Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: case-control study nested within a population based screening programme in Australia

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.

HPV prevalence and genotype distribution among 38 056 women in Weifang, China: a cross-sectional study

OBJECTIVES

Human papillomavirus (HPV) infection is closely associated with cervical cancer, especially the persistent infection of high-risk HPV (HR-HPV) genotypes. Therefore, investigating the HPV prevalence, age-specific, genotype distribution and the impact of the COVID-19 pandemic among large populations was essential for HPV screening and optimising vaccination.

DESIGN

This was a cross-sectional study.

METHODS

A total of 38 056 cervical epithelial cell specimens were collected in Weifang city from January 2018 to December 2022. The study was divided into seven age groups based on the age of the participants. HPV genotype testing was performed by using a commercial kit which is designed for the detection of 23 HPV genotypes.

RESULT

A total of 8998 women were infected with HPV, with an overall positive rate of 23.64% (8998/38 056). Single infection of HPV was dominant among different age groups, which accounted for 71.33% of total infections. The most prevalent genotype was HR-HPV 16 (4.33%), followed by 52, 58, 53 and 68. Low-risk HPV (LR-HPV) 42 exhibited the highest prevalence (2.19%) among six LR-HPV genotypes, representing a novel finding. There was a significant difference in the prevalence across different age groups (p<0.01), with the highest prevalence in the group under 25 years old. During the 3 year COVID-19 breakout period, the number of HPV samples received in 2020, 2021 and 2022 was reduced by 24.03%, 14.79% and 24.76%, respectively. In 2018-2022, the annual prevalence varied between 21.09% and 25.30%, with a decreasing trend, while the prevalence of HR-HPV 39, 56, 31 and LR-HPV 42 increased.

CONCLUSION

This study indicates a high-HPV infection rate and age-specific distribution characteristics of HPV genotype infections, as well as analyses of the impact of the COVID-19 outbreak on the HPV prevalence, which provides an epidemiological basis for the control and prevention of HPV infection in this region.

Barriers to undergoing cervical cancer screening among health sciences university students in Japan: A cross-sectional study

In most developed countries, cervical cancer screening and human papillomavirus vaccination have reduced cervical cancer incidence. However, the incidence has been increasing in Japan, possibly because of the low screening rate. Although cervical cancer incidence has increased in people in their 20s, the screening rate among 20-24-year-olds in Japan is only 10.2%, meaning that cervical cancer screening rates should be increased among young Japanese women. We conducted a questionnaire survey among students at health sciences universities to determine their knowledge of cervical cancer, screening rates, and barriers to screening. Students taking specialized medical courses were highly knowledgeable; recognition of the facts that "cervical cancer can be prevented through screening" and that "the risk of cervical cancer increases in one's 20s" was significantly high among those who underwent screening. On the other hand, only 7.5% of students used the free coupons provided for screening. Knowledge of cervical cancer improves screening rates. Therefore, educational programs to raise awareness of the importance of cervical cancer screening among non-medical and health sciences university students and young women in general are required.

Human papillomavirus vaccine effectiveness by age at vaccination: A systematic review

Human papillomavirus (HPV) vaccines work by preventing infections prior to natural exposure. Thus, it is likely more effective at younger ages, and it is important to understand how effectiveness might be diminished when administered at older ages. We conducted a systematic review of HPV vaccine effectiveness studies published between 2007 and 2022 that included an analysis of effectiveness against vaccine-type HPV infections, anogenital warts, cervical abnormalities and cervical cancer by age at vaccine initiation or completion. Searching multiple databases, 21 studies were included and results were summarized descriptively. Seventeen studies found the highest vaccine effectiveness in the youngest age group. Vaccine effectiveness estimates for younger adolescents ages 9-14 years ranged from approximately 74% to 93% and from 12% to 90% for adolescents ages 15-18 years. These results demonstrate that the HPV vaccine is most effective against HPV-related disease outcomes when given at younger ages, emphasizing the importance of on-time vaccination.

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.

The Clinical and Economic Impact of a Nonavalent Versus Bivalent Human Papillomavirus National Vaccination Program in Taiwan

OBJECTIVES

This study aimed to estimate the epidemiologic and economic impact of a nonavalent human papillomavirus (HPV) vaccination program for 13- to 14-year-old females compared with that of the bivalent vaccine in Taiwan.

METHODS

A previously developed dynamic transmission model for the nonavalent HPV vaccine was adapted to the Taiwan setting. The natural history of cervical cancer and genital warts was simulated by the HPV model assuming an 80% vaccination coverage rate in girls aged 13 to 14 years of age with a 2-dose schedule for the nonavalent and bivalent HPV vaccines. A lifetime duration of vaccine protection was assumed for the HPV vaccine types.

RESULTS

The model estimated that the nonavalent HPV vaccine would prevent an additional 15 951 cervical cancer cases, 6600 cervical cancer-related deaths, 176 702 grade 2 or grade 3 cervical intraepithelial neoplasia cases, 103 959 grade 1 cervical intraepithelial neoplasia cases, and 1 115 317 genital warts cases compared with the bivalent HPV vaccine. The nonavalent HPV vaccination program was projected to cost an additional New Taiwan dollars (NTD) 675.21 per person and to produce an additional 0.00271 quality-adjusted life-year per person over 100 years compared with the bivalent HPV vaccine. Thus, the incremental cost-effectiveness ratio of the nonavalent HPV vaccine versus the bivalent HPV vaccine was NTD 249 462/quality-adjusted life-year.

CONCLUSIONS

A nonavalent HPV vaccination program for 13- to 14-year-old girls would have additional public health and economic impacts and would be highly cost-effective compared with the bivalent HPV vaccine, relative to per capita gross domestic product, which is estimated at NTD 746 526 for Taiwan.

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.

Long-term human papillomavirus vaccination effectiveness and immunity in Rwandan women living with and without HIV: a study protocol

INTRODUCTION

Prophylactic human papillomavirus (HPV) vaccines have been shown to be highly effective in protecting women against cervical infections, high-grade abnormalities and cancer caused by the targeted HPV types. However, the evidence for their effectiveness in women living with HIV (WLWH) is less clear.

METHODS

WLWH and HIV-negative women who likely did (birth cohorts 1996 and later) and WLWH and HIV(-) negative who likely did not (birth cohorts before 1996) receive HPV vaccination (n=3028; 757 participants for each of the four groups). Between groups, we will compare cervicovaginal, anal and oral prevalent and 6-12 month persistent HPV6/11/16/18 infections as measured using a modified AmpFire HPV genotyping assay that tests for 15 high-risk or intermediate-risk HPV genotypes, HPV6 and HPV11. We will also compare the HPV immune response in HPV-vaccinated WLWH to HPV-vaccinated HIV-negative women using an anti-HPV16 and anti-HPV18 ELISA. Vaccination status will be confirmed through national vaccination records.

ANALYSIS

We will calculate point prevalence and prevalence of 6-12 month persisting infections by individual HPV-type specific infections and groups of infections for each anatomic site and for each group of women. Results will be stratified by age at vaccination, age at enrolment and the number of doses (3 vs 2) as well as other factors possibly associated with HPV prevalence. Differences in endpoints between groups, overall and between subgroups, will be tested for statistical significance (p<0.05) using Fisher's exact or Pearson χ² test. Differences in geometric mean titres and seropositivity will be tested for statistical significance using the Mann-Whitney and Fisher's exact tests, respectively.

ETHICS AND DISSEMINATION

The study was approved by the Albert Einstein College of Medicine Institutional Review Board and the Rwanda National Ethics Committee. Results will be disseminated through publication in peer-reviewed journals.

Motivators and Barriers to HPV Vaccination: A Qualitative Study of Underserved Women Attending Planned Parenthood

Human papilloma virus (HPV) is the most common sexually transmitted infection in the United States. Disease-associated strains of HPV can cause genital warts and six cancer types. HPV-associated cervical cancer disproportionately impacts medically underserved women including Black and Latina women with respect to incidence, prevalence, and mortality rates. Although safe and effective vaccines are available, HPV vaccination rates remain low among low-income individuals and women of color. The current study examined individual and structural motivators and barriers to HPV vaccination among medically underserved women utilizing a Planned Parenthood health center in Southeast Pennsylvania. Guided by narrative engagement theory (NET), qualitative interviews (N = 24) were used to elicit HPV vaccine decision stories from both vaccinated and unvaccinated women. Using a phronetic iterative data analysis approach, we identified three motivators to vaccinate against HPV: (1) receiving an explicit vaccine recommendation from a healthcare provider (a structural determinant), (2) feeling empowered to take control of one’s health (an individual determinant), and (3) knowing someone infected with HPV (an individual determinant). Among unvaccinated participants, barriers to HPV vaccination included: (1) not receiving an explicit vaccine recommendation from a healthcare provider (a structural determinant), (2) low perceived risk for acquiring HPV or that HPV is not severe (an individual determinant), and (3) lack of maternal support to vaccinate (a structural determinant). Healthcare providers are optimally positioned to fill the gap in prior missed vaccine opportunities and empower women by recommending HPV vaccination.

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.

Impact of catch-up human papillomavirus vaccination on cervical conization rate in a real-life population in France

Objective

To evaluate the impact of catch-up human papillomavirus (HPV) vaccination on conization rates in France in a large population-based study.

Methods

We conducted a retrospective real-life cohort study on data collected prospectively by French National Health Insurance. Echantillon généralistes des bénéficiaires (EGB) is a database composed of demographic and health care utilization data for a 1/97^th sample of the French population. We extracted data about all women born between 1983 and 1991, corresponding to the catch-up population (vaccination after 14 years old) at the time of implementation of HPV vaccination. The primary outcome was the occurrence of conization (all types of procedures) compared between vaccinated and non-vaccinated women.

Results

The cohort consisted of 42,452 women. Vaccination coverage (at least one dose) was low (9.8%, n = 4,129), but increased with time from vaccine implementation, from 0% in the 1983 cohort to 31% in the 1991 cohort. The conization rate was 1% for the overall population. The risk of conization for women between the ages of 19 and 30 years was reduced in the vaccinated group with a Hazard Ratio (HR) of 0.59 (95% CI[0.39–0.90]; p = 0.043).

Conclusions

With a 10-year follow-up, catch-up HPV vaccination is associated with risk reduction of conization between the ages of 19 and 30.

Multicancer early detection test: Preclinical, translational, and clinical evidence-generation plan and provocative questions

Minimally invasive molecular biomarkers have been applied to the early detection of multiple cancers in large scale case-control and cohort studies. These demonstrations of feasibility herald the potential for permanent transformation of current cancer screening paradigms. This commentary discusses the major opportunities and challenges facing the preclinical development and clinical validation of multicancer early detection test strategies. From a diverse set of early detection research perspectives, the authors recommend specific approaches and highlight important questions for future investigation.

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.

Real-world impact and effectiveness assessment of the quadrivalent HPV vaccine: a systematic review of study designs and data sources

INTRODUCTION

Vaccine effectiveness and impact studies are typically observational, generating evidence after vaccine launch in a real-world setting. For human papillomavirus (HPV) vaccination studies, the variety of data sources and methods used is pronounced. Careful selection of study design, data capture and analytical methods can mitigate potential bias in such studies.

AREAS COVERED

We systematically reviewed the different study designs, methods, and data sources in published evidence (1/2007-3/2020), which assessed the quadrivalent HPV vaccine effectiveness and impact on cervical/cervicovaginal, anal, and oral HPV infections, anogenital warts, lesions in anus, cervix, oropharynx, penis, vagina or vulva, and recurrent respiratory papillomatosis.

EXPERT OPINION

The rapid growth in access to real-world data allows global monitoring of effects of different public health interventions, including HPV vaccination programs. But the use of data which are not collected or organized to support research also underscore a need to develop robust methodology that provides insight of vaccine effects and consequences of different health policy decisions. To achieve the WHO elimination goal, we foresee a growing need to evaluate HPV vaccination programs globally. A critical appraisal summary of methodology used will provide timely guidance to researchers who want to initiate research activities in various settings.

Cervical cancer prevention and control in women living with human immunodeficiency virus

Despite being highly preventable, cervical cancer is the fourth most common cancer and cause of cancer death in women globally. In low-income countries, cervical cancer is often the leading cause of cancer-related morbidity and mortality. Women living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome are at a particularly high risk of cervical cancer because of an impaired immune response to human papillomavirus, the obligate cause of virtually all cervical cancers. Globally, approximately 1 in 20 cervical cancers is attributable to HIV; in sub-Saharan Africa, approximately 1 in 5 cervical cancers is due to HIV. Here, the authors provide a critical appraisal of the evidence to date on the impact of HIV disease on cervical cancer risk, describe key methodologic issues, and frame the key outstanding research questions, especially as they apply to ongoing global efforts for prevention and control of cervical cancer. Expanded efforts to integrate HIV care with cervical cancer prevention and control, and vice versa, could assist the global effort to eliminate cervical cancer as a public health problem.

Data Linkage in Australia: The First 50 Years

Population-based data linkage has a long history in Australia from its beginnings in Western Australia in the 1970s to the coordinated national data linkage infrastructure that exists today. This article describes the journey from an idea to a national data linkage network which has impacts on the health and well-being of Australians from preventing developmental anomalies to responding to the COVID-19 pandemic. Many enthusiastic and dedicated people have contributed to Australia's data linkage capability over the last 50 years. They have managed to overcome a number of challenges including gaining stakeholder and community support; navigating complex legal and ethical environments; establishing cross-jurisdictional collaborations, and gaining ongoing financial support. The future is bright for linked data in Australia as the infrastructure built over the last 50 years provides a firm foundation for further expansion and development, ensuring that Australia's linked health and human services data continues to be available to address the evolving challenges of the next half century.

Prevalence, characteristics, and distribution of HPV genotypes in women from Zhejiang Province, 2016-2020

Objective

To evaluate and understand the prevalence of HPV genotypes and characteristics of female populations in specific areas and the relationship with cervical lesions, which can effectively guide cervical cancer screening and formulate HPV vaccine prevention strategies.

Methods

A total of 77,443 women who visited gynecological clinics and underwent health examinations in the Second Affiliated Hospital of Zhejiang University School of Medicine during 2016–2020 were enrolled in this survey. Cervical samples were collected for HPV DNA genotyping and cervical cytology testing. Cervical biopsies were performed for patients with visible cervical abnormality or abnormal cytological results.

Results

The results showed the 5-year overall positive rate was 22.3%, of which the gynecology clinic group had significantly more positive results compared with the health examination group (P < 0.001). The five most common genotypes in Zhejiang Province were HPV 52, 58, CP8304, 16, and 51 (23.9%, 12.7%, 11.7%, 11.7% and 9.3%). HPV infection was age-specific, with the highest infection rate in the age group ≤ 20 compared to other age groups (P < 0.001). HPV infection was also season-specific, with the highest infection rate in spring or winter. The main HPV infection mode was single infection (P = 0.004), but patients ≤ 20 years old were more likely to develop multiple infections (51.0%). HPV 16, 52 and 58 were the main genotypes that caused cytological abnormalities and HPV16, 18, 56, 58 and 66 were independent risk factors for cervical lesions (OR = 2.352, 1.567, 2.000, 1.694, 1.889; all P < 0.05). Further analysis found HPV 16 and 18 were the main genotypes that cause cervical cancer histological abnormalities and were independent risk factors for cervical cancer (OR = 5.647, P < 0.001; OR = 3.495, P = 0.036).

Conclusion

This article analyzed the prevalence of distribution characteristics of HPV infection and revealed the corelation between HPV infection and cytological and histological abnormalities. Comprehensive results of this survey will help Zhejiang Province to formulate public health policies and provide evidence for future selection of specific HPV vaccines.

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.

Effectiveness of the CoronaVac vaccine in older adults during a gamma variant associated epidemic of covid-19 in Brazil: test negative case-control study

OBJECTIVE

To estimate the effectiveness of the inactivated whole virus vaccine, CoronaVac (Sinovac Biotech), against symptomatic covid-19 in the elderly population of São Paulo state, Brazil during widespread circulation of the gamma variant.

DESIGN

Test negative case-control study.

SETTING

Community testing for covid-19 in São Paulo state, Brazil.

PARTICIPANTS

43 774 adults aged ≥70 years who were residents of São Paulo state and underwent reverse transcription polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 from 17 January to 29 April 2021. 26 433 cases with symptomatic covid-19 and 17 622 test negative controls with covid-19 symptoms were formed into 13 283 matched sets, one case with to up to five controls, according to age, sex, self-reported race, municipality of residence, previous covid-19 status, and date of RT-PCR test (±3 days).

INTERVENTION

Vaccination with a two dose regimen of CoronaVac.

MAIN OUTCOME MEASURES

RT-PCR confirmed symptomatic covid-19 and associated hospital admissions and deaths.

RESULTS

Adjusted vaccine effectiveness against symptomatic covid-19 was 24.7% (95% confidence interval 14.7% to 33.4%) at 0-13 days and 46.8% (38.7% to 53.8%) at ≥14 days after the second dose. Adjusted vaccine effectiveness against hospital admissions was 55.5% (46.5% to 62.9%) and against deaths was 61.2% (48.9% to 70.5%) at ≥14 days after the second dose. Vaccine effectiveness ≥14 days after the second dose was highest for the youngest age group (70-74 years)-59.0% (43.7% to 70.2%) against symptomatic disease, 77.6% (62.5% to 86.7%) against hospital admissions, and 83.9% (59.2% to 93.7%) against deaths-and declined with increasing age.

CONCLUSIONS

Vaccination with CoronaVac was associated with a reduction in symptomatic covid-19, hospital admissions, and deaths in adults aged ≥70 years in a setting with extensive transmission of the gamma variant. Vaccine protection was, however, low until completion of the two dose regimen, and vaccine effectiveness was observe to decline with increasing age among this elderly population.

Importance of Lifetime Sexual History on the Prevalence of Genital Human Papillomavirus (HPV) Among Unvaccinated Adults in the National Health and Nutrition Examination Surveys: Implications for Adult HPV Vaccination

BACKGROUND

Although the United States Food and Drug Administration recently approved the human papillomavirus (HPV) vaccine for individuals aged 27-45 years, the Centers for Disease Control and Prevention did not change its guidelines for routine HPV vaccination. Since recommendations for adult vaccination emphasize shared clinical decision-making based on risk of new infections, we examined the relationship between HPV prevalence and sexual behavior.

METHODS

This study was conducted among 5093 HPV-unvaccinated, sexually experienced adults aged 18-59 years in the National Health and Nutrition Examination Surveys (2013-2016). For each sex and age group, adjusted prevalences of 9-valent vaccine-specific, high-risk, and any HPV infection were estimated by number of lifetime sexual partners (LTSPs) using logistic regression. An analysis restricted to persons who did not have a new sexual partner in the past year (ie, removing those at highest risk of newly acquired HPV) was also conducted.

RESULTS

In each age group, genital HPV prevalence was higher among persons with >5 LTSPs compared with 1-5 LTSPs in both males and females. There were only slight reductions in HPV prevalence after removing participants who reported a new sexual partner in the past year. For example, among females aged 27-45 years with >5 LTSPs, the adjusted prevalence of 9-valent vaccine-type HPV infection was 13.4% (95% confidence interval [CI], 9.9%-17.0%) in the full population compared to 12.1% (95% CI, 8.8%-15.4%) among those with no new sexual partners.

CONCLUSIONS

Prevalent HPV infection was primarily reflective of cumulative exposures over time (higher LTSPs). New exposures had limited impact, emphasizing the need to consider sexual history in the decision-making process for adult HPV vaccination.

Postpartum HPV Vaccination Rate and Differences in Background Characteristics Between HPV Vaccinated and Unvaccinated Postpartum Women: Strict Monitoring and Follow-Up of Postpartum HPV Vaccination Program

There is a need to increase the vaccine completion rates in women who have already received human papillomavirus (HPV) vaccines. With vaccines requiring multiple doses, designing a vaccination control program and increasing the proportion of women who complete vaccination are critical and remain as huge challenges. Currently, there are no published reports on the differences in the background characteristics between postpartum women who are vaccinated or unvaccinated against HPV. This study aimed to determine the vaccination rates of the second and third doses of HPV vaccination utilizing an achievable HPV vaccination program in postpartum women. In this retrospective study, 243 postpartum women attending Chiayi Chang Gung Memorial Hospital between March and September 2014 were enrolled. These women were classified into two groups: one group received the HPV vaccine under a practical, controlled postpartum HPV vaccination program, and the other group did not. The rates for the second and third rounds of HPV vaccination in postpartum women were calculated. The differences in the background characteristics between the two groups were determined using the Student’s t test, chi-square test or Fisher’s exact test, and the multiple logistic models, as appropriate. Under the controlled postpartum HPV vaccination program, the completion rate for the three doses of postpartum HPV vaccination was 97.2%. Significant differences were observed according to maternal age, gender of the newborn, and postpartum Pap smear results between the two groups in our study. In conclusion, the controlled postpartum HPV vaccination program is a reasonable method for achieving an excellent completion rate for the three doses of postpartum HPV vaccination and may be a good model for any multiple-dose vaccination protocol.

Effectiveness of HPV vaccine by age at vaccination and number of doses: protocol for a population-based matched case-control study

INTRODUCTION

In 2006, the first human papillomavirus (HPV) vaccine was approved by the Food and Drug Administration in the USA based on pre-licensure clinical trials that found it to be highly efficacious at preventing persistent infection and precancerous, high-grade cervical lesions (HGCLs) caused by viral types the vaccine protects against. However, the real-world effectiveness of HPV vaccines as used in clinical practice may be quite different from the efficacy found in pre-licensure clinical trials. More than 10 years have passed since the introduction of the vaccine programme. It is critical to determine if the full benefits of HPV are being realised in real-world settings.

METHODS AND ANALYSIS

The objectives of this study were to estimate the effectiveness of HPV vaccines as used in real-world clinical settings and to determine the degree to which the vaccine's effectiveness varies based on age at the time of immunisation and the number of doses received. The study will be a population-based, matched case-control study. Cases will be women with newly diagnosed HGCL associated with HPV types 16 and 18. Matched controls will be women with a normal Pap test result, matched individually to cases in a 2:1 ratio by age, a practice and date of testing. Medical records will be reviewed to determine dates of receipt of the HPV vaccine for all participants. We will use multivariate conditional logistic regression to control for potential confounders.

ETHICS AND DISSEMINATION

This protocol presents minimal risk to the subjects. This protocol has received approval from the Institutional Review Board of Yale University (HIC: 1502015308), and a Health Insurance Portability and Accountability Act (HIPAA) Waiver of Authorisation has been granted to allow investigators to recruit subjects for the study. Findings will be disseminated through peer-reviewed, open-access scientific journals and conference presentations.

Effectiveness of human papillomavirus vaccination in young Japanese women: a retrospective multi-municipality study

In Japan, government support for human papillomavirus (HPV) vaccination began in November 2010. However, the mass media repeatedly reported on severe adverse events. The Japanese Ministry of Health, Labor and Welfare suspended proactive recommendations for HPV vaccines in June 2013. Japan's HPV vaccination rate dropped from 70% to less than 1% in 2017.We examined cervical cancer screening results in terms of abnormal cytology, histology, and HPV vaccination status among 11,903 women aged 20 to 25 y in the fiscal year 2015. The overall rate of HPV vaccination was 26.1% (3,112/11,903). Regarding cytology, the rate of atypical squamous cells of undetermined significance (ASC-US) or worse was 3.3% (103/3,112) in women who received HPV vaccination (vaccine (+) women) and 5.6% (496/8,791) in women who did not (vaccine (-) women). The rate of high-grade squamous intraepithelial lesion (HSIL) or worse was 0.26% (8/3,112) in vaccine (+) women and 0.81% (72/8,791) in vaccine (-) women. Regarding histology, the rate of cervical intraepithelial neoplasia 1 or worse (CIN1+) was 1.4% (42/3,112) in vaccine (+) women and 2.1% (178/8,791) in vaccine (-) women. The rates of CIN2+ and CIN3+ were similar regardless of vaccination. We found a significantly lower incidence of CIN in vaccine (+) women. These results suggest that the resumption of recommending HPV vaccination as primary prevention for cervical cancer is needed in Japan.

Vaccine Effectiveness Against Prevalent Anal and Oral Human Papillomavirus Infection Among Men Who Have Sex With Men-United States, 2016-2018

BACKGROUND

In the United States, human papillomavirus (HPV) vaccination has been recommended for young adult men who have sex with men (MSM) since 2011.

METHODS

The Vaccine Impact in Men study surveyed MSM and transgender women aged 18-26 years in 3 US cities during 2016-2018. Self-collected anal swab and oral rinse specimens were assessed for 37 types of HPV. We compared HPV prevalence among vaccinated and unvaccinated participants and determined adjusted prevalence ratios (aPR) and 95% confidence intervals (CI).

RESULTS

Among 1767 participants, 704 (39.8%) self-reported receiving HPV vaccine. Median age at vaccination (18.7 years) was older than age at first sex (15.7 years). Quadrivalent vaccine-type HPV was detected in anal or oral specimens from 475 (26.9%) participants. Vaccine-type HPV prevalence was lower among vaccinated (22.9%) compared with unvaccinated (31.6%) participants; aPR for those who initiated vaccination at age ≤18 years was 0.41 (CI, 0.24-0.57) and at age >18 years was 0.82 (CI, 0.67-0.98). Vaccine effectiveness of at least 1 HPV vaccine dose at age ≤18 years or >18 years was 59% and 18%, respectively.

CONCLUSIONS

Findings suggest real-world effectiveness of HPV vaccination among young adult MSM. This effect was stronger with younger age at vaccination.

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.

Newcomer knowledge, attitudes, and beliefs about human papillomavirus (HPV) vaccination

BACKGROUND

Human Papillomavirus (HPV) is the most common sexually transmitted infection in Canada and around the world. Vaccination is an effective prevention strategy, but uptake is low, especially among newcomers to Canada. We sought to understand newcomers' knowledge, attitudes, and beliefs (KAB) on HPV and HPV vaccination and their role in HPV vaccine acceptance.

METHODS

Newcomers were defined as individuals born outside Canada, (i.e., individuals born in a different country, the majority of whom are immigrants or refugees, but also includes students and undocumented migrants). Eligible participants were newcomers, aged 16 or older and who could read or write in English, French or Arabic. Surveys were administered in two community health centres in Ottawa, Canada that primarily engage with newcomer populations. Follow-up interviews were conducted either at the community health centre or over the phone, depending on participants' preferences.

RESULTS

Fifty participants completed the survey, the majority of whom were women (74%) and spoke Arabic as their first language (54%). Seven participants completed supplemental interviews to complement their survey responses. The majority (70%) of participants had not previously heard of HPV. Less than half (46%) knew that the vaccine is effective in preventing certain types of cancer; nearly 40% incorrectly believed the vaccine could cure HPV. Qualitative interviews supported the survey findings.

CONCLUSIONS

Despite a lack of HPV knowledge due to cultural and language barriers, there is still a strong desire among newcomers to receive the vaccine, especially when accompanied by a physician recommendation. Cultural and language-appropriate resources are needed to help newcomers make informed vaccination decisions and promote HPV vaccine uptake.

Human papillomavirus vaccine to prevent cervical intraepithelial neoplasia in Japan: A nationwide case-control study

Cervical cancer remains among the most common cancers in women worldwide and can be prevented by vaccination. The Ministry of Health, Labour and Welfare of Japan suspended active recommendation of regular human papillomavirus (HPV) vaccines in 2013 because of various symptoms including chronic pain and motor impairment. This nationwide case-control study from April 2013 to March 2017 targeted women aged 20-24 years old at cervical screening. We compared HPV vaccination exposure between those with abnormal and normal cytology. Abnormal cytology was classified based on the results of histological test and we calculated the odds ratio (OR) and 95% confidence interval (CI) of the above endpoints and vaccination exposure using the conditional logistic regression model and estimated vaccine effectiveness using the formula (1 - OR) × 100. A total of 2483 cases and 12 296 controls (one-to-five matching) were eligible in 31 municipalities in Japan. The distribution of histological abnormalities among cases was 797 CIN1 (including dysplasia) (32.1%), 165 CIN2 (6.7%), 44 CIN3 (1.8%), and eight squamous cell carcinoma (SCC) (0.3%). The OR of HPV vaccination compared with no vaccination for abnormal cytology, CIN1+, CIN2+, and CIN3+ versus controls was 0.42 (95% CI, 0.34-0.50), 0.42 (95% CI, 0.31-0.58), 0.25 (95% CI, 0.12-0.54), and 0.19 (95% CI, 0.03-1.15), respectively, equating to a vaccine effectiveness of 58.5%, 57.9%, 74.8%, and 80.9%, respectively. Eight patients had SCC, none was vaccinated. This nationwide case-control study in Japan demonstrated a substantial risk reduction in abnormal cytology and CIN among women who did versus those who did not receive HPV vaccination.

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.

Human Papillomavirus Antibody Levels and Quadrivalent Vaccine Clinical Effectiveness in Perinatally Human Immunodeficiency Virus-infected and Exposed, Uninfected Youth

BACKGROUND

Persons who are infected with human immunodeficiency virus (HIV) are at high risk of human papillomavirus (HPV)-associated cancers. The objectives are to compare antibody titers to HPV 6, 11, 16, and 18 and rate of abnormal cytology between perinatally HIV-infected (PHIV) and perinatally HIV-exposed, uninfected (PHEU) youth.

METHODS

This is a prospective observational cohort study of HPV4 vaccinated youth performed as part of the multicenter Pediatric HIV/AIDS Cohort Study Adolescent Master Protocol. Seroconversion and geometric mean titer (GMT) against HPV types 6, 11, 16, and 18 were calculated. Vaccine effectiveness included rates of abnormal cervical cytology and genital warts.

RESULTS

Seroconversion to HPV 6, 11, 16, and 18 occurred in 83%, 84%, 90%, and 62% of 310 vaccinated PHIV youth compared to 94%, 96%, 99%, and 87% of 148 vaccinated PHEU youth, respectively (P < .05 for all comparisons). GMTs were lower in the PHIV vs PHEU within each category of HPV4 doses received. Higher GMTs were associated with younger age, lower HIV type 1 RNA viral load, and higher CD4% at first HPV4 vaccination, as well as shorter duration between last vaccine dose and antibody specimen. Abnormal cytology occurred in 33 of 56 PHIV and 1 of 7 PHEU sexually active vaccinated females, yielding incidence rates per 100 person-years of 15.0 (10.9 to 20.6) and 2.9 (0.4 to 22.3), respectively.

CONCLUSION

Antibody titers to HPV4 were lower for all serotypes in PHIV compared to PHEU youth. Protection against abnormal cytology was also diminished in sexually active PHIV females.

Human papillomavirus vaccine effectiveness within a cervical cancer screening programme: cohort study

OBJECTIVE

To assess the effectiveness of an HPV vaccination programme in reducing the risk of cervical abnormalities identified at subsequent screening.

DESIGN

Retrospective cohort study using administrative health data.

SETTING

General population of Ferrara Province, Italy.

POPULATION

Female residents born in 1986-1993 and participating in the organized cervical screening programme in 2011-2018, who were eligible for HPV vaccination in catch-up cohorts.

METHODS

Logistic regression to evaluate the potential association between abnormal cervical cytology and one, two, three or at least one dose of HPV vaccine.

MAIN OUTCOME MEASURES

Cervical abnormalities, as predicted by low-grade or high-grade cytology, by number of vaccine doses, stratified by age.

RESULTS

The sample consisted of 7785 women (mean age 27.5 years, SD 2.3). Overall, 391 (5.0%) were vaccinated with ≥1 dose and 893 (11.5%) had abnormal cytology. Women receiving at least one vaccine dose were significantly less likely to have an abnormal cytology (adjusted odds ratio 0.52; 95% confidence interval 0.34-0.79). Similar results were observed for women receiving a single dose, for both bivalent and quadrivalent vaccines, and applying buffer periods (excluding cytological outcomes within 1 month, 6 months and 1 year of the first dose).

CONCLUSIONS

In the context of an organised cervical screening programme in Italy, catch-up HPV vaccination almost halved the risk of cytological abnormalities.

TWEETABLE ABSTRACT

Among Ferrara women, vaccination against human papillomavirus halved the risk of screening cervical abnormalities.

Human Papillomavirus Vaccines: An Updated Review

Human papillomavirus (HPV) vaccines, which were introduced in many countries in the past decade, have shown promising results in decreasing HPV infection and related diseases, such as warts and precancerous lesions. In this review, we present the updated information about current HPV vaccines, focusing on vaccine coverage and efficacy. In addition, pan-gender vaccination and current clinical trials are also discussed. Currently, more efforts should be put into increasing the vaccine’s coverage, especially in low- and middle-income countries. Provision of education on HPV and vaccination is one of the most important methods to achieve this. Vaccines that target HPV types not included in current vaccines are the next stage in vaccine development. In the future, all HPV-related cancers, such as head and neck cancer, and anal cancer, should be tracked and evaluated, especially in countries that have introduced pan-gender vaccination programs. Therapeutic vaccines, in combination with other cancer treatments, should continue to be investigated.

Human papillomavirus vaccination 2020 guideline update: American Cancer Society guideline adaptation

The American Cancer Society (ACS) presents an adaptation of the current Advisory Committee on Immunization Practices recommendations for human papillomavirus (HPV) vaccination. The ACS recommends routine HPV vaccination between ages 9 and 12 years to achieve higher on-time vaccination rates, which will lead to increased numbers of cancers prevented. Health care providers are encouraged to start offering the HPV vaccine series at age 9 or 10 years. Catch-up HPV vaccination is recommended for all persons through age 26 years who are not adequately vaccinated. Providers should inform individuals aged 22 to 26 years who have not been previously vaccinated or who have not completed the series that vaccination at older ages is less effective in lowering cancer risk. Catch-up HPV vaccination is not recommended for adults aged older than 26 years. The ACS does not endorse the 2019 Advisory Committee on Immunization Practices recommendation for shared clinical decision making for some adults aged 27 through 45 years who are not adequately vaccinated because of the low effectiveness and low cancer prevention potential of vaccination in this age group, the burden of decision making on patients and clinicians, and the lack of sufficient guidance on the selection of individuals who might benefit.

Has Human Papillomavirus (HPV) Vaccination Prevented Adverse Pregnancy Outcomes? Population-Level Analysis After 8 Years of a National HPV Vaccination Program in Australia

Background

Human papillomavirus (HPV) infection, and its sequelae of precancerous cervical lesions and their subsequent treatment, have been linked with an increased risk of adverse pregnancy outcomes. Publicly funded HPV vaccination of female adolescents began in Australia in 2007 with initial catch-up to age 26 years.

Methods

Using data from the National Perinatal Data Collection we compared rates of preterm births and small-for-gestational-age infants born in Australia 2000–2015. We used generalized linear models, assuming a Poisson distribution and log link function, with single-year categories of infant birth year, maternal age, and age-specific HPV vaccination coverage as independent variables.

Results

In maternal cohorts with 60%–80% HPV vaccination coverage as achieved in Australia, there was a relative rate reduction of 3.2% (95% confidence interval, 1.1%–5.3%) in preterm births and 9.8% (8.2% to 11.4%) in small-for-gestational-age infants, after adjustment for infant’s birth year and maternal age.

Conclusion

This analysis provides provisional population-level evidence of a reduction in adverse pregnancy outcomes in cohorts of women offered HPV vaccination. Confounding by smoking or other variables and/or ecological analysis limitations, however, cannot be excluded. These findings indicate potential broader benefits of HPV vaccination than have been documented to date.

Effectiveness of 1, 2, and 3 Doses of Human Papillomavirus Vaccine Against High-Grade Cervical Lesions Positive for Human Papillomavirus 16 or 18

Before 2016, human papillomavirus (HPV) vaccination was recommended on a 3-dose schedule. However, many vaccine-eligible US females received fewer than 3 doses, which provided an opportunity to evaluate the real-world vaccine effectiveness (VE) of 1, 2, and 3 doses. We analyzed data on cervical intraepithelial neoplasia (CIN) grades 2-3 and adenocarcinoma in situ (designated CIN2+) from the HPV Vaccine Impact Monitoring Project (HPV-IMPACT; 2008-2014). Archived tissue from CIN2+ lesions was tested for 37 types of HPV. Women were classified by number of doses received ≥24 months before CIN2+ detection. Using a test-negative design, VE was estimated as 1 minus the adjusted odds ratio from a logistic regression model that compared vaccination history for women whose lesions tested positive for HPV-16/18 (vaccine-type cases) with that for women who had all other CIN2+ lesions (controls). Among 3,300 women with available data on CIN2+, typing results, and vaccine history, 1,561 (47%) were HPV-16/18-positive, 136 (4%) received 1 dose of HPV vaccine, 108 (3%) received 2 doses, and 325 (10%) received 3 doses. Adjusted odds ratios for vaccination with 1, 2, and 3 doses were 0.53 (95% confidence interval (CI): 0.37, 0.76; VE = 47%), 0.45 (95% CI: 0.30, 0.69; VE = 55%), and 0.26 (95% CI: 0.20, 0.35; VE = 74%), respectively. We found significant VE against vaccine-type CIN2+ after 3 doses of HPV vaccine and lower but significant VE with 1 or 2 doses.

Can the prophylactic quadrivalent HPV vaccine be used as a therapeutic agent in women with CIN? A randomized trial

Background

Human papillomavirus (HPV) is one of the most significant risk factors for cervical cancer. The HPV vaccine has a very significant impact on the incidence of cervical cancer. The present study aimed to investigate the impact of prophylactic quadrivalent HPV vaccine in the treatment of women with cervical intraepithelial neoplasia (CIN 1–3).

Methods

This randomized controlled trial was conducted in the Shahid Sadoughi University of Medical Sciences (SSUMS), Yazd, Iran, from October 2011 to November 2015 in women with histologically confirmed residual/recurrent CIN 1 or high-grade CIN (CIN 2–3). Eligible women were assigned randomly to an intervention and a control group. Women in the intervention group were given HPV vaccinations while those in the control group were not. Participants were followed up for 24 months. Primary and secondary outcomes, and adverse effects of the treatment in the two groups were compared using Student’s t test, the chi-square test, or Fisher’s exact test. P values < 0.05 or less were considered statistically significant.

Results

Three-hundred and twelve women were randomized to the two groups; the data of 138 in the intervention group and 104 in the control group were analyzed. The mean age of the women was 32.59 ± 4.85 years. Differences in age, marital status, and grades of CIN weren’t significant between the two groups. At the end of the two-year follow-up period, the number of women with CIN 2–3 in the intervention and control groups was reduced by 75% (from 93 to 23) versus 40% (from 69 to 41). The efficacy of the HPV vaccine in women with CIN 1–3 was 58.7% (p = 0.018). No serious adverse effects related to the vaccines were reported.

Conclusions

The prophylactic quadrivalent HPV vaccine after treatment may have a therapeutic effect in women with residual/recurrent CIN 1 or high-grade CIN (CIN 2–3).

Trial registration

Iranian Registry of Clinical Trials, IRCT20190603043801N1. Registered 24 July 2019 – Retrospectively registered, http://www.irct.ir/user/trial/40017/view

The Use of Test-negative Controls to Monitor Vaccine Effectiveness: A Systematic Review of Methodology

BACKGROUND

The test-negative design is an increasingly popular approach for estimating vaccine effectiveness (VE) due to its efficiency. This review aims to examine published test-negative design studies of VE and to explore similarities and differences in methodological choices for different diseases and vaccines.

METHODS

We conducted a systematic search on PubMed, Web of Science, and Medline, for studies reporting the effectiveness of any vaccines using a test-negative design. We screened titles and abstracts and reviewed full texts to identify relevant articles. We created a standardized form for each included article to extract information on the pathogen of interest, vaccine(s) being evaluated, study setting, clinical case definition, choices of cases and controls, and statistical approaches used to estimate VE.

RESULTS

We identified a total of 348 articles, including studies on VE against influenza virus (n = 253), rotavirus (n = 48), pneumococcus (n = 24), and nine other pathogens. Clinical case definitions used to enroll patients were similar by pathogens of interest but the sets of symptoms that defined them varied substantially. Controls could be those testing negative for the pathogen of interest, those testing positive for nonvaccine type of the pathogen of interest, or a subset of those testing positive for alternative pathogens. Most studies controlled for age, calendar time, and comorbidities.

CONCLUSIONS

Our review highlights similarities and differences in the application of the test-negative design that deserve further examination. If vaccination reduces disease severity in breakthrough infections, particular care must be taken in interpreting vaccine effectiveness estimates from test-negative design studies.

HPV vaccines: alternative dosage schedules

Introduction: The randomized control trials (RCTs) that resulted in licensure of HPV VLP vaccines used a traditional prime, prime-boost schedule for a subunit protein vaccine. These vaccines delivered predominantly to 9-14-year-old females with this schedule have been shown to be highly effective against vaccine HPV-type disease (CIN and genital warts) and infection. A two-dose prime-boost schedule is immunologically non-inferior to 3 doses in 9-14-year-olds and is currently widely adopted. However, even with a reduced dosage schedule, these vaccines are expensive to buy and expensive and logistically complex to deliver especially in low resource countries that bear the major burden of cervical cancer the most prevalent of HPV caused cancers.Areas covered: Observational studies and post hoc analysis of RCTs show that 1 dose, although immunologically inferior to 2 and 3 doses, is as effective at preventing persistent infection with vaccine HPV types at least for 7-10 years. To address the issue of alternative dosage schedules that include 1 dose either as a single dose or extended 1 + 1 with the second dose 3-5 years post-first dose are under investigation in RCTs.Expert opinion: Since, in the short term, vaccine supplies are constrained and will impact on the ability of countries to implement HPV vaccine programs: the challenges and opportunities of the alternative approaches in this scenario are discussed.

Reduction in HPV16/18 prevalence among young women with high-grade cervical lesions following the Japanese HPV vaccination program

The Japanese government began a human papillomavirus (HPV) vaccination program for girls aged 12‐16 years in 2010 but withdrew its recommendation in 2013 because of potential adverse effects, leading to drastically reduced vaccination uptake. To evaluate population‐level effects of HPV vaccination, women younger than 40 years of age newly diagnosed with cervical intraepithelial neoplasia grade 1‐3 (CIN1‐3), adenocarcinoma in situ (AIS), or invasive cervical cancer (ICC) have been registered at 21 participating institutes each year since 2012. A total of 7709 women were registered during 2012‐2017, of which 5045 were HPV genotyped. Declining trends in prevalence of vaccine types HPV16 and HPV18 during a 6‐year period were observed in CIN1 (50.0% to 0.0%, P_trend < .0001) and CIN2‐3/AIS (83.3% to 45.0%, P_trend = .07) only among women younger than 25 years of age. Overall, HPV vaccination reduced the proportion of HPV16/18‐attributable CIN2‐3/AIS from 47.7% to 33.0% (P = .003): from 43.5% to 12.5% as routine vaccination (P = .08) and from 47.8% to 36.7% as catch‐up vaccination (P = .04). The HPV16/18 prevalence in CIN2‐3/AIS cases was significantly reduced among female individuals who received their first vaccination at age 20 years or younger (P = .02). We could not evaluate vaccination effects on ICC owing to low incidence of ICC among women aged less than 25 years. We found HPV vaccination to be effective in protecting against HPV16/18‐positive CIN/AIS in Japan; however, our data did not support catch‐up vaccination for women older than 20 years. Older adolescents who skipped routine vaccination due to the government’s suspension of its vaccine recommendation could benefit from receiving catch‐up vaccination before age 20 years.

The impact of 10 years of human papillomavirus (HPV) vaccination in Australia: what additional disease burden will a nonavalent vaccine prevent?

Background: A National human papilloma virus (HPV) Vaccination Programme for the prevention of HPV infection and associated disease using the quadrivalent HPV vaccine (4vHPV) has been funded and implemented in Australia since 2007, initially for girls only and extended to boys in 2013, with uptake rates among the highest observed worldwide. Aim: We report on the impact of this national programme on HPV prevalence and associated disease burden and estimate the potential impact of adopting a nonavalent HPV (9vHPV) vaccine. Methods: We performed a non-systematic literature review of studies measuring the burden of HPV-associated disease and infection in Australia before and after introduction of HPV vaccination. We also included key national reports with estimates of HPV-related disease burden. Results: Substantial declines in high-grade cervical disease and genital warts among vaccine-eligible women have been observed. Reductions in genital warts incidence and HPV prevalence among heterosexual men of similar age were observed before introduction of the male vaccination programme, indicating a substantial herd effect. 9vHPV vaccine is expected to prevent up to 90% of cervical and 96% of anal cancers. Of an estimated 1,544 HPV-associated cancers in 2012, 1,242 would have been preventable by the 4vHPV vaccine and an additional 187 anogenital cancers by the 9vHPV vaccine. Conclusions: Vaccination using 4vHPV vaccine has had a large demonstrable impact on HPV-related disease in Australia. A switch to 9vHPV could further reduce the HPV-associated cancer burden. With continued high coverage among both males and females, elimination of vaccine-type HPV disease seems achievable in Australia.

Very Low Prevalence of Vaccine Human Papillomavirus Types Among 18- to 35-Year Old Australian Women 9 Years Following Implementation of Vaccination

Introduction

A quadrivalent human papillomavirus vaccination program targeting females aged 12-13 years commenced in Australia in 2007, with catch-up vaccination of 14-26 year olds through 2009. We evaluated the program's impact on HPV prevalence among women aged 18-35 in 2015.

Methods

HPV prevalence among women aged 18-24 and 25-35 was compared with prevalence in these age groups in 2005-2007. For women aged 18-24, we also compared prevalence with that in a postvaccine study conducted in 2010-2012.

Results

For the 2015 sample, Vaccination Register-confirmed 3-dose coverage was 53.3% (65.0% and 40.3% aged 18-24 and 25-35, respectively). Prevalence of vaccine HPV types decreased from 22.7% (2005-2007) and 7.3% (2010-2012), to 1.5% (2015) (P trend < .001) among women aged 18-24, and from 11.8% (2005-2007) to 1.1% (2015) (P = .001) among those aged 25-35.

Conclusions

This study, reporting the longest surveillance follow-up to date, shows prevalence of vaccine-targeted HPV types has continued to decline among young women. A substantial fall also occurred in women aged 25-35, despite lower coverage. Strong herd protection and effectiveness of less than 3 vaccine doses likely contributed to these reductions.

Effectiveness of school-based and high-risk human papillomavirus vaccination programs against cervical dysplasia in Manitoba, Canada

The effectiveness of a vaccination program is influenced by its design and implementation details and by the target population characteristics. Using routinely collected population-based individual-level data, we assessed the effectiveness (against cervical dysplasia) of Manitoba's quadrivalent human papillomavirus (qHPV) routine school-based vaccination program and a short-lived campaign that targeted women at high-risk of developing cervical cancer. Females ≥9 years old who received the qHPV vaccine in Manitoba (Canada) between September 1, 2006, and March 31, 2013 (N = 31,442) were matched on age and area of residence to up to three unvaccinated females. Cox proportional hazards models were used to estimate qHPV VE against high-grade (HSILs) and low-grade squamous intraepithelial lesions (LSILs) and atypical squamous cells of undetermined significance (ASCUS). Among 14-17-year-old participants who had Pap cytology after enrollment, the adjusted qHPV VE estimates were 30% (17-58%) and 36% (21-48%) against the detection of HSILs and LSILs, respectively. There was, however, no evidence of program effectiveness among females vaccinated at ≥18 years of age and among those with a history of abnormal cytology, who were mostly vaccinated as part of the high-risk program. Estimates of VE for females vaccinated in the school-based program are consistent with the expected benefits from qHPV vaccination. No similar benefits were detected among women vaccinated at an older age, and those with abnormal cytology, who were targeted by the high-risk program. Further efforts should be targeted at achieving higher vaccine coverage among preadolescents, prior to the initiation of sexual activity.

Current issues facing the introduction of human papillomavirus vaccine in China and future prospects

The introduction of human papillomavirus (HPV) vaccination in China aims to prevent HPV infection in all women. The issues that China might face include high cost of vaccines made in other countries, shortage in HPV vaccine supply, negative events attributed to vaccination (whether justified or not) that jeopardizes the general public's confidence in the HPV vaccine, cultural and literacy barriers, and sensitivity to receiving a vaccine for a sexually transmitted disease. Ensuring the effective delivery of the HPV vaccine in China, a country with vast economic, geographical, and cultural complexities, will require a commitment of significant resources. In light of the high price of imported vaccines, the availability of locally manufactured HPV vaccines would greatly facilitate the national HPV vaccination program. New evidence supporting the efficacy of a two-dose regime in younger adolescents would also be advantageous in terms of affordability and logistical simplicity of vaccine administration. Furthermore, it would potentially enhance the compliance and uptake, especially for hard to reach women in remote regions.

[HPV: Carcinogenic implications and preventive measures]

Human oncogenic papillomaviruses (HPV) have an increasingly prominent role in the genesis of many cancers. The oncogenic mechanisms associated with HPV are now better known and make it possible to explain the etiopathogenesis of the association. HPV status is now sought for certain cancers and conditions both prognosis and management of patients. Preventive antiviral vaccination has become a real public health issue and aims to effectively reduce the prevalence of cervical, anal and oropharynx cancer, HPV-associated. However, vaccination against HPV still lags behind. The purpose of this review is to redefine the involvement of HPV in several cancers as well as current therapeutic challenges of HPV-related cancers, notably in term of prevention.

Papillomavirus and cancers: should we extend vaccination to boys in France?

Background

In 2006, the HPV (Human papillomavirus) 6/11/16/18 quadrivalent vaccine was approved by the European Medicines Agency and obtained its marketing authorization in both girls and boys. Currently, the French guidelines recommend and refund vaccination of girls aged 11 to 14 with a catch-up program for females from 15 to 19 years old.

Discussion

In France, HPV vaccination coverage tends to decrease. At the end of 2015, the vaccination coverage with three doses reached only 14% in 16-year-old girls (three doses). Although men are also affected by HPV-related diseases such as anal cancer, ano-genital warts, penile cancer or upper aerodigestive tract cancer, vaccine recommendations in France are for girls only. To face the high prevalence of anal cancer and related diseases, the best option is vaccination. Moreover, by offering men a way to prevent diseases against which they do not have any protection yet, universal vaccination could better take into account the ethical issues of prevention. In this paper, we present the point of view of different medical specialties concerning the potential benefit of extending vaccination to boys.

Conclusion

HPV vaccination of both genders could benefit from a better public acceptance and contribute to a better coverage, especially in countries with low vaccination rates.

The feasibility of universal HPV vaccination program in Shenzhen of China: a health policy analysis

Background

HPV vaccination for the prioritized adolescent girls is well accepted and implemented in developed countries as an effective measure for cervical cancer prevention and control with increasing population-level effectiveness evidence accumulated. This study is to assess the feasibility of universal HPV vaccination among adolescent girls to inform strategies to manage political dimensions of policy-making process in Shenzhen, China, offering insights for other low- and middle-income countries undergoing HPV vaccine introduction.

Methods

Document review and in-depth interviews with identified stakeholders were conducted. The framework of Health Policy Triangle was adapted to guide data collection and analysis in terms of context, actors, process and content. Stakeholder analysis examining actors’ position, power, role and interest and thematic analysis focusing on data coding and theme development were used.

Results

Shenzhen’s contextual factors include legislative authority under a unitary political system, economic developments and cultural values on immunization and sexuality. Stakeholders’ position and power could be explained by their role and interest in the Top-down health administration. Mothers could be potential bystanders if having little knowledge on HPV vaccination. Themes in policy-making process were problem definition, advocacy activities to promote HPV vaccination, HPV vaccine demand and access, the role of media and political attention on evidence-informed policy-making in Shenzhen. These stakeholders also discussed different aspects of program planning prospectively.

Conclusions

Shenzhen witnesses a possibility of demonstration projects for local government’s horizontal accountability but no potential advocates were identified at local level for fragmented organization of public health facilities and health professionals’ lacking mobilization skills. A cervical cancer prevention expert could be a policy entrepreneur. Despite of these challenges, the recommendations to enhance the feasibility include multi-participation to engage non-governmental organizations, pharmaceuticals, target girls and their mothers, power enforcement along governing system, as well as better use of the media.