Effectiveness of prophylactic HPV vaccines against cervical abnormalities and HPV infection in Japan: The J-HERS 2021 multicenter study

This study investigated the efficacy of the prophylactic human papillomavirus (HPV) vaccine, which was initiated between 2009 and 2013 in Japan. The study involved 1529 eligible women aged 16-39 years who visited 11 outpatient clinics in Japan for various reasons. These patients underwent HPV genotype analysis and a Pap test of cervical cell samples. A total of 299 women (19.6%) had received the prophylactic HPV vaccine (bivalent:quadrivalent vaccine ratio = 2:1). Of the 5062 participants in the Japanese Human Papillomavirus Disease Education and Research Survey (J-HERS 2011), which was conducted in the pre-vaccination era, 3236 eligible participants were included as controls. In this study (J-HERS 2021), the highest rate of HPV vaccination (53%) was observed in patients aged 22-27 years. Vaccinated individuals exhibited a 49% rate of protection against low-grade intraepithelial lesions (LSILs) and atypical squamous cells, not excluding high-grade squamous intraepithelial lesions (ASCH) or worse (LSIL/ASCH+), and a 100% rate of protection against high-grade squamous intraepithelial lesions (HSILs) or worse (HSIL+). Significant reductions in HPV16 (95%) and HPV18 (100%) infections were noted, but no differences were observed in HPV6 and HPV11 infections. The prevalences of HPV51 and HPV59 increased with vaccination, although these changes were not confirmed in the comparative study with J-HERS 2011. Comparing the prevaccination (J-HERS 2011) and postvaccination (J-HERS 2021) periods, 43%, 51%, 88%, and 62% reductions in HPV16, HPV18, HPV16/18, and HPV31/58 infection rates were observed, respectively. Similarly, 62% and 71% reductions in LSIL/ASCH+ and HSIL+ rates were noted, respectively. There were 88% and 87% reductions in LSIL/ASCH+ and HSIL+ rates in 16-21- and 28-33-year-old patients, respectively. Bivalent or quadrivalent vaccines provided 100% protection against high-grade squamous cell lesions (suggestive of CIN2 or CIN3) in young women aged <39 years at 9-12 years after initiation of Japan's first nationwide HPV vaccination program. Cross-protection against HPV31 and HPV58 is likely to occur, although some HPV-type replacements are inconsistent across vaccination regimens. This demonstrates the effectiveness of the HPV vaccine. However, continuous monitoring of cervical cancer and precancer is necessary in younger generations (born 1997-2007), who were rarely vaccinated due to the prolonged suspension of the vaccine recommendations in Japan.

Knowledge, attitude, and practices regarding human papilloma virus vaccination among physicians in Qatar

BACKGROUND

The human papilloma virus is a global problem that affects sexually active women and men, with cervical cancer being the most serious associated disease. Most cervical cancer cases can be prevented by vaccination against the human papilloma virus early in life. The objective of this study was to assess the knowledge, attitudes, and practices among physicians working in Qatar, regarding the human papilloma virus, infection, and prevention using vaccines.

STUDY-DESIGN

This was a cross-sectional study using quantitative data collection.

METHODOLOGY

An online survey targeting physicians working in Qatar was conducted, using a web-based pretested questionnaire. The questionnaire comprised four sections capturing a few demographic details, 33 questions in the Knowledge Section, 12 questions eliciting the attitude, and 14 practice-related questions. Mean knowledge score was calculated and those with a score more than the mean score were considered to have sufficient knowledge. Association between knowledge and attitude/practices/independent variables were looked for using bivariate and multivariate analysis. Logistic regression was used to identify the predictors for recommending human papilloma virus vaccines.

RESULTS

Of the 557 physicians who participated, 83.7% had sufficient knowledge, but only 69.1% knew that human papilloma virus vaccines were available in Qatar. The majority (89.4%) knew that human papilloma virus infection could be asymptomatic and 96.1% knew at least one symptom; 77% believed the human papilloma virus vaccine would substantially decrease the chances of human papilloma virus infection and related cancers and 46.5% felt physicians were less motivated to promote the human papilloma virus vaccine. The perceived barriers to community acceptance of the human papilloma virus vaccine were lack of awareness regarding the relationship between human papilloma virus and cervical cancer (61.6%), doubts regarding efficacy (32.5%), fear regarding safety (26.9%), concern that the human papilloma virus vaccination may encourage risky sexual behavior (26.8%), and perceived low-risk (23.3%) and cost (24.6%). Only 21.5% commonly discussed sexual health with their clients. More than one-third were not interested in recommending the human papilloma virus vaccine. Bivariate analysis showed nationality, specialization, discussing with patients, and recommending vaccine to be significantly associated with knowledge. Bivariate and regression analysis identified that female gender and physician's religion were significant predictors to recommend the human papilloma virus vaccine.

CONCLUSION

Most physicians have good knowledge. Less than one-fourth commonly discussed sexual health with their clients. More than one-third were not interested in recommending the human papilloma virus vaccine. This issue might affect the human papilloma virus vaccination program implementation if not well addressed.

Evaluating the cost-effectiveness of HPV vaccination for adolescent girls in Japan: A comparison of 2-valent, 4-valent, and 9-valent HPV vaccines with consideration of cross-protection

OBJECTIVE

In April 2023, the Japanese Health Ministry panel approved the inclusion of the 9-valent human papillomavirus (9vHPV) vaccine in the National Immunization Program, alongside the 2-valent (2vHPV) and 4-valent HPV (4vHPV) vaccines. In response to this, we evaluated the cost-effectiveness of these three vaccines for routine immunization of girls aged 12-16 in Japan, considering the cross-protection of 2vHPV and 4vHPV vaccines.

METHODS

We constructed an age-structured mathematical model for HPV transmission, aiming to quantify the economic and epidemiological effects of various HPV vaccination strategies over a 70-year period in Japan. We determined incremental costs and quality-adjusted life years (QALYs) for each strategy, applying a 3% annual discount. Univariate and probabilistic sensitivity analyses were conducted to assess the uncertainty of our model results, with all evaluations done in 2023.

RESULTS

Our projections indicate that the HPV vaccination program in Japan will significantly reduce the incidence of HPV-related diseases. All HPV vaccination strategies, using the 2vHPV, 4vHPV, and 9vHPV vaccines, were found to be cost-effective compared to no vaccination, with incremental cost-effectiveness ratios of ¥971,447/QALY, ¥1,237,297/QALY, and ¥742,084/QALY, respectively. Direct comparisons between vaccines demonstrated that the 9vHPV vaccination was more cost-effective than the 2vHPV vaccination, whereas 4vHPV vaccination was dominated by 2vHPV vaccination.

CONCLUSIONS

Our study validates the cost-effectiveness of implementing the 9vHPV vaccine as the primary option over the 2vHPV or 4vHPV vaccine for girls in Japan. These findings underscore the need to improve the acceptance rate and coverage of HPV vaccinations in the country.

Effects of 2 and 3 Vaccinations With the Bivalent Human Papillomavirus (HPV) Vaccine on the Prevalence and Load of HPV in Clearing and Persistent Infections in Young Women

BACKGROUND

Human papillomavirus (HPV) viral load (VL) is associated with persistence, which increases cervical cancer risk. The bivalent vaccine protects against oncogenic HPV-16/18 and cross-protects against several nonvaccine types. We examined the effect of 2-dose (2D) and 3-dose (3D) vaccination on HPV prevalence and VL in clearing infections and persistent infections, 6 years and 12 years postvaccination, respectively.

METHODS

Vaginal swabs collected from the "HPV Amongst Vaccinated and Non-vaccinated Adolescents" study (HAVANA, 3D-eligible) and HAVANA-2 (2D-eligble) participants were genotyped for HPV with the SPF10-DEIA-LiPA25 system. HPV VL was measured with type-specific quantitative polymerase chain reaction (qPCR).

RESULTS

HPV-16, -18, -31, -33, and -45 clearing and/or persistent infection prevalence and HPV-16, -18, and -31 VLs in clearing infections were significantly reduced in 3D-vaccinated women compared to unvaccinated women. Except for HPV-11 and -59 clearing infections, no significant VL differences were observed among vaccinated women, ≤6 and >6 years post-vaccination. Infection numbers were low in 2D-eligible women, with no HPV-16/18 in vaccinated women. No VL differences for the remaining types were found.

CONCLUSIONS

3D vaccination reduces HPV prevalence in clearing infections and persistent infections and decreases HPV VLs in clearing infections, 12 years post-vaccination for vaccine and several nonvaccine types. 2D-eligible women had low infection numbers, with no HPV-16/18 among vaccinated women.

Early effect of bivalent human papillomavirus vaccination on cytology outcomes in cervical samples among young women in the Netherlands

BACKGROUND

The first HPV-vaccine eligible cohorts in the Netherlands will enter the cervical screening program in 2023. However, a substantial number of young women already have had a cervical sample taken before entry into the regular screening program. This study was initiated to explore early effects of HPV vaccination on detection of cytological abnormalities in cervical samples of women younger than the screening age.

METHODS

Results of cervical samples were obtained from the Dutch National Pathology Databank (PALGA) and were linked to the women's HPV vaccination status from the national vaccination registry (Praeventis) (N = 42,171). Occurrence of low-grade and high-grade squamous intraepithelial lesions or worse (LSIL and HSIL+) and high-risk HPV positive tests (hrHPV) in the first cervical sample were compared between vaccinated and unvaccinated women by multivariable logistic regression analysis, corrected for age at cervical sampling and age of vaccination (12/13 years, ≥ = 14 years).

RESULTS

For fully vaccinated women (three- or two-dose schedule), statistically significant reductions were seen for all outcomes compared to unvaccinated women (hrHPV: adjusted OR, 0.70, 95% CI, 0.63-0.79; LSIL: 0.70, 0.61-0.80; HSIL+: 0.39, 0.30-0.51).

CONCLUSIONS

By linking nation-wide registries on pathology and vaccination, we show significant beneficial early effects of HPV-vaccination on LSIL, HSIL+, CIN3/AIS/carcinoma and hrHPV detection in young women upto 24 years of age who have a cervical sample taken before entry into the cervical cancer screening program.

High vaccine effectiveness persists for ten years after HPV16/18 vaccination among young Dutch women

The current study describes the long-term effectiveness of three-dose HPV16/18 vaccination among Dutch women who were eligible for vaccination during a catch-up campaign and were followed in an observational cohort study. Ten years post vaccination, vaccine effectiveness (VE) was estimated using generalized estimating equation models. VE against persistent infections with vaccine type infections (HPV16/18) was high at 95.8%. For cross protective type persistent infections (HPV31/33/45) this was 64.6%. There were no indications of waning of protection over time. This indicates solid long-term protection is provided by the vaccine and is promising with regard to the future clinical impact.

Identification of the Human Papillomavirus Genotypes, According to the Human Immunodeficiency Virus Status in a Cohort of Women from Maputo, Mozambique

BACKGROUND

Human papillomavirus (HPV) infection is now a well-established cause of cervical cancer and other anogenital cancers. An association between human immunodeficiency virus (HIV) infection and higher HPV incidence and prevalence are commonly reported. This study was conducted to demonstrate HPV prevalence, genotypes and its characteristics, according to the HIV status in women from Maputo in Mozambique.

METHODS

A total of 233 participants with ages ranging from fourteen to forty-five were included. Cervical samples were collected, DNA extracted, and HPV genotyping was performed using the HPV Direct Flow CHIP Kit.

RESULTS

In total, 177 HIV-negative and 56 HIV-positive women were included in the analysis. The overall HPV prevalence was 63% and was significantly higher among HIV-positive women (79% versus 58% among HIV-negative women; p = 0.005). The prevalence of multiple HPV type infections was 32%. High-risk HPV types 52, 68, 35, 18 and 16 were the most frequent. A higher proportion of HIV-positive women had multiple HPV types compared with HIV-negative women.

CONCLUSIONS

This study demonstrated a high prevalence of HPV in the study cohort. HIV-positive women were identified as having the highest HPV prevalence and infection with multiple HPV types across all ages. High-risk genotypes were the most commonly found.

Human Papillomavirus Vaccine Efficacy and Effectiveness against Cancer

Human papillomavirus (HPV) is the most common sexually transmitted infection, with 15 HPV types related to cervical, anal, oropharyngeal, penile, vulvar, and vaginal cancers. However, cervical cancer remains one of the most common cancers in women, especially in developing countries. Three HPV vaccines have been licensed: bivalent (Cervarix, GSK, Rixensart, Belgium), quadrivalent (Merck, Sharp & Dome (Merck & Co, Whitehouse Station, NJ, USA)), and nonavalent (Merck, Sharp & Dome (Merck & Co, Whitehouse Station, NJ, USA)). The current HPV vaccine recommendations apply to 9 years old and above through the age of 26 years and adults aged 27–45 years who might be at risk of new HPV infection and benefit from vaccination. The primary target population for HPV vaccination recommended by the WHO is girls aged 9–14 years, prior to their becoming sexually active, to undergo a two-dose schedule and girls ≥ 15 years of age, to undergo a three-dose schedule. Safety data for HPV vaccines have indicated that they are safe. The most common adverse side-effect was local symptoms. HPV vaccines are highly immunogenic. The efficacy and effectiveness of vaccines has been remarkably high among young women who were HPV seronegative before vaccination. Vaccine efficacy was lower among women regardless of HPV DNA when vaccinated and among adult women. Comparisons of the efficacy of bivalent, quadrivalent, and nonavalent vaccines against HPV 16/18 showed that they are similar. However, the nonavalent vaccine can provide additional protection against HPV 31/33/45/52/58. In a real-world setting, the notable decrease of HPV 6/11/16/18 among vaccinated women compared with unvaccinated women shows the vaccine to be highly effective. Moreover, the direct effect of the nonavalent vaccine with the cross-protection of bivalent and quadrivalent vaccines results in the reduction of HPV 6/11/16/18/31/33/45/52/58. HPV vaccination has been shown to provide herd protection as well. Two-dose HPV vaccine schedules showed no difference in seroconversion from three-dose schedules. However, the use of a single-dose HPV vaccination schedule remains controversial. For males, the quadrivalent HPV vaccine possibly reduces the incidence of external genital lesions and persistent infection with HPV 6/11/16/18. Evidence regarding the efficacy and risk of HPV vaccination and HIV infection remains limited. HPV vaccination has been shown to be highly effective against oral HPV type 16/18 infection, with a significant percentage of participants developing IgG antibodies in the oral fluid post vaccination. However, the vaccines’ effectiveness in reducing the incidence of and mortality rates from HPV-related head and neck cancers should be observed in the long term. In anal infections and anal intraepithelial neoplasia, the vaccines demonstrate high efficacy. While HPV vaccines are very effective, screening for related cancers, as per guidelines, is still recommended.

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.

Effectiveness of various human papillomavirus vaccination strategies: A community randomized trial in Finland

INTRODUCTION

We conducted a community-randomized trial (NCTBLINDED) in Finland to assess gender-neutral and girls-only vaccination strategies with the AS04-adjuvanted human papillomavirus (HPV)-16/18 (AS04-HPV-16/18)vaccine.

METHODS

Girls and boys (12-15 years) were invited. We randomized 33 communities (1:1:1 ratio): Arm A: 90% of randomly selected girls and boys received AS04-HPV-16/18 vaccine and 10% received hepatitis B vaccine (HBV); Arm B: 90% of randomly selected girls received AS04-HPV-16/18 vaccine, 10% of girls received HBV, and all boys received HBV; Arm C: all participants received HBV. Effectiveness measurements against prevalence of HPV-16/18 cervical infection were estimated in girls at 18.5 years. The main measures were: (1) overall effectiveness comparing Arms A or B, regardless of vaccination status, vs Arm C; (2) total effectiveness comparing AS04-HPV-16/18 vaccinated girls in pooled Arms A/B vs Arm C; (3) indirect effectiveness (herd effect) comparing girls receiving HBV or unvaccinated in Arm A vs Arm C. Co-primary objectives were overall effectiveness following gender-neutral or girls-only vaccination.

RESULTS

Of 80,272 adolescents invited, 34,412 were enrolled. Overall effectiveness was 23.8% (95% confidence interval: -19.0, 51.1; P = 0.232) with gender-neutral vaccination. Following girls-only vaccination, overall effectiveness was 49.6% (20.1, 68.2; P = 0.004). Total effectiveness was over 90% regardless of vaccination strategy. No herd effect was found. Immunogenicity of the AS04-HPV-16/18 vaccine was high in both sexes.

CONCLUSIONS

This study illustrates the difficulty in conducting community randomized trials. It is not plausible that vaccinating boys would reduce overall effectiveness, and the apparent lack of herd effect was unexpected given findings from other studies. This analysis was likely confounded by several factors but confirms the vaccine's high total effectiveness as in clinical trials.

Partial Protective Effect of Bivalent Human Papillomavirus 16/18 Vaccination Against Anogenital Warts in a Large Cohort of Dutch Primary Care Patients

Background

There is ongoing debate about the possible protective effect of the bivalent human papillomavirus (2vHPV) vaccine, targeting oncogenic types HPV-16/18, against anogenital warts (AGWs), commonly attributed to HPV-6/11. We performed a retrospective registry-based open cohort study to assess the effect of 2vHPV vaccination on AGWs.

Methods

We linked general practice (ie, primary care) data from women born between 1993 and 2002, who had been eligible for HPV vaccination in the Netherlands, to the Dutch national immunization registry on an individual level. Women were followed until their first AGW diagnosis or end of follow-up. Adjusted incidence rate ratios (aIRRs) were estimated using Poisson regression with vaccination status as a time-dependent exposure.

Results

We linked data of 96 468 women with a total of 328 019 years observation time and 613 AGW diagnoses (incidence: 1.87/1000 person-years). At the end of follow-up, 61% were 2vHPV vaccinated (≥ 1 dose) of whom 91% were fully vaccinated. The AGW incidence was lower among those with ≥ 1 dose vs 0 doses (aIRR, 0.75 [95% confidence interval {CI}, .64–.88]). The effect of vaccination was stronger after full vaccination (aIRR, 0.72 [95% CI, .61–.86]) and for women who were offered vaccination at 12–13 years of age (aIRR, 0.69 [95% CI, .51–.93]) vs those at 13–16 years of age (aIRR, 0.77 [95% CI, .64–.93]).

Conclusions

This is the largest population-based study so far to examine the effect of 2vHPV vaccination on AGWs, with reliable individual information on AGW diagnoses and vaccination status. The results indicate that 2vHPV vaccination partially protects against AGWs, especially when administered in early adolescence.

Vaccine effectiveness following routine immunization with bivalent HPV vaccine: Protection against incident genital HPV infections from a reduced-dosing schedule

Background

In the Netherlands, the bivalent human papillomavirus (HPV) vaccine has been offered to preadolescent girls via the National Immunization Program in a 2-dose schedule since 2014. The current study estimates vaccine effectiveness (VE) against HPV infections up to 4 years postvaccination among girls eligible for routine 2-dose immunization.

Methods

A cohort study (HAVANA2) was used in which participants annually filled out an online questionnaire and provided a vaginal self-sample for determination of HPV by the SPF10-LiPA25 assay, able to detect 25 HPV types. VE against incident type-specific infections and pooled outcomes was estimated by a Cox proportional hazards model with shared frailty between the HPV types.

Results

In total, 2027 girls were included in the study, 1098 (54.2%) of whom were vaccinated with 2 doses. Highest incidence rate was 5.0/1000 person-years (HPV-51) among vaccinated participants and 9.1/1000 person-years (HPV-74) among unvaccinated participants. Adjusted pooled VE was 84.0% (95% confidence interval [CI], 27.0%–96.5%) against incident HPV-16/18 infections and 86.5% (95% CI, 39.5%–97.08%) against cross-protective types HPV-31/33/45.

Conclusions

Four years postvaccination, 2 doses of bivalent HPV vaccine were effective in the prevention of incident HPV-16/18 infections and provided cross-protection to HPV-31/33/45. Our VE estimates rival those from 3-dose schedules, indicating comparable protection by 2-dose schedules.

Population Impact of Girls-Only Human Papillomavirus 16/18 Vaccination in The Netherlands: Cross-Protective and Second-Order Herd Effects

Background

Human papillomavirus (HPV) vaccination programs achieve substantial population-level impact, with effects extending beyond protection of vaccinated individuals. We assessed trends in HPV prevalence up to 8 years postvaccination among men and women in the Netherlands, where bivalent HPV vaccination, targeting HPV types 16/18, has been offered to (pre)adolescent girls since 2009 with moderate vaccination coverage.

Methods

We used data from the PASSYON study, a survey initiated in 2009 (prevaccination) and repeated biennially among 16- to 24-year-old visitors of sexual health centers. We studied genital HPV positivity from 2009 to 2017 among women, heterosexual men, and unvaccinated women using Poisson generalized estimating equation models, adjusted for individual- and population-level confounders. Trends were studied for 25 HPV types detected by the SPF10-LiPA25 platform.

Results

A total of 6354 women (64.7% self-reported unvaccinated) and 2414 heterosexual men were included. Percentual declines in vaccine types HPV-16/18 were observed for all women (12.6% per year [95% confidence interval {CI}, 10.6–14.5]), heterosexual men (13.0% per year [95% CI, 8.3–17.5]), and unvaccinated women (5.4% per year [95% CI, 2.9–7.8]). We observed significant declines in HPV-31 (all women and heterosexual men), HPV-45 (all women), and in all high-risk HPV types pooled (all women and heterosexual men). Significant increases were observed for HPV-56 (all women) and HPV-52 (unvaccinated women).

Conclusions

Our results provide evidence for first-order herd effects among heterosexual men against HPV-16/18 and cross-protective types. Additionally, we show second-order herd effects against vaccine types among unvaccinated women. These results are promising regarding population-level and clinical impact of girls-only bivalent HPV vaccination in a country with moderate vaccine uptake.

Systematic literature review of cross-protective effect of HPV vaccines based on data from randomized clinical trials and real-world evidence

BACKGROUND

The extent of cross-protection provided by currently licensed bivalent and quadrivalent HPV vaccines versus direct protection against HPV 31-, 33-, 45-, 52-, and 58-related disease is debated. A systematic literature review was conducted to establish the duration and magnitude of cross-protection in interventional and observational studies.

METHODS

PubMed and Embase databases were searched to identify randomized controlled trials (RCT) and observational studies published between 2008 and 2019 reporting on efficacy and effectiveness of HPV vaccines in women against non-vaccine types 31, 33, 45, 52, 58, and 6 and 11 (non-bivalent types). Key outcomes of interest were vaccine efficacy against 6- and 12-month persistent infection or genital lesions, and type-specific genital HPV prevalence or incidence. RCT data were analyzed for the according-to-protocol (bivalent vaccine) or negative-for-14-HPV-types (quadrivalent vaccine) efficacy cohorts.

RESULTS

Data from 23 RCTs and 33 observational studies evaluating cross-protection were extracted. RCTs assessed cross-protection in post-hoc analyses of small size subgroups. Among fully vaccinated, baseline HPV-naïve women, the bivalent vaccine showed statistically significant cross-protective efficacy, although with wide confidence intervals, against 6-month and 12-month persistent cervical infections and CIN2+ only consistently for HPV 31 and 45, with the highest effect observed for HPV 31 (range 64.6% [95% CI: 27.6 to 83.9] to 79.1% [97.7% CI: 27.6 to 95.9] for 6-month persistent infection; maximal follow-up 4.7 years). No cross-protection was shown in extended follow-up. The quadrivalent vaccine efficacy reached statistical significance for HPV 31 (46.2% [15.3-66.4]; follow-up: 3.6 years). Similarly, observational studies found consistently significant effectiveness only against HPV 31 and 45 with both vaccines.

CONCLUSIONS

RCTs and observational studies show that cross-protection is inconsistent across non-vaccine HPV types and is largely driven by HPV 31 and 45. Furthermore, existing data suggest that it wanes over time; its long-term durability has not been established.

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.

Bivalent Vaccine Effectiveness Against Anal Human Papillomavirus Positivity Among Female Sexually Transmitted Infection Clinic Visitors in the Netherlands

Human papillomavirus (HPV) vaccines are indicated for anal cancer prevention, but evidence for vaccine effectiveness (VE) against anal HPV infections among women is limited. We estimated the VE (≥1 dose) against anal HPV positivity of the bivalent vaccine, whose target types HPV-16/18 are associated with approximately 90% of HPV-related anal cancers. Among 548 female STI clinic visitors 16-24 years old who provided an anal swab sample as part of a repeated cross-sectional survey, VE against HPV-16/18 was 89.9% (95% confidence interval, 63.0%-97.2%). Type-specific VE correlated well with VE against cervicovaginal HPV (Spearman ρ = 0.76), suggesting comparable effectiveness of HPV-16/18 vaccination against genital and anal infections.

Universal Human Papillomavirus Vaccination and its Impact on the Southern Italian Region

HPV is still the most common sexually transmitted infection, leading to the onset of many disorders while causing an increase in direct and indirect health costs. High Risk (HR) HPV is the primary cause of invasive cervical cancer and contributes significantly to the development of anogenital and oropharyngeal cancers. The introduction of universal HPV vaccination has led to a significant reduction in vaccine-targeted HPV infections, cross-protective genotypes, precancerous lesions and anogenital warts. Despite the several limitations of HPV vaccination programs, including vaccine type specificity, different schedules, target age-groups and poor communication, the impact has become increasingly evident, especially in countries with high vaccine uptake. We carried out a review of the most recent literature to evaluate the effects of HPV vaccination on vaccinetargeted HPV genotypes and to assess the level of cross-protection provided against non-vaccine HPV types. Subsequently, to assess the rates of HPV infection in a southeast Italian region, we performed an epidemiological investigation on the impact of vaccination on genotypes and on the prevalence and distribution of HPV infection during the twelve-year period 2006-2017 in the Local Health Unit (LHU) of Lecce. The vaccination coverage of about 70% among girls in the LHU led to an initial reduction in vaccine-targeted HPV types and cross-protective genotypes. However, the results on this population should be interpreted cautiously because the period since the start of vaccination is too short and the coverage rate is not yet optimal to evaluate the efficacy of vaccination in lowering the prevalence of non-vaccine HR HPV types in the vaccinated cohort and in older subjects. Nevertheless, it is expected that direct effects will increase further and that herd immunity will begin to emerge as vaccination coverage increases.

Sustained Cross-reactive Antibody Responses After Human Papillomavirus Vaccinations: Up to 12 Years Follow-up in the Finnish Maternity Cohort

BACKGROUND

Human papillomaviruses (HPV) cause several human cancers. Bivalent (Cervarix) and quadrivalent (qGardasil) HPV vaccines both contain virus-like particles of the major oncogenic HPV types 16 and 18, but also cross-protect against some nonvaccine types. However, data on long-term sustainability of the cross-reactive antibody responses to HPV vaccines are scarce.

METHODS

Serum samples donated 7-12 years after immunization at age 16-17 years with bivalent (n = 730) or quadrivalent (n = 337) HPV vaccine were retrieved from the population-based Finnish Maternity Cohort biobank. Serum antibody levels against HPV types 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, and 73 were determined using multiplex pseudovirion binding assay. Antibody avidity was assessed using ammonium thiocyanate treatment.

RESULTS

Seropositivity for HPV31, 33, 35, 45, 51, 52, 58, 59, 68, and 73 was increasingly common (P ≤ .001; χ 2 test for trend for each of these types) when women had high anti-HPV16 antibody levels. For 8 nonvaccine HPV types seropositivity was more common among recipients of bivalent than quadrivalent vaccine, in particular for HPV31, 35, 45, 51, 52, and 58 (P < .001). Antibody avidity was higher in the quadrivalent vaccine recipients for HPV6, 11, and two of the nonvaccine types, but lower for HPV16 and 18 (P < .001).

CONCLUSIONS

Both vaccines elicit cross-reactive antibodies detectable even 12 years after vaccination. Cross-reactive seropositivity is more common in women with high anti-HPV16 antibody response and in the bivalent vaccine recipients.

Durability of Cross-Protection by Different Schedules of the Bivalent HPV Vaccine: The CVT Trial

BACKGROUND

The Costa Rica HPV Vaccine Trial has documented cross-protection of the bivalent HPV vaccine against HPV31/33/45 up to 7 years after vaccination, even with one dose of the vaccine. However, the durability of such protection remains unknown. Here, we evaluate the efficacy of different schedules of the vaccine against HPV31/33/45 out to 11 years postvaccination, expanding to other nontargeted HPV types.

METHODS

We compared the rates of HPV infection in vaccinated women with the rates in a comparable cohort of unvaccinated women. We estimated the average vaccine efficacy (VEavg) against incident infections and tested for a change in VE over time.

RESULTS

Among 3-dose women, we observed statistically significant cross-protection against HPV31/33/45 (VEavg = 64.4%, 95% confidence interval [CI] = 57.7% to 70.0%). Additionally, we observed borderline, statistically significant cross-protection against HPV35 (VEavg = 23.2%, 95% CI = 0.3% to 40.8%) and HPV58 (VEavg = 21.2%, 95% CI = 4.2% to 35.3%). There was no decrease in VE over time (two-sided Ptrend > .05 for HPV31, -33, -35, -45, and -58). As a benchmark, VEavg against HPV16/18 was 82.0% (95% CI = 77.3% to 85.7%). Among 1-dose women, we observed comparable efficacy against HPV31/33/45 (VEavg = 54.4%, 95% CI = 21.0% to 73.7%). Acquisition of nonprotected HPV types was similar between vaccinated and unvaccinated women, indicating that the difference in HPV infection rates was not attributable to differential genital HPV exposure.

CONCLUSIONS

Substantial cross-protection afforded by the bivalent vaccine against HPV31/33/45, and to a lesser extent, HPV35 and HPV58, was sustained and remained stable after 11 years postvaccination, reinforcing the notion that the bivalent vaccine is an effective option for protection against HPV-associated cancers.

Human Papillomavirus (HPV) Vaccine Effectiveness and Potential Herd Immunity for Reducing Oncogenic Oropharyngeal HPV-16 Prevalence in the United Kingdom: A Cross-sectional Study

Background

Oropharyngeal cancer incidence is rapidly rising due to human papillomavirus (HPV) type 16 infection. The dearth of data on effectiveness of national female-only vaccination programs in preventing oral HPV infection and potential herd immunity in unvaccinated males has resulted in considerable controversy regarding the need to vaccinate males, especially in countries with high female vaccination coverage.

Methods

Subjects aged 0–65 years undergoing tonsillectomy for nonmalignant indications were recruited in 6 hospitals in the United Kingdom. Oral samples were collected as follows: oral rinse, tongue base, and pharyngeal wall brushes, then tonsil tissue (tonsillectomy). Vaccination data were obtained from regional health authorities. All samples were centrally tested for HPV DNA by polymerase chain reaction.

Results

Of 940 subjects, 243 females and 69 males were aged 12–24 years (median age, 18.6 years), with 189 (78%) females and no males vaccinated against HPV. Overall, oropharyngeal HPV-16 prevalence was significantly lower in vaccinated versus unvaccinated females (0.5% vs 5.6%, P = .04). In contrast, prevalence of any oropharyngeal HPV type was similar in vaccinated and unvaccinated females (19% vs 20%, P = .76). Oropharyngeal HPV-16 prevalence in unvaccinated males was similar to vaccinated females (0% vs 0.5%, P > .99), and lower than unvaccinated females (0% vs 5.6%, P = .08).

Conclusions

Our findings indicate that the UK female-only vaccination program is associated with significant reductions in oropharyngeal HPV-16 infections. These are also the first data to suggest potential herd immunity from female-only vaccination against oropharyngeal HPV infection in contemporaneously aged males.

Choosing the optimal HPV vaccine: The health impact and economic value of the nonavalent and bivalent HPV vaccines in 48 Gavi-eligible countries

The human papillomavirus (HPV) vaccines may provide some level of cross-protection against high-risk HPV genotypes not directly targeted by the vaccines. We evaluated the long-term health and economic impacts of routine HPV vaccination using either the nonavalent HPV vaccine or the bivalent HPV vaccine in the context of 48 Gavi-eligible countries. We used a multi-modeling approach to compare the bivalent with or without cross-protection and the nonavalent HPV vaccine. The optimal, that is, most cost-effective, vaccine was the vaccine with an incremental cost-effectiveness ratio below the per-capita gross domestic product (GDP) for each country. By 2100 and assuming 70% HPV vaccination coverage, a bivalent vaccine without cross-protection, a bivalent vaccine with favorable cross-protection and the nonavalent vaccine were projected to avert 14.9, 17.2 and 18.5 million cumulative cases of cervical cancer across all 48 Gavi-eligible countries, respectively. The relative value of the bivalent vaccine compared to the nonavalent vaccine increased assuming a bivalent vaccine conferred high cross-protection. For example, assuming a cost-effectiveness threshold of per-capita GDP, the nonavalent vaccine was optimal in 83% (n = 40) of countries if the bivalent vaccine did not confer cross-protection; however, the proportion of countries decreased to 63% (n = 30) if the bivalent vaccine conferred high cross-protection. For lower cost-effectiveness thresholds, the bivalent vaccine was optimal in a greater proportion of countries, under both cross-protection assumptions. Although the nonavalent vaccine is projected to avert more cases of cervical cancer, the bivalent vaccine with favorable cross-protection can prevent a considerable number of cases and would be considered a high-value vaccine for many Gavi-eligible countries.

Efficacy of the AS04-Adjuvanted HPV16/18 Vaccine: Pooled Analysis of the Costa Rica Vaccine and PATRICIA Randomized Controlled Trials

BACKGROUND

The AS04-adjuvanted HPV16/18 (AS04-HPV16/18) vaccine provides excellent protection against targeted human papillomavirus (HPV) types and a variable degree of cross-protection against others, including types 6/11/31/33/45. High efficacy against any cervical intraepithelial neoplasia grade 3 or greater (CIN3+; >90%) suggests that lower levels of protection may exist for a wide range of oncogenic HPV types, which is difficult to quantify in individual trials. Pooling individual-level data from two randomized controlled trials, we aimed to evaluate AS04-HPV16/18 vaccine efficacy against incident HPV infections and cervical abnormalities .

METHODS

Data were available from the Costa Rica Vaccine Trial (NCT00128661) and Papilloma Trial Against Cancer in Young Adults trial (NCT00122681), two large-scale, double-blind randomized controlled trials of the AS04-HPV16/18 vaccine. Primary analyses focused on disease-free women with no detectable cervicovaginal HPV at baseline.

RESULTS

A total of 12 550 women were included in our primary analyses (HPV arm = 6271, control arm = 6279). Incidence of 6-month persistent oncogenic and nononcogenic infections, excluding known and accepted protected types 6/11/16/18/31/33/45 (focusing on 34/35/39/40/42/43/44/51/52/53/54/56/58/59/66/68/73/70/74), was statistically significantly lower in the HPV arm than in the control arm (efficacy = 9.9%, 95% confidence interval [CI] = 1.7% to 17.4%). Statistically significant efficacy (P < .05) was observed for individual oncogenic types 16/18/31/33/45/52 and nononcogenic types 6/11/53/74. Efficacy against cervical abnormalities (all types) increased with severity, ranging from 27.7% (95% CI = 21.7% to 33.3%) to 58.7% (95% CI = 34.1% to 74.7%) for cytologic outcomes (low-grade squamous intraepithelial neoplasia lesion or greater, and high-grade squamous intraepithelial neoplasia lesion or greater, respectively) and 66.0% (95% CI = 54.4% to 74.9%) to 87.8% (95% CI = 71.1% to 95.7%) for histologic outcomes (CIN2+ and CIN3+, respectively). Comparing Costa Rica Vaccine Trial and Papilloma Trial Against Cancer in Young Adults results, there was no evidence of heterogeneity, except for type 51 (efficacy = -28.6% and 20.7%, respectively; two-sided P = .03).

CONCLUSIONS

The AS04-HPV16/18 vaccine provides some additional cross-protection beyond established protected types, which partially explains the high efficacy against CIN3+.

Measuring vaccine effectiveness against persistent HPV infections: a comparison of different statistical approaches

BACKGROUND

Persistent high-risk human papillomavirus (HPV) infection is endorsed by the World Health Organization as an intermediate endpoint for evaluating HPV vaccine effectiveness/efficacy. There are different approaches to estimate the vaccine effectiveness/efficacy against persistent HPV infections.

METHODS

We performed a systematic literature search in Pubmed to identify statistical approaches that have been used to estimate the vaccine effectiveness/efficacy against persistent HPV infections. We applied these methods to data of a longitudinal observational study to assess their performance and compare the obtained vaccine effectiveness (VE) estimates.

RESULTS

Our literature search identified four approaches: the conditional exact test for comparing two independent Poisson rates using a binomial distribution, Generalized Estimating Equations for Poisson regression, Prentice Williams and Peterson total time (PWP-TT) and Cox proportional hazards regression. These approaches differ regarding underlying assumptions and provide different effect measures. However, they provided similar effectiveness estimates against HPV16/18 and HPV31/33/45 persistent infections in a cohort of young women eligible for routine HPV vaccination (range VE 93.7-95.1% and 60.4-67.7%, respectively) and seemed robust to violations of underlying assumptions.

CONCLUSIONS

As the rate of subsequent infections increased in our observational cohort, we recommend PWP-TT as the optimal approach to estimate the vaccine effectiveness against persistent HPV infections in young women. Confirmation of our findings should be undertaken by applying these methods after longer follow-up in our study, as well as in different populations.

Vaccinating for Whom? Distinguishing between Self-Protective, Paternalistic, Altruistic and Indirect Vaccination

Preventive vaccination can protect not just vaccinated individuals, but also others, which is often a central point in discussions about vaccination. To date, there has been no systematic study of self- and other-directed motives behind vaccination. This article has two major goals: first, to examine and distinguish between self- and other-directed motives behind vaccination, especially with regard to vaccinating for the sake of third parties, and second, to explore some ways in which this approach can help to clarify and guide vaccination debates and policy. I propose conceiving of vaccination in terms of three basic elements: the vaccination decision-maker, the vaccine recipient and the primary beneficiary. I develop a taxonomy based on the relations between these elements to distinguish four kinds of vaccination: self-protective, paternalistic, altruistic and indirect. I finally discuss the case of human papillomavirus vaccine regulation for men and women to show how each kind of vaccination is associated with and raises specific ethical questions.

Bivalent Human Papillomavirus (HPV) Vaccine Effectiveness Correlates With Phylogenetic Distance From HPV Vaccine Types 16 and 18

To substantiate cross-protection reported across AS04-adjuvanted bivalent human papillomavirus (HPV) vaccine (2vHPV) studies, we reevaluated vaccine effectiveness against type-specific HPV positivity as a function of phylogenetic distance to vaccine target types HPV-16 and -18. We provide evidence of sustained cross-protection up to 8 years postvaccination in a high-risk population in the Netherlands. Moreover, our findings suggest that genomic distance better explains cross-protection than distance measures based on capsid antigens only. Taken together, 2vHPV is predicted to provide partial cross-protection against HPV-31, -33, -35, -45, -52, and possibly -58, that is, acknowledged oncogenic types with close phylogenetic relationships to HPV-16 or -18.

Multi-Infection Patterns and Co-infection Preference of 27 Human Papillomavirus Types Among 137,943 Gynecological Outpatients Across China

Background: The epidemiological feature of human papillomavirus (HPV) infection is distinctive in China. We aimed to investigate the multi-infection patterns and co-infection preference of 27 HPV types among gynecological outpatients across China.

Methods: Overall 137,943 gynecological outpatients were recruited from eight tertiary hospitals located in seven regions of China, between July 1st, 2014 and December 31st, 2016. The overall, region-specific, age-specific and type-specific prevalence of HPV infection were calculated, respectively. The pattern of HPV infection was also evaluated. Furthermore, rate ratio was calculated to evaluate the co-infection preference of any two HPV genotypes.

Results: The overall prevalence of 27 HPVs' [17 high-risk (hr)/10 low-risk (lr)] infection was 23.5%. The age-specific HPV prevalence showed a “U-shaped” pattern. The most prevalent hrHPV genotypes were 16, 52, and 58. Multiple infections were detected in 25.8% of the HPV-positive women, in which dual infection was more prevalent. HPV 16/18 were likely to co-infected with HPV 31 but unlikely with HPV 52/58, i.e., the co-infection of HPV 16 with HPV 31 was high (3.5-fold), but low for HPV 58 (1.8-fold), and 52 (1.2-fold), while the co-infection of HPV 18 with HPV 31 was high (4.3-fold), but low for HPV 52 (1.9-fold), and 58 (1.7-fold).

Conclusions: We found age-specific prevalence of HPV infection showed a “U-shaped” pattern for high and low risk HPV, suggesting the importance of screening among younger women and the necessary of detection among older women. We found a novel co-infection preference of HPV 16/18 with 31, 52, and 58, suggesting a need of developing and marketing prophylactic HPV vaccines that protect against more genotypes in China.

Peak neutralizing and cross-neutralizing antibody levels to human papillomavirus types 6/16/18/31/33/45/52/58 induced by bivalent and quadrivalent HPV vaccines

We performed an independent comparison of neutralizing and cross-neutralizing antibody (ab) levels seven months after initiation of three-dose, six-month vaccination schedules with the bivalent and quadrivalent human papillomavirus (HPV) vaccines in adolescent Finnish and Indian females, respectively. We used a semi-automated Pseudovirion-Based Neutralization Assay and observed significantly higher HPV16/18 peak ab-levels in bivalent as compared to quadrivalent vaccine recipients. Bivalent vaccine induced cross-neutralizing HPV31/33/45/52/58 antibodies significantly more frequently and to higher levels than the quadrivalent vaccine. The correlation of bivalent vaccine-induced HPV45 ab-levels with HPV16/18 ab-levels was stronger than that of corresponding quadrivalent vaccine-induced ab-levels, suggesting a qualitatively different cross-reactive response. Our findings on the comparison of the immunogenicity of two HPV vaccine tested in two different populations indicate that further head-to-head studies are warranted.

Persisting Antibody Response 9 Years After Bivalent Human Papillomavirus (HPV) Vaccination in a Cohort of Dutch Women: Immune Response and the Relation to Genital HPV Infections

The bivalent human papillomavirus (HPV) vaccine is highly effective and induces robust serological responses. Using a Dutch prospective cohort initiated in 2009, including 744 vaccinated and 294 unvaccinated girls (1993–1994) who provide a vaginal self-swab sample, serum sample, and questionnaire yearly, we report a high, persisting antibody response up to 9 years after vaccination for vaccine types HPV-16 or HPV-18. Antibodies against nonvaccine HPV types 31, 33, 45, 52, and 58 were lower but still significantly higher than in unvaccinated individuals. This was also reflected in the seroprevalence. We compared participant characteristics and antibody levels between vaccinated women with and those without HPV infections 1 year before infection (204 incident and 64 persistent infections), but we observed no consistent difference in type-specific antibody levels. Having a high-risk HPV infection was associated with sexual risk behavior and smoking 1 year before infection. Although high antibody levels are necessary for protection, our study suggests that on the individual level other factors such as HPV exposure or antibody avidity could be important.

Estimating incidence rates of grouped HPV types: A systematic review and comparison of the impact of different epidemiological assumptions

BACKGROUND

Some studies on human papillomavirus (HPV) provide not only type-specific incidence rates (IR), but also IRs of HPV groupings (e.g. the nonavalent grouping). We made an inventory of the different approaches used to calculate such IRs and assessed their impact on the estimated IRs of HPV groupings.

METHODS

We performed a systematic review assessing all approaches used in literature to estimate IRs. Subsequently we applied these approaches to data of a Dutch cohort study on HPV in men who have sex with men (H2M). IRs were estimated for six different HPV groupings.

RESULTS

The systematic review yielded six different approaches (A-F) for estimating the IRs, varying in exclusion criteria at baseline, and the definitions of an incident event and person-time. Applying these approaches to the H2M dataset (n = 749), we found differences in the number of participants at risk, number of incidents events, person-time, and IR. For example, for the nonavalent grouping, depending on the approach chosen, the IR varied between 3.09 and 6.54 per 100 person-months.

CONCLUSION

In published studies different epidemiological assumptions are used to estimate IRs of grouped HPV types, leading to widely differing estimates of IRs. IRs between different studies may therefore not be comparable.

Selective Persistence of HPV Cross-Neutralising Antibodies following Reduced-Dose HPV Vaccine Schedules

The duration of cross-neutralising antibody responses (cross-NAb) following HPV immunisation is unknown. We compared cross-NAb responses in cohort of girls who were either unimmunised or had received immunisation with one, two or three doses of 4vHPV (Gardasil^®, Merck Inc., Kenilworth, NJ, USA) six years earlier, before and one month after a booster dose of 2vHPV (Cervarix^®, GSK, Brentford, UK). NAb to potentially cross-reactive HPV genotypes 31, 33, 45, 52 and 58 were measured using a HPV pseudovirion-based neutralisation assay. Girls who had previously received at least one dose of 4vHPV had significantly higher NAb titres for HPV31 when compared with unimmunised girls, whereas no difference in NAb titre was observed for four other genotypes (33, 45, 52 and 58). Following a single further immunisation with 2vHPV, NAb titres to each of the five tested HPV genotypes were comparable for girls who previously received one, two or three doses of 4vHPV, and were significantly higher than for previously unimmunised girls. Immunisation with one, two or three doses of 4vHPV induced NAb to HPV31 that persisted for six years, but there was no persistence of NAb to HPV33, 45, 52 or 58. Our results suggest that one or two doses of 4vHPV may provide long-term protection against HPV31.

Long-term Cross-reactivity Against Nonvaccine Human Papillomavirus Types 31 and 45 After 2- or 3-Dose Schedules of the AS04-Adjuvanted Human HPV-16/18 Vaccine

This analysis focused on long-term cross-reactive immunogenicity against nonvaccine human papillomavirus (HPV) types 31 and 45 following 2 doses of AS04-adjuvanted HPV-16/18 vaccine in girls aged 9-14 years or following 3 doses in women aged 15-25 years, for up to 3 years (HPV-070 study) and up to 5 years (HPV-048 study) after the first vaccination. Both schedules elicited antibodies against HPV-31 and HPV-45 up to 5 years after first dose. The antibody concentration was similar in young girls as compared to women. Specific CD4+ T-cell and B-cell responses to HPV-31 and HPV-45 at month 36 were similar across groups. Clinical trials registration: NCT01381575 and NCT00541970.

Prevalence of cervical disease at age 20 after immunisation with bivalent HPV vaccine at age 12-13 in Scotland: retrospective population study

OBJECTIVE

To quantify the effect on cervical disease at age 20 years of immunisation with bivalent human papillomavirus (HPV) vaccine at age 12-13 years.

DESIGN

Retrospective population study, 1988-96.

SETTING

National vaccination and cervical screening programmes in Scotland.

PARTICIPANTS

138 692 women born between 1 January 1988 and 5 June 1996 and who had a smear test result recorded at age 20.

MAIN OUTCOME MEASURES

Effect of vaccination on cytology results and associated histological diagnoses from first year of screening (while aged 20), calculated using logistic regression.

RESULTS

138 692 records were retrieved. Compared with unvaccinated women born in 1988, vaccinated women born in 1995 and 1996 showed an 89% reduction (95% confidence interval 81% to 94%) in prevalent cervical intraepithelial neoplasia (CIN) grade 3 or worse (from 0.59% (0.48% to 0.71%) to 0.06% (0.04% to 0.11%)), an 88% reduction (83% to 92%) in CIN grade 2 or worse (from 1.44% (1.28% to 1.63%) to 0.17% (0.12% to 0.24%)), and a 79% reduction (69% to 86%) in CIN grade 1 (from 0.69% (0.58% to 0.63%) to 0.15% (0.10% to 0.21%)). Younger age at immunisation was associated with increasing vaccine effectiveness: 86% (75% to 92%) for CIN grade 3 or worse for women vaccinated at age 12-13 compared with 51% (28% to 66%) for women vaccinated at age 17. Evidence of herd protection against high grade cervical disease was found in unvaccinated girls in the 1995 and 1996 cohorts.

CONCLUSIONS

Routine vaccination of girls aged 12-13 years with the bivalent HPV vaccine in Scotland has led to a dramatic reduction in preinvasive cervical disease. Evidence of clinically relevant herd protection is apparent in unvaccinated women. These data are consistent with the reduced prevalence of high risk HPV in Scotland. The bivalent vaccine is confirmed as being highly effective vaccine and should greatly reduce the incidence of cervical cancer. The findings will need to be considered by cervical cancer prevention programmes worldwide.

Effect of the bivalent HPV vaccine on viral load of vaccine and non-vaccine HPV types in incident clearing and persistent infections in young Dutch females

Background

HPV vaccination with the bivalent vaccine is efficacious against HPV16 and 18 infections and cross-protection against non-vaccine HPV types has been demonstrated. Here, we assessed (cross-) protective effects of the bivalent HPV16/18 vaccine on incident and persistent infections and viral load (VL) of fifteen HPV types in an observational cohort study monitoring HPV vaccine effects.

Methods

Vaginal samples were obtained annually. Type-specific VL assays were developed for HPV6,11,31 33,35,39,45,51,52,56,58,59 and 66 and used in addition to existing HPV16 and 18 assays. Rate differences of incident clearing and persistent infections were correlated with differences in VL and vaccination status.

Results

HPV16/18 vaccination resulted in significantly lower incidence of HPV16/18 infections and significantly lower VL in breakthrough HPV16 (p<0.01) and 18 infections (p<0.01). The effects of vaccination on non-vaccine type VL were ambiguous. Incidence and/or persistence rates of HPV31, 33, 35 and 45 were reduced in the vaccinated group. However, no significant type specific VL effects were found against HPV31, 33, 45, 52 in the vaccinated group. For HPV 6, 59 and 66 no significant reductions in numbers of incident and persistent infections were found, however borderline) VL reductions following vaccination were observed for HPV6 (p = 0.01), 59 (p = 0.10) and 66 (p = 0.03), suggesting a minor effect of the vaccine on the VL level of these HPV types. Overall, vaccination resulted in infections with slightly lower VL, irrespective of HPV type.

Conclusions

In conclusion, vaccination with the bivalent HPV16/18 vaccine results in significantly reduced numbers of HPV16 and 18 incidence rates and reduced VL in breakthrough infections. Significant reductions in incident and/or persistent HPV31, 33, 35 and 45 infections were found, but no significant effect was observed on the VL for infections with these types. For the other non-vaccine HPV types no reduction in incident and/or persistent infections were found, but overall the VL tended to be somewhat lower in vaccinated women.

Post-hoc analysis from phase III trials of human papillomavirus vaccines: considerations on impact on non-vaccine types

BACKGROUND

Substantial heterogeneity has been reported in efficacy against high-grade cervical intraepithelial neoplasia (CIN) irrespective of HPV type in phase III results for bivalent and quadrivalent human papillomavirus virus (HPV) vaccines (AS04-HPV and qHPV). Real-world data recently confirmed a very high overall impact of AS04-HPV, supporting the validity of the observed heterogeneity. To explore the reasons for heterogeneous efficacy, we assessed vaccine impact on high-grade lesions not caused by vaccine types.

RESEARCH METHODS

We extracted case counts of CIN lesions containing (1) at least one vaccine HPV type, (2) at least one vaccine HPV type and a high-risk non-vaccine type (co-infections) and (3) no vaccine types (non-vaccine or no high-risk HPV types). Based on these, Phase III cross-protective efficacies were estimated with exclusion (3) and with inclusion (2 and 3) of co-infections.

RESULTS

Cross-protective efficacy of AS04-HPV against CIN3 lesions ranges from 81.3% (95%CI: 34.7;96.5) (excluding co-infections) to 88.5% (95%CI:62.4;97.8) (including co-infections). For qHPV the efficacy ranges from -58.7% (95%CI: -180.5;8.5) (excluding co-infections) to 13.1% (95%CI: -39.0;45.9) (including co-infections).

CONCLUSIONS

Heterogenous overall efficacy against CIN3 between AS04-HPV and qHPV is driven by differential efficacy against lesions that do not contain vaccine types, which may be related to the impact of different adjuvants on the immune response.

Assessment of herd effects among women and heterosexual men after girls-only HPV16/18 vaccination in the Netherlands: A repeated cross-sectional study

Data on the impact of human papillomavirus (HPV) vaccination on the population HPV prevalence are largely obtained from women. We assessed the impact of the girls‐only HPV16/18 vaccination program in the Netherlands that started in 2009, on trends in HPV prevalence among women and heterosexual men, using data from the PASSYON study. In this cross‐sectional study, the HPV prevalence among 16‐ to 24‐year‐old visitors to sexually transmitted infection clinics was assessed in 2009, 2011, 2013, and 2015. We compared the genital postvaccination HPV prevalence with the prevaccination prevalence (2009) using Poisson GEE models. In total, we included 4,996 women and 1,901 heterosexual men. The percentage of women who reported to be vaccinated increased from 2.3% in 2009 to 37% in 2015. Among all women, the HPV16/18 prevalence decreased from 23% prevaccination to 15% in 2015 (adjusted prevalence ratio [aPR] 0.62, p_trend < 0.01). Among heterosexual men, the HPV16/18 prevalence decreased from 17% prevaccination to 11% in 2015 (aPR 0.52, p_trend < 0.01). Of the heterosexual men with a steady partner, HPV16/18 prevalence was lower among those whose steady partner had been vaccine‐eligible in the national immunization program (aPR 0.13). Among unvaccinated women, the HPV16/18 prevalence in 2015 was not different from prevaccination. The decreasing HPV16/18 prevalence among heterosexual men and the reduced HPV16/18 prevalence among heterosexual men with a vaccine‐eligible steady partner strongly suggests herd protection from girls‐only vaccination. Absence of notable herd effects among unvaccinated women 6 years postvaccination may be due to the moderate vaccine uptake among girls in the Netherlands.

What's new?

Human papillomavirus (HPV) is a sexually transmitted virus that plays a causal role in the development of anogenital and oropharyngeal cancers in both men and women. The population‐level impact of HPV vaccination programs on the HPV prevalence has however mainly been studied in women. This study shows decreasing trends in the HPV16 and HPV18 prevalence among both women and heterosexual men after the introduction of a girls‐only HPV16/18 vaccination program in the Netherlands. The findings provide compelling evidence for herd protection in men. Because HPV16/18 are the most oncogenic types, HPV‐related cancers are expected to decline in both sexes after girls‐only HPV vaccination.

Ten years of HPV vaccination in the Netherlands: current evidence and future challenges in HPV-related disease prevention

INTRODUCTION

Girls-only vaccination against human papillomavirus (HPV) type 16 and 18 was implemented in the Netherlands in 2009. Despite the evidence of the efficacy against precancerous lesions, cross-protection induced by the vaccine and a greater potential for cancer prevention than cervical cancer only, vaccine coverage in the girls-only program has remained below target levels.

AREAS COVERED

In this paper, we review the literature from the Netherlands on the effectiveness and cost-effectiveness of HPV vaccination since vaccine introduction, give an account of the coverage, safety and effectiveness of HPV vaccination as has been reported in the Dutch surveillance program and discuss challenges of the current HPV vaccination program.

EXPERT COMMENTARY

Girls-only HPV vaccination may confer a substantial health gain in HPV-related disease prevention. However, vaccine coverage declined remarkably recently possibly related to safety concerns, limiting the benefits from girls' vaccination and increasing the potential additional benefit of sex-neutral HPV vaccination. Considering the emergence of novel vaccination and screening options and the change from cytology- to HPV-based screening in 2017, further research is required to inform decisions on the optimization of an integrated vaccination and screening program.

Substantial Decline in Prevalence of Vaccine-Type and Nonvaccine-Type Human Papillomavirus (HPV) in Vaccinated and Unvaccinated Girls 5 Years After Implementing HPV Vaccine in Norway

Background

In 2009, quadrivalent human papillomavirus (HPV) vaccine was introduced in a school-based single-cohort program targeting 12-year-old girls in Norway. We estimated the impact of the Norwegian HPV immunization program.

Methods

Three birth cohorts of 17-year-old girls, 2 nonvaccine-eligible cohorts (born 1994 or 1996) and 1 vaccine-eligible cohort (born 1997) were invited to deliver urine samples. The samples were analyzed for 37 HPV genotypes. HPV prevalence was compared between birth cohorts and between vaccinated and unvaccinated girls within and across birth cohorts after linkage to the Norwegian Immunisation Registry.

Results

In total, 17749 urine samples were analyzed. A 42% (95% confidence interval [CI], 37%-47%) reduction in any HPV type and 81% (95% CI, 76%-85%) reduction in vaccine types (HPV-6/11/16/18) were observed in the vaccine-eligible cohort compared to the 1994 cohort. Vaccine types were reduced by 54% (95% CI, 39%-66%) and 90% (95% CI, 86%-92%) in unvaccinated and vaccinated girls, respectively, from the 1997 cohort, compared with unvaccinated girls born in 1994. A significant reduction was also observed for several nonvaccine types. Vaccine-type prevalence was reduced by 77% (95% CI, 65%-85%) in vaccinated compared with unvaccinated girls from the 1997 cohort.

Conclusions

In this largely HPV-naive population, we observed a substantial reduction in vaccine and nonvaccine types in vaccinated and unvaccinated girls following introduction of HPV vaccination.