indigenous adults and the Indigenous community more broadly. Continuing a large, representative Indigenous adult cohort to track oral HPV infection and monitor early OPSCC is essential to yield critical information to include in the management armamentarium of health and well-being recommendations for Australia's First Nations.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/44593.

A 10-year systematic review of theory-driven approaches to increasing catch-up HPV vaccination rates among young adult males in colleges/university settings

OBJECTIVE

To describe rates and identify factors associated with human papillomavirus (HPV) vaccination among young adult males in college/university settings.

METHODS

Study was reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Five electronic databases were searched for empirical studies published between 2009 and 2019 and focused on predictors for HPV vaccine uptake. Studies' methodological quality scores ranged between 12 and 23 points.

RESULTS

Five hundred and ninety eight titles/abstracts and 154 full-text articles were screened. Eighteen studies were included for final analysis. Results depicted participants' attitude, perceived susceptibility, severity, benefits, and barriers in receiving HPV vaccine. Many participants did not perceive themselves to be susceptible to HPV infection, and barriers to receiving HPV vaccine outweighed benefits. HPV knowledge and vaccination rates were relatively low among respondents.

CONCLUSION

Prevention campaigns that increase knowledge, promote positive attitudes, change perception of susceptibility, and address barriers may result in higher HPV vaccination rates among males in college/university settings.

HPV vaccination coverage for pediatric, adolescent and young adult patients receiving care in a childhood cancer survivor program

Pediatric, adolescent and young adult patients undergoing cancer treatment and/or hematopoietic stem cell transplant are at increased risk for developing a secondary human papillomavirus (HPV)-associated malignancy. The objective of this study was to determine HPV vaccination coverage among individuals participating in a childhood cancer survivor program (CCSP). A retrospective cohort study was conducted among CCSP patients age 11–26 years attending a CCSP visit between 2014 and 2019. Survivors were age-, sex-, and race-matched 1:2 with controls without cancer. Data were abstracted from the electronic health record and state-based vaccination registry. Analysis was limited to Minnesota residents to minimize missing vaccination data. Survivorship care plans (SCPs) were reviewed for vaccine recommendations.

592 patients were included in the analyses (200 CCSP patients; 392 controls). By study design, mean age (18.4 years), race (72 % white), and sex (49 % female) were similar in the two groups. Among CCSP patients 22 % resided in a rural area compared to 3.8 % of controls. Vaccination coverage among CCSP patients was not statistically significantly different from controls [60.0 % vs 66.3 %, OR = 0.82, 95 % CI: (0.55, 1.23), p = 0.35]. Completion of 3 doses was not different between groups even though 3 doses is recommended for all CCSP patients regardless of age at initiation (28.5 % vs 30.1 %, p = 0.09). Only 8.0 % of SCPs recommended HPV vaccination.

Although patients participating in a CCSP did not have significantly different HPV vaccination coverage compared to controls, HPV vaccination initiation and 3-dose series completion are still suboptimal in a patient population at high-risk of a secondary HPV-associated cancer.

Can Adjuvant HPV Vaccination Be Helpful in the Prevention of Persistent/Recurrent Cervical Dysplasia after Surgical Treatment?—A Literature Review

Simple Summary

Primary prophylactic, early detection and the treatment of precancerous lesions are the main goals of cervical cancer screening. Despite effective surgical treatment methods, using loop electrosurgical excision procedures and conization, the overall risk of the recurrence of HSIL lesions remains at approximately 6.6%. There is increasing evidence of the potential role of HPV vaccines in the adjuvant setting and their impact on the reduction of disease recurrence. This review aims to analyze the up-to-date research concerning the use and efficacy of secondary human papilloma virus (HPV) vaccination as an adjuvant method to surgical treatment in patients diagnosed with cervical HSILs.

Abstract

Cervical cancer formation is preceded by precursor lesions, including low-grade squamous intraepithelial lesions (LSILs) and high-grade squamous intraepithelial lesions (HSILs), which are usually diagnosed in women of reproductive age. Despite the recent advanced diagnostic and treatment methods, including colposcopy, the loop electrosurgical excision procedure (LEEP), and surgical conization, the recurrence or residual disease affects as many as 6.6% of patients. The lesions are often associated with human papilloma virus (HPV) infection. As HPV persistence is the leading and only modifiable factor affecting the risk of progression of CIN lesions into high-grade cervical dysplasia and cancer, it has been proposed to conduct adjuvant vaccination in patients treated for high-grade cervical dysplasia. To date, no vaccine has been approved for therapeutic use in patients diagnosed with HSILs; however, attempts have been made to determine the use of HPV prophylactic vaccination to reduce recurrent HSILs and prevent cervical cancer. The aim of this review was to analyze the up-to-date literature concerning the possible use of secondary human papilloma virus (HPV) vaccination as an adjuvant method to surgical treatment in patients diagnosed with cervical HSILs. Adjuvant HPV vaccination after surgical treatment may reduce the risk of recurrent cervical dysplasia.

Human papillomavirus vaccine effectiveness by number of doses: Updated systematic review of data from national immunization programs

BACKGROUND

Human papillomavirus (HPV) vaccines were first licensed as a three-dose series. Two doses are now widely recommended in some age groups; there are data suggesting high efficacy with one dose. We updated a systematic literature review of HPV vaccine effectiveness by number of doses in observational studies.

METHODS

We searched Medline and Embase databases from January 1, 2007, through September 29, 2021. Data were extracted and summarized in a narrative synthesis. We also conducted quality assessments for bias due to selection, information, and confounding.

RESULTS

Overall, 35 studies were included; all except one were conducted within the context of a recommended three-dose schedule. Evaluations were in countries that used bivalent HPV vaccine (seven), quadrivalent HPV vaccine (27) or both (one). Nine evaluated effectiveness against HPV infection, ten anogenital warts, and 16 cervical abnormalities. All studies were judged to have moderate or serious risk of bias. The biases rated as serious would likely result in lower effectiveness with fewer doses. Investigators attempted to control for or stratify by potentially important variables, such as age at vaccination. Eight studies evaluated impact of buffer periods (lag time) for case counting and 10 evaluated different intervals between doses for two-dose vaccine recipients. Studies that stratified by vaccination age found higher effectiveness with younger age at vaccination, although differences were not all formally tested. Most studies found highest estimates of effectiveness with three doses; significant effectiveness was found among 28/29 studies that evaluated three doses, 19/29 that evaluated two doses, and 18/30 that evaluated one dose. Some studies that adjusted or stratified analyses by age at vaccination found similar effectiveness with three, two and one doses.

CONCLUSION

Observational studies of HPV vaccine effectiveness have many biases. Studies examining persons vaccinated prior to sexual activity and using methods to reduce sources of bias are needed for valid effectiveness estimates.

Single-dose HPV vaccine immunity: is there a role for non-neutralizing antibodies?

A single dose of human papillomavirus (HPV) vaccine against HPV infection (prerequisite for cervical cancer) appears to be as efficacious as two or three doses, despite inducing lower antibody titers. Neutralizing antibodies are thought to be the primary mediator of protection, but the threshold for protection is unknown. Antibody functions beyond neutralization have not been explored for HPV vaccines. Here, we discuss the immune mechanisms of HPV vaccines, with a focus on non-neutralizing antibody effector functions. In the context of single-dose HPV vaccination where antibody is limiting, we propose that non-neutralizing antibody functions may contribute to preventing HPV infection. Understanding the immunological basis of protection for single-dose HPV vaccination will provide a rationale for implementing single-dose HPV vaccine regimens.

HPV Vaccine Intent among Adult Women Receiving Care at Community Health Centers

Human papillomavirus (HPV) is a disease that exacts substantial costs in human life and public health expenditures. Fortunately, a vaccine exists that can mitigate these costs. This study reports the development and evaluation of the intervention designed to overcome these barriers by using culturally grounded narratives to promote HPV vaccination. Women's Stories (WS) targets women over the age of 18 and was originally successfully validated for use among college students resulting in NCI recognition. WS was adapted for touch pad delivery in Planned Parenthood clinics where a randomized clinical trial was conducted in 8 clinics in 3 cities. Two hundred seventeen women were randomly assigned to treatment and control, completing pretest and posttest surveys. This study examined data from the immediate posttest. An intent to treat analysis was conducted using a generalized linear mixed modeling approach using a multinomial link and accounting for repeated measures by site. Results demonstrate significant short-term effects on vaccine intentions and vaccine self-efficacy. When compared to control group participants, women in the treatment condition more likely to intend to get the shot today/the day of interview (p < 0.01), as well as in 1 (p < 0.01) and 6 (p < 0.01) months and had greater self-efficacy to receive the HPV vaccination (B = 0.54; p = 0.0002). These results are promising for the potential impact of the intervention in clinical settings as well as providing a model for overcoming lack of awareness and vaccine resistance in other segments of the population.

The Use of Medical Claims Data for Identifying Missed Opportunities for HPV Immunization Among Privately Insured Adolescents in the State of Iowa

BACKGROUND

Rates of adolescent human papillomavirus (HPV) vaccination remain low, despite decades of safety and effectiveness data. We sought to quantify the extent of missed opportunities (MOs) for HPV vaccination among adolescents ages 11 to 13 in Iowa and compare the number of these MOs by gender and rurality.

METHODS

Medical claims data from a midwestern insurance provider were used to calculate total numbers of MOs for HPV vaccination for adolescents with continuous health insurance enrollment between ages 11 and 13 (n = 14,505). We divided MOs into several categories: total, among non-initiators, occurring before initiation, occurring after the first dose, and occurring between first and last dose. Finally, we used t-tests to perform subgroup comparisons (urban vs. rural; male vs. female).

RESULTS

Over half of adolescents failed to initiate vaccination by age 13. The majority of MOs occurred prior to initiation. Urban adolescents had more MOs than rural counterparts and males tended to have more MOs than females. Females experienced significantly fewer overall MOs than males 5.98 (SD = 5.49) compared to 6.18 (SD = 6.04) for males. Additionally, among non-initiators, urban females had significantly more MOs overall (M = 7.13; SD = 6.41) compared to rural females (M = 6.58; SD = 5.51).

CONCLUSIONS

Results highlight the extent of MOs that occur at the critical time period between ages 11 and 13. A lack of opportunity was not the barrier to HPV vaccination, particularly among both males and urban adolescents. It will be critical for providers to use known strategies to reduce MOs and utilize all adolescent visits to ensure vaccination is completed by age 13.

HPV Vaccination in Women with Cervical Intraepithelial Neoplasia Undergoing Excisional Treatment: Insights into Unsolved Questions

Several questions regarding the role of vaccination in women treated for high-grade cervical intraepithelial lesion (HSIL) have not been clarified. One of the main queries is whether the time at which the vaccine is administered (before or after treatment) influences the protection against post-treatment HSIL. A second unanswered question is whether the vaccine has any effect in women with persistent HPV after treatment. We aimed to address these questions in a study of 398 women undergoing excisional treatment from July 2016 to December 2019. Vaccination was funded and offered to all women undergoing treatment. A total of 306 women (76.9%) accepted HPV vaccination (vaccinated group): 113 (36.9%) received the first dose before excision and 193 (63.1%) after the procedure. A total of 92 women (23.1%) refused the vaccine (non-vaccinated group). Women vaccinated before treatment showed a lower rate of post-treatment HSIL compared with non-vaccinated women (0.9% vs. 6.5%; p = 0.047). Among women with persistent HPV infection after treatment, those who had received the vaccine showed a lower prevalence of post-treatment HSIL than non-vaccinated women (2.6% vs. 10.5%; p = 0.043). In conclusion, this study shows that HPV vaccination before treatment reduces the prevalence of post-treatment HSIL and suggests that vaccination might even benefit women with persistent HPV after treatment.

HPV vaccination coverage: slightly improved two-dose schedule completion estimates and historical estimates lower on AIR than HPV Register

OBJECTIVE

To compare Australian Immunisation Register (AIR) human papillomavirus (HPV) vaccination coverage against historical data from the former National HPV Vaccination Program Register and estimate two-dose vaccination coverage.

METHODS

Cross-sectional analysis of registry data for adolescent birth cohorts (1998-2007). Denominator populations were Medicare enrolments (AIR) and ABS estimated resident populations (HPV register).

RESULTS

For adolescents aged <17 years, AIR coverage estimates were several percentage points lower than HPV register estimates due to a larger Medicare enrolment denominator. Completed course coverage (two or three valid doses) for 15-year-old females in 2020 was 81.5% and for males 78.6%, higher than completed course coverage in 15-year-olds in 2019 (79.7 and 76.8% respectively). First dose coverage was similar for Indigenous adolescents but course completion was lower, although improving over time. Course completion was slightly lower (3.5-5.7%) in areas of lowest socioeconomic status and greatest remoteness.

CONCLUSIONS

Coverage is slightly lower using AIR than HPV register estimates. Moving from three to two doses has slightly improved completion, likely due to the wider dose spacing, but equity gaps remain.

IMPLICATIONS FOR PUBLIC HEALTH

An ongoing focus on equity in vaccine delivery is needed. Systems, reminders and catch-up opportunities to ensure course completion remain important.

Impact of one and two human papillomavirus (HPV) vaccine doses on community-level HPV prevalence in South African adolescent girls: study protocol and rationale for a pragmatic before-after design

INTRODUCTION

Vaccines against human papillomavirus (HPV) are the key to controlling cervical cancer in low/middle-income countries (LMICs) where incidence is highest, but there have been limited data from these settings on programme impact on HPV prevalence, and none in a population with endemic HIV infection. Furthermore, for many LMICs, the currently recommended two-dose schedule is difficult to deliver at scale, so there is mounting interest in a single-dose schedule.

METHODS AND ANALYSIS

The Human Papillomavirus One and Two-Dose Population Effectiveness Study is a hybrid impact evaluation of the national South African HPV vaccination programme, which has targeted grade 4 girls aged at least 9 years in public schools with two doses of vaccine since 2014, and a single-dose vaccine 'catch-up' programme delivered in one district in 2019. Impacts of both schedules on the prevalence of type-specific HPV infection will be measured using repeat cross-sectional surveys in adolescent girls and young women aged 17-18 years recruited at primary healthcare clinics in the four provinces. A baseline survey in 2019 measured HPV prevalence in the cohort who were ineligible for vaccination because they were already above the target age or grade under either the national programme or the single-dose programme in the selected district. HPV prevalence surveys are repeated in 2021 in the selected district, and in 2023 in all four provinces. We will calculate prevalence ratios to compare the prevalence of HPV types 16 and 18 in the single-dose (2021) and two-dose (2023) cohorts, with the vaccine-ineligible (2019) cohort.

ETHICS AND DISSEMINATION

The project was approved by the University of the Witwatersrand Human Research Ethics Committee (HREC #181005), and the University of New South Wales HREC (#181-005). Findings will be disseminated through peer-reviewed journals, scientific meetings, reports and community forums.

Impact of a human papillomavirus vaccination programme within organized cervical cancer screening: cohort study

BACKGROUND

We assessed the effectiveness of an HPV vaccination programme in lowering cervical abnormality risk, and conferring herd protection.

METHODS

Retrospective cohort study using linked screening and vaccination administrative health data of the general population of Ancona Province, Italy. We included all female residents born in 1990-1993, eligible for catch-up HPV vaccination up to age 25y, and adhering to organised screening in 2015-2020 (n=4665). Cervical abnormalities rates were compared between: vaccinated and unvaccinated women, and cohorts with high and low vaccination uptake. Analyses were adjusted for age, country of birth, screening tests number, laboratory, and municipality average income. Main outcomes were ASC-US+ or LSIL+ Pap smears, and CIN1+ or CIN2+ histology.

RESULTS

Mean screening age was 26.6{plus minus}1.5 years, and 1,118 screened women (24.0%) were vaccinated (mean vaccination age 19.2{plus minus}1.5 years). The diagnosed cervical abnormalities were: 107 LSIL+ (2.3%), 70 CIN1+ (1.5%), and 35 CIN2+ (0.8%). The adjusted odds ratios of LSIL+, CIN1+ and CIN2+ among vaccinated vs unvaccinated women were, respectively: 0.55 (95% confidence interval 0.33-0.91), 0.43 (0.22-0.86), and 0.31 (0.11-0.91). Among the unvaccinated, those in the highest-uptake (45.3%) 1993 cohort, versus the last pre-vaccination 1990 cohort, showed AORs of LSIL+ and CIN1+ of 0.23 (0.10-0.50), and 0.22 (0.07-0.69), respectively.

CONCLUSIONS

In the first evaluation from Central Italy, catch-up HPV vaccination considerably reduced the risk of all cervical abnormalities diagnosed within organized screening, and conferred an elevated degree of herd protection among unvaccinated women.

IMPACT

The high protection conferred by HPV vaccination suggests the need to update cervical screening.

The effects of the national HPV vaccination programme in England, UK, on cervical cancer and grade 3 cervical intraepithelial neoplasia incidence: a register-based observational study

BACKGROUND

Human papillomavirus (HPV) immunisation with a bivalent vaccine (Cervarix) was introduced in England, UK, in Sept 1, 2008: routine vaccination was offered to girls aged 12-13 years with a catch-up programme for females aged 14-18 years in 2008-10. We quantified the early effect of this immunisation programme on cervical cancer and cervical carcinoma in situ, namely grade 3 cervical intraepithelial neoplasia (CIN3), registrations.

METHODS

In this observational study, we used an extension of the age-period-cohort Poisson model to estimate the relative risk of cervical cancer in three vaccinated cohorts compared with earlier cohorts that were not eligible for HPV vaccination. Data from a population-based cancer registry were extracted on Jan 26, 2021, and were assessed for diagnoses of cervical cancer and CIN3 from Jan 1, 2006 to June 30, 2019 in women aged 20-64 years and who were a resident in England. We used three vaccinated cohorts to account for differences in the school year in which the vaccine was offered and its national coverage. Adjustment for confounding was made using information on changes in cervical screening policy and historical events that affected cervical cancer incidence. Results were compared across models with different adjustments for confounders.

FINDINGS

We used data from a total of 13·7 million-years of follow-up of women aged 20 years to younger than 30 years. The estimated relative reduction in cervical cancer rates by age at vaccine offer were 34% (95% CI 25-41) for age 16-18 years (school year 12-13), 62% (52-71) for age 14-16 years (school year 10-11), and 87% (72-94) for age 12-13 years (school year 8), compared with the reference unvaccinated cohort. The corresponding risk reductions for CIN3 were 39% (95% CI 36-41) for those offered at age 16-18 years, 75% (72-77) for age 14-16 years, and 97% (96-98) for age 12-13 years. These results remained similar across models. We estimated that by June 30, 2019 there had been 448 (339-556) fewer than expected cervical cancers and 17 235 (15 919-18 552) fewer than expected cases of CIN3 in vaccinated cohorts in England.

INTERPRETATION

We observed a substantial reduction in cervical cancer and incidence of CIN3 in young women after the introduction of the HPV immunisation programme in England, especially in individuals who were offered the vaccine at age 12-13 years. The HPV immunisation programme has successfully almost eliminated cervical cancer in women born since Sept 1, 1995.

FUNDING

Cancer Research UK.

Human papillomavirus vaccines effectiveness to prevent genital warts: A population-based study using health system integrated databases, 2009-2017

OBJECTIVES

To assess the effectiveness of the HPV vaccines in preventing genital warts (GW) in women aged 14-23 years and to estimate the incidence of GW in the whole population aged from 14 to 65.

DESIGN

Population-based retrospective cohort study using real-world data from the Valencia health system Integrated Databases (VID).

STUDY POPULATION

All subjects aged 14-65 years residing in the Valencia Region during 2009-2017 (n = 4,492,724), including a cohort of 563,240 females aged 14-23 years followed-up for the vaccine effectiveness (VE) estimations.

MAIN OUTCOME MEASURES

Incident cases of GW defined as the first activation of GW-related codes (ICD-9-CM 078.11 or ICD-10-CM A63.0) in hospital, primary and specialized care during the study period. Adjusted VE was estimated as (1-Relative Risk (RR)) × 100 by a negative binomial Bayesian model.

RESULTS

There were 23,049 cases of GW in the overall population and 2,565 in the females' cohort 14-23 years old. The incidence rate (IR) (in 100,000 persons-year) was 69.1 (95% CI 68.21-69.99) in the population overall, being higher in men (72.73; 95% CI 71.45-74.04). The IR of GW was 104.08 (95% CI 100.79-108.94) in the cohort of young women. The RR of GW increased with age from 14 to 21 years, reaching a plateau from 21 to 23. The VE of a complete schedule was 74% (95% CrI 68-79) for quadrivalent HPV vaccine (HPV4v). No effectiveness was seen with a full vaccination course with the bivalent HPV vaccine (HPV2v) in girls up to 21 years old. GW IR tends to be higher in unvaccinated cohorts covered by HPV4v vaccine than in unvaccinated cohorts not covered by HPV4v vaccine.

CONCLUSIONS

A complete HPV4v vaccination schedule was 74% effective in reducing GW in our population. Our results also suggest an indirect protection to unvaccinated and HPV2v vaccinated girls.

Human papillomavirus vaccination in the European Union/European Economic Area and globally: a moral dilemma

While many European Union/European Economic Area (EU/EEA) countries recently expanded human papillomavirus (HPV) vaccination to boys, HPV vaccine supply is currently limited for girls in low- and middle-income countries (LMIC) that are severely affected by HPV.Globally, about 50% of countries have introduced HPV vaccination. Some LMIC with high burden of cervical cancer have not yet introduced HPV vaccination, or are reaching suboptimal vaccination coverage. While WHO issued a call for cervical cancer elimination in 2018, a global shortage of HPV vaccines is currently predicted to last at least until 2024.We reviewed national policies of EU/EEA countries and recommendations of the World Health Organization (WHO) Strategic Advisory Group of Experts on immunisation to discuss current challenges and dose-sparing options. Several EU/EEA countries have extended HPV vaccination to boys and the European Cancer Organisation has issued a resolution for elimination of all HPV-associated cancers in both sexes. The European Centre for Disease Prevention and Control concluded in its 2020 guidance that cost-effectiveness of extending routine vaccination to boys depends on several context-specific factors. The extension of HPV vaccination to boys in EU/EEA countries may affect global availability of vaccines. Temporary dose-sparing options could be considered during the COVID-19 post-pandemic period.

Vaccine efficacy against persistent human papillomavirus (HPV) 16/18 infection at 10 years after one, two, and three doses of quadrivalent HPV vaccine in girls in India: a multicentre, prospective, cohort study

BACKGROUND

A randomised trial designed to compare three and two doses of quadrivalent human papillomavirus (HPV) vaccine in adolescent girls in India was converted to a cohort study after suspension of HPV vaccination in trials by the Indian Government. In this Article, the revised aim of the cohort study was to compare vaccine efficacy of single dose to that of three and two doses in protecting against persistent HPV 16 and 18 infection at 10 years post vaccination.

METHODS

In the randomised trial, unmarried girls aged 10-18 years were recruited from nine centres across India and randomly assigned to either two doses or three doses of the quadrivalent HPV vaccine (Gardasil [Merck Sharp & Dohme, Whitehouse Station, NJ, USA]; 0·5 mL administered intramuscularly). After suspension of recruitment and vaccination, the study became a longitudinal, prospective cohort study by default, and participants were allocated to four cohorts on the basis of the number vaccine doses received per protocol: the two-dose cohort (received vaccine on days 1 and 180 or later), three-dose cohort (days 1, 60, and 180 or later), two-dose default cohort (days 1 and 60 or later), and the single-dose default cohort. Participants were followed up yearly. Cervical specimens were collected from participants 18 months after marriage or 6 months after first childbirth, whichever was earlier, to assess incident and persistent HPV infections. Married participants were screened for cervical cancer as they reached 25 years of age. Unvaccinated women age-matched to the married vaccinated participants were recruited to serve as controls. Vaccine efficacy against persistent HPV 16 and 18 infections (the primary endpoint) was analysed for single-dose recipients and compared with that in two-dose and three-dose recipients after adjusting for imbalance in the distribution of potential confounders between the unvaccinated and vaccinated cohorts. This trial is registered with ISRCTN, ISRCTN98283094, and ClinicalTrials.gov, NCT00923702.

FINDINGS

Vaccinated participants were recruited between Sept 1, 2009, and April 8, 2010 (date of vaccination suspension), and followed up over a median duration of 9·0 years (IQR 8·2-9·6). 4348 participants had three doses, 4980 had two doses (0 and 6 months), and 4949 had a single dose. Vaccine efficacy against persistent HPV 16 and 18 infection among participants evaluable for the endpoint was 95·4% (95% CI 85·0-99·9) in the single-dose default cohort (2135 women assessed), 93·1% (77·3-99·8) in the two-dose cohort (1452 women assessed), and 93·3% (77·5-99·7) in three-dose recipients (1460 women assessed).

INTERPRETATION

A single dose of HPV vaccine provides similar protection against persistent infection from HPV 16 and 18, the genotypes responsible for nearly 70% of cervical cancers, to that provided by two or three doses.

FUNDING

Bill & Melinda Gates Foundation.

An Evaluation of Dose-Related HPV Vaccine Effectiveness Using Central Registries in Michigan

BACKGROUND

Human papillomavirus (HPV) vaccine effectiveness (VE) evaluations provide important information for vaccination programs. We established a linkage between statewide central registries in Michigan to estimate HPV VE against in situ and invasive cervical lesions (CIN3+).

METHODS

We linked females in Michigan's immunization and cancer registries using birth records to establish a cohort of 773,193 women with known vaccination history, of whom 3,838 were diagnosed with CIN3+. Residential address histories from a stratified random sample were used to establish a subcohort of 1,374 women without CIN3+ and 2,900 with CIN3+ among continuous Michigan residents. VE and 95% confidence intervals (CI) were estimated using cohort and case-cohort methods for up-to-date (UTD) vaccination and incomplete vaccination with 1 and 2 doses, and stratified by age at vaccination.

RESULTS

Both analytic approaches demonstrated lower CIN3+ risk with UTD and non-UTD vaccination vs. no vaccination. The cohort analysis yielded VE estimates of 66% (95% CI, 60%-71%) for UTD, 33% (95% CI, 18%-46%) for 2 doses-not UTD, and 40% (95% CI, 27%-50%) for 1 dose. The case-cohort analysis yielded VE estimates of 72% (95% CI, 64%-79%) for UTD, 39% (95% CI, 10%-58%) for 2 doses-not UTD, and 48% (95% CI, 25%-63%) for 1 dose. VE was higher for vaccination at age <20 than ≥20 years.

CONCLUSIONS

The statewide registry linkage found significant VE against CIN3+ with incomplete HPV vaccination, and an even higher VE with UTD vaccination.

IMPACT

Future VE evaluations by number of doses for women vaccinated at younger ages may further clarify dose-related effectiveness.

The impact of HPV vaccination beyond cancer prevention: effect on pregnancy outcomes

While the benefits of human papillomavirus (HPV) vaccination relating to cervical cancer prevention have been widely documented, recent published evidence is suggestive of an impact on adverse pregnancy outcomes (APOs) in vaccinated mothers and their infants, including a reduction in rates of preterm births and small for gestational age infants. In this review, we examine this evidence and the possible mechanisms by which HPV vaccination may prevent these APOs. Large-scale studies linking HPV vaccination status with birth registries are needed to confirm these results. Potential confounding factors to consider in future analyses include other risk factors for APOs, and historical changes in both the management of cervical precancerous lesions and prevention of APOs. If confirmed, these additional benefits of HPV vaccination in reducing APO rates will be of global significance, due to the substantial health, social and economic costs associated with APOs, strengthening the case for worldwide HPV immunization.

Single-Dose Human Papillomavirus Vaccination in Low- and Middle-Income Countries-Time for Implementation?

Although cervical cancer is becoming a rare disease in high income regions, it is still a major health issue in low- and middle-income countries (LMICs). Cervical cancer develops after infection with a high-risk human papilloma virus (hrHPV), an infection against which vaccination has been possible since 2006. Large population immunization programs have been organized in many higher income countries, and yet they have not been implemented in most of the lower and middle-income nations. The cost of the vaccine, as well as the need for two doses impedes coverage in the most vulnerable groups. Studies are suggesting the efficacy of single dose vaccination, but so far only observational data are available while large, randomized, double-blind studies are still ongoing. In order to prevent and combat this disease, it is essential to inform the population of vaccination benefits and offer accessible programs in higher as well as low-and middle-income countries. In this commentary, we wish to focus our attention on the case for implementing single dose vaccination in lower- and middle-income nations.

Eliminating Cervical Cancer: Progress and Challenges for High-income Countries

In 2020, the World Health Organization launched a major initiative to eliminate cervical cancer globally. The initiative is built around the three key pillars of human papillomavirus (HPV) vaccination, cervical screening and treatment, with associated intervention targets for the year 2030. The '90-70-90' targets specify that 90% of adolescent girls receive prophylactic HPV vaccination, 70% of adult women receive a minimum twice-in-a-lifetime cervical HPV test and 90% receive appropriate treatment for preinvasive or invasive disease. Modelling has shown that if these targets are met, the elimination of cervical cancer, defined as fewer than four cases per 100 000 women per annum, will be achieved within a century. Many high-income countries are well positioned to eliminate cervical cancer within the coming decades, but few have achieved '90-70-90' and many challenges must still be addressed to deliver these critical interventions effectively. This review considers the current status of cervical cancer control in relation to each of the three elimination pillars in high-income countries and discusses some of the developments that will assist countries in reaching these ambitious targets by 2030.

Australia's Role in Pneumococcal and Human Papillomavirus Vaccine Evaluation in Asia-Pacific

Australian researchers have made substantial contributions to the field of vaccinology over many decades. Two examples of this contribution relate to pneumococcal vaccines and the human papillomavirus (HPV) vaccine, with a focus on improving access to these vaccines in low- and lower-middle-income countries (LLMICs). Many LLMICs considering introducing one or both of these vaccines into their National Immunisation Programs face significant barriers such as cost, logistics associated with vaccine delivery. These countries also often lack the resources and expertise to undertake the necessary studies to evaluate vaccine performance. This review summarizes the role of Australia in the development and/or evaluation of pneumococcal vaccines and the HPV vaccine, including the use of alternative vaccine strategies among countries situated in the Asia-Pacific region. The outcomes of these research programs have had significant global health impacts, highlighting the importance of these vaccines in preventing pneumococcal disease as well as HPV-associated diseases.

Modelling the impact of prevention strategies on cervical cancer incidence in South Africa

In 2020, the World Health Organisation (WHO) published a strategy to eliminate cervical cancer as a public health concern. In South Africa, despite having a national screening policy in place since 2000, diagnosed cervical cancer incidence has shown no signs of decline. We extend a previously developed individual-based model for human immunodeficiency virus (HIV) and human papillomavirus (HPV) infection to include progression to cervical cancer. The model accounts for future reductions in HIV incidence and prevalence and includes a detailed cervical cancer screening algorithm, based on individual-level data from the public health sector. We estimate the impact of the current prevention programme and alternative screening scenarios on cervical cancer incidence. The South African screening programme prevented 8600 (95%CI 4700-12 300) cervical cancer cases between 2000 and 2019. At current levels of prevention (status quo vaccination, screening, and treatment), age-standardised cervical cancer incidence will reduce from 49.4 per 100 000 women (95%CI 36.6-67.2) in 2020, to 12.0 per 100 000 women (95%CI 8.0-17.2) in 2120. Reaching WHO's prevention targets by 2030 could help South Africa reach elimination (at the 10/100 000 threshold) by 2077 (94% probability of elimination by 2120). Using new screening technologies could reduce incidence to 4.7 per 100 000 women (95%CI 2.8-6.7) in 2120 (44% probability of elimination at the 4/100 000 threshold). HPV vaccination and decreasing HIV prevalence will substantially reduce cervical cancer incidence in the long term, but improvements to South Africa's current screening strategy will be required to prevent cases in the short term. Switching to new screening technologies will have the greatest impact.

Cohort profile: indigenous human papillomavirus and oropharyngeal squamous cell carcinoma study - a prospective longitudinal cohort

PURPOSE

Our aims are to: (1) estimate prevalence, incidence, clearance and persistence of oral human papillomavirus (HPV) infection among Indigenous Australians; (2) identify risk factors associated with oropharyngeal squamous cell carcinoma (OPSCC)-related HPV types (HPV 16 or 18); (3) develop HPV-related health state valuations and; (4) determine the impact on OPSCC and cervical cancers, and the cost-effectiveness of extending publicly-funded HPV vaccination among Indigenous Australians.

PARTICIPANTS

Participants were recruited from February 2018 to January 2019. Twelve-month follow-up occurred from March 2019 to March 2020. Participants provided socio-demographic characteristics, health-related behaviours including tobacco and alcohol use and sexual history. Health state preferences in regard to HPV vaccination, knowledge regarding HPV infection, OPSCC and cervical cancer were collected using a two-stage standard gamble approach. Participants provided saliva samples and DNA for microbial genotyping was extracted.

FINDINGS TO DATE

Of the 910 participants who were positive for β-globin at baseline, 35% had any oral HPV infection. The most prevalent HPV types were 13 or 32 (Heck's disease; 23%). The second most prevalent types were associated with OPSCC (HPV 16 or 18; 3.3%). Of the 645 participants who were positive for β-globin at 12-month follow-up, 43% had any HPV infection. Of these, 33% were HPV types 13 or 32 and 2.5% were HPV 16 or 18. Some 588 participants had β-globin positive oral samples at baseline and 12-month follow-up. The prevalence of any oral HPV infection increased from 34% at baseline to 44% at 12-month follow-up; due to increases in HPV types 13 or 32 (20% at baseline and 34% at 12-month follow-up).

FUTURE PLANS

Further funding will be sought to continue follow-up of this cohort, and to include (after a full medical history) a thorough clinical examination of the external head and neck; a complete oral examination and examination of the oropharynx. Blood tests for early stage OPSCC will also be undertaken.

Long Noncoding RNA LINC00899/miR-944/ESR1 Axis Regulates Cervical Cancer Cell Proliferation, Migration, and Invasion

Cervical cancer (CC) is a common malignancy in women. Long noncoding RNA LINC00899 plays a role in cancer, but its effects in CC are unknown. Our experiment aims to investigate the specific effects of LINC00899 in CC. LINC00899 was lowly expressed in CC tissues and cells, and overexpressed LINC0089 inhibited the viability, proliferation, migration, and invasion of CC cells, whereas silencing of LINC00899 had the opposite effect. There is a targeting relationship between LINC0089 and miR-944. It was found that miR-944 could competitively bind with LINC00899, and LINC00899 in turn, could downregulate expression of miR-944. Moreover, estrogen receptor 1 (ESR1) was the target gene of miR-944. Overexpressed miR-944 inhibited ESR1 expression, yet enhanced the migration and invasion of CC cells and promoted the expression levels of N-cadherin and Vimentin while inhibiting the expression of E-cadherin. However, overexpressed ESR1 reversed the effect of miR-944 overexpression on CC cells. LINC00899/miR-944/ESR1 axis regulates the proliferation, migration, and invasion of CC cells by regulating the expression levels of related proteins.

Effective HPV vaccination coverage in Australia by number of doses and two-dose spacing: What if one or two doses are sufficient?

Background

Initially, three-dose schedules were recommended for vaccines against human papillomavirus (HPV); subsequently recommendations have been updated to a schedule of two doses delivered at least six (minimum five) months apart for those aged <15 years at dose 1. We aimed to re-estimate effective HPV vaccination coverage in Australia, considering reduced-dose schedules and possible one-dose effectiveness. We also aimed to identify which of the three school visits was most commonly missed amongst two-dose only recipients, to inform optimal timing of visits.

Methods

National vaccination register data were used to estimate: i) vaccination coverage at December 2017, either with a complete course (three or two sufficiently-spaced doses (>151 days apart)), or at least one dose; ii) for each birth cohort offered vaccination, the percentage of the initially targeted cohort with a complete course, or at least one dose (reflecting uptake at the time the vaccine was offered); and iii) among two-dose only recipients, the percentage who missed each of three school visits.

Results

Including those with two sufficiently-spaced doses increased end-2017 coverage by 1.3–2.8% points in those vaccinated at school. Including those with at least one dose increased coverage further, by 6.5–9.5% points, mostly due to including those receiving multiple too-closely-spaced doses. One-dose coverage reached 90.9% and 86.9% in females and males respectively born in 2002.

Among those vaccinated at school who received only two doses, it was much more common to miss the first (31.0% females; 32.5% males) or the third visit in the school year (54.6% females; 48.6% males) than the second (14.1% females; 18.8% males).

Conclusions

Including those with two sufficiently-spaced doses has a very modest impact on HPV vaccine coverage in Australia. If receiving at least one dose offers substantial protection, these data suggest that the school-based program is now achieving close to 90% coverage on this measure.

•

HPV coverage data in Australia does not take into account valid 2-dose courses.

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Including two sufficiently-spaced HPV doses had only a modest impact on coverage.

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Over 60% of 2-dose recipients had doses too closely spaced for a 2-dose schedule.

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One-dose coverage reached 90.9%/86.9% in females/males born in 2002.

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Two-dose only recipients most commonly missed the third or first school visit.

Human Papillomavirus Vaccination After COVID-19

The current global novel coronavirus disease 2019 (COVID-19) pandemic threatens to derail the uptake of human papillomavirus (HPV) vaccination in low- and lower-middle income countries with major disruptions to routine immunization and the introduction of new vaccines delayed. This has a major impact on the World Health Organization cervical cancer elimination strategy, where it is dependent on HPV vaccination as well as cervical cancer screening and treatment. We discuss current opportunities and barriers to achieve high uptake of HPV vaccination in low- and lower-middle income countries as well as the impact of COVID-19. Implementation of 4 key recommendations for HPV vaccination in low- and lower-middle income countries is needed: increased global financial investment; improved vaccine supply and accelerated use of a single-dose schedule; education and social marketing; and adoption of universal school-based delivery. With the commitment of the global health community, the adoption of these strategies would underpin the effective elimination of cervical cancer.

Surveillance systems for monitoring cervical cancer elimination efforts: Focus on HPV infection, cervical dysplasia, cervical screening and treatment

In order to achieve the global elimination of cervical cancer as a public health problem, close surveillance of progress in public health and clinical activities and outcomes across the three pillars of vaccination, screening and treatment will be required. Surveillance should ideally occur within an integrated system that is planned, funded, and regularly evaluated to ensure it is providing timely, accurate and relevant feedback for action. In this paper, we conceptualise the main public health surveillance objectives as process and outcome measures in each of the three pillars. Process measures include coverage/participation measures for vaccination, screening and treatment alongside the ongoing assessment of the quality and reach of these programs and activities. Outcome measures related to the natural history of human papillomavirus (HPV) infection include HPV infection prevalence, precursor cervical lesions and cervical cancers (including stage at diagnosis, cancer incidence and mortality). These outcome measures can be used for monitoring the effectiveness of the three core activities in the short, medium and long term to assess whether these interventions are effectively reducing their occurrence. We discuss possible methods for the surveillance of these measures in the context of country capacity, drawing from examples in Australia, the USA and in low and middle income countries.

Current and future vaccine clinical research with the licensed 2-, 4-, and 9-valent VLP HPV vaccines: What's ongoing, what's needed?

Prophylactic HPV vaccination has been a great public health success. For >20 years, clinical trials were conducted with the 2-, 4-, and/or 9-valent vaccines in young-adult females, mid-adult women, males, and adolescents. In all studies, the vaccines were highly efficacious, immunogenic, and well tolerated. Following vaccine licensure and utilization in national vaccine programs globally (real-world settings primarily in high income countries), numerous studies demonstrated that the vaccines continue to have an excellent safety profile and have dramatically reduced the incidence of genital warts, HPV vaccine-type prevalence, and precancerous lesions. Thirty-eight clinical trials with the currently licensed HPV vaccines are ongoing. Key questions being addressed in new trials include: efficacy against persistent infection and immunogenicity of a 1-dose regimen; efficacy of 3 doses in 20-45-year-old females; use in postpartum women and immunocompromised individuals (HIV, liver and kidney transplants); dose sparing via intradermal administration; use in combination with a PD1 monoclonal antibody in patients with cervical cancer; impact on recurrent disease in women undergoing cervical conization; persistence of protection; and use to prevent oropharyngeal cancer. Additional clinical research that should be conducted includes: long-term follow-up, particularly of 1- and 2-dose regimens; further evaluation of flexible 2-dose regimens; immunogenicity of 1- or 2-dose regimens in persons ≥15 years old and immunocompromised populations; safety and immunogenicity of 1 or 2 doses in children <9 years old; assessment of the vaccine in the prevention of transmission; interchangeability with newer HPV vaccines; additional concomitant use studies; and prevention of penile cancer and recurrent respiratory papillomatosis.

Effectiveness of HPV vaccination against the development of high-grade cervical lesions in young Japanese women

BACKGROUND

Although more than 10 years have passed since HPV vaccination was implemented, first as an interim programme (Emergent vaccine promotion programme) in November 2010, followed by incorporating into the National Immunization Programme in April, 2013 and suspended in June 2013, limited studies have investigated the HPV vaccine effectiveness against high-grade cervical lesions in Japan.

METHODS

We collected the matched data of the results of cervical biopsy and history of vaccination from the Japan Cancer Society database. The subjects were women aged 20 to 29 years screened for cervical cancer between April, 2015 and March, 2017, and with information on HPV vaccination status. We estimated the relative risk of developing high-grade cervical lesions in vaccinated subjects using Poisson regression as compared to unvaccinated subjects.

RESULTS

Among the 34,281 women screened, 3770 (11.0%) were vaccinated. The prevalence of CIN2+ was statistically significantly lower in the vaccinated women as compared to the unvaccinated women (Vaccine Effectiveness (VE) =76%; RR = 0.24, 95% CI:0.10-0.60). High VE against CIN3+ was also observed (91%; RR = 0.09, 95% CI:0.00-0.42).

CONCLUSION

Women aged 20-29 years who received at least one dose of HPV vaccine had a significantly lower risk of high-grade cervical lesions than those not vaccinated. In Japan, HPV vaccination should be resumed in order to reduce the incidence of cervical cancer.

One-Dose Human Papillomavirus Vaccination and the Risk of Genital Warts: A Danish Nationwide Population-based Study

BACKGROUND

Increasing evidence suggests that 1-dose human papillomavirus (HPV) vaccination may protect significantly against HPV-related disease. We provide nationwide, real-world data on the risk of genital warts (GWs) after <3 vaccine doses.

METHODS

All Danish women born in 1985-2003 were identified, and individual-level vaccination data were retrieved. The cohort was followed up for first occurrence of GWs until 31 December 2016. Using Poisson regression, we calculated incidence rates (IRs) of GWs per 100 000 person-years and IR ratios (IRRs) with corresponding 95% confidence intervals (CIs) for GWs, according to vaccination status, age at first dose, and calendar time.

RESULTS

The cohort comprised 1 076 945 girls and women, of whom 485 408 were vaccinated. For girls initiating vaccination at age 12-14 years and 15-16 years, 1-dose vaccine effectiveness (VE) was 71% (IRR = 0.29; 95% CI, .22-.38) and 62% (0.38; .29-.49), respectively, compared with unvaccinated girls. In the same age groups, 2-dose VE was 78% (IRR, 0.22; 95% CI, .18-.26) and 68% (0.32; .26-.38), respectively. After 2009, the IRRs for 3 versus 1 dose and 2 versus 1 dose increased towards unity over calendar time, being 0.69 (95% CI, .57-.84) and 0.86 (.68-1.08) in 2016, respectively.

CONCLUSIONS

In this study, 1 or 2 doses of quadrivalent HPV vaccine was associated with substantial protection against GWs in girls vaccinated at age ≤16 years. The 1-dose VE approached that of 3 or 2 doses over calendar time, probably reflecting the impact of herd protection.

Human papillomavirus vaccination: Good clinical practice recommendations from the Federation of Obstetric and Gynecological Societies of India

Human papillomavirus (HPV) vaccination offers an excellent prospect for the primary prevention of cervical cancer. The bivalent and quadrivalent vaccines are both available in India. The nonavalent vaccine is licensed but not yet available. However, there still remain controversies regarding the vaccination of older women, immunocompromised females and other special groups. To provide recommendations for HPV vaccination in India. The Federation of Obstetric and Gynecological Societies of India (FOGSI) convened an expert group on cervical cancer prevention to formulate good clinical practice recommendations (GCPR) with respect to vaccine efficacy and safety, target groups, optimal timing and dosing schedules. HPV vaccines are licensed for females aged 9-45 years in India and have been seen to be safe and effective. FOGSI recommends HPV vaccination of all girls <15 years of age as the best target group, in whom two-doses at an interval of 6 months, extendable to 18 months, are recommended. Three-doses are recommended in girls >15 years of age, immunocompromised persons and sexual assault survivors. Older women and women with abnormal screening results may be vaccinated with an understanding that vaccination does not protect against already acquired infections and screening has to continue. Single-dose vaccination results are promising. Increased awareness is required to reduce vaccine hesitancy. HPV vaccination should be the priority to achieve the elimination of cervical cancer. The introduction of affordable HPV vaccines and reduced dose schedules will improve coverage.