Cost-effectiveness of HPV vaccination in the context of high cervical cancer incidence and low screening coverage

BackgroundEstonia has high cervical cancer incidence and low screening coverage. We modelled the impact of population-based bivalent, quadrivalent or nonavalent HPV vaccination alongside cervical cancer screening.MethodsA Markov cohort model of the natural history of HPV infection was used to assess the cost-effectiveness of vaccinating a cohort of 12-year-old girls with bivalent, quadrivalent or nonavalent vaccine in two doses in a national, school-based vaccination programme. The model followed the natural progression of HPV infection into subsequent genital warts (GW); premalignant lesions (CIN 1–3); cervical, oropharyngeal, vulvar, vaginal and anal cancer. Vaccine coverage was assumed to be 70%. A time horizon of 88 years (up to 100 years of age) was used to capture all lifetime vaccination costs and benefits. Costs and utilities were discounted using an annual discount rate of 5%.ResultsVaccination of 12-year-old girls alongside screening compared to screening alone had an incremental cost-effectiveness ratio (ICER) of €14,007 (bivalent), €14,067 (quadrivalent) and €11,633 (nonavalent) per quality-adjusted life-year (QALY) in the base-case scenario and ranged between €5367–21,711, €5142–21,800 and €4563–18,142, respectively, in sensitivity analysis. The results were most sensitive to changes in discount rate, vaccination regimen, vaccine prices and cervical cancer screening coverage.ConclusionVaccination of 12-year-old girls alongside current cervical cancer screening can be considered a cost-effective intervention in Estonia. Adding HPV vaccination to the national immunisation schedule is expected to prevent a considerable number of HPV infections, genital warts, premalignant lesions, HPV related cancers and deaths. Although in our model ICERs varied slightly depending on the vaccine used, they generally fell within the same range. Cost-effectiveness of HPV vaccination was found to be most dependent on vaccine cost and duration of vaccine immunity, but not on the type of vaccine used.     

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

ObjectivesTo assess the effectiveness of the HPV vaccines in preventing genital warts (GW) in women aged 14–23 years and to estimate the incidence of GW in the whole population aged from 14 to 65.DesignPopulation-based retrospective cohort study using real-world data from the Valencia health system Integrated Databases (VID).Study populationAll subjects aged 14–65 years residing in the Valencia Region during 2009–2017 (n = 4,492,724), including a cohort of 563,240 females aged 14–23 years followed-up for the vaccine effectiveness (VE) estimations.Main outcome measuresIncident cases of GW defined as the first activation of GW-related codes (ICD-9-CM 078.11 or ICD-10-CM A63.0) in hospital, primary and specialized care during the study period. Adjusted VE was estimated as (1-Relative Risk (RR)) × 100 by a negative binomial Bayesian model.ResultsThere were 23,049 cases of GW in the overall population and 2,565 in the females’ cohort 14–23 years old. The incidence rate (IR) (in 100,000 persons-year) was 69.1 (95% CI 68.21–69.99) in the population overall, being higher in men (72.73; 95% CI 71.45–74.04). The IR of GW was 104.08 (95% CI 100.79–108.94) in the cohort of young women. The RR of GW increased with age from 14 to 21 years, reaching a plateau from 21 to 23. The VE of a complete schedule was 74% (95% CrI 68–79) for quadrivalent HPV vaccine (HPV4v). No effectiveness was seen with a full vaccination course with the bivalent HPV vaccine (HPV2v) in girls up to 21 years old. GW IR tends to be higher in unvaccinated cohorts covered by HPV4v vaccine than in unvaccinated cohorts not covered by HPV4v vaccine.ConclusionsA complete HPV4v vaccination schedule was 74% effective in reducing GW in our population. Our results also suggest an indirect protection to unvaccinated and HPV2v vaccinated girls.     

HPV vaccine acceptance among adolescent males and their parents in two suburban pediatric practices

PurposeTo measure HPV vaccine acceptance among unvaccinated adolescent males and parents and correlate acceptance with knowledge, awareness, and personal experience.MethodsAdolescent males ages 11–21 years old and their parents completed questionnaires measuring attitudes and knowledge about HPV vaccination and personal experience. Acceptance was defined as wanting the vaccine and conditional acceptance as wanting the vaccine if it would protect against genital warts or cervical cancer.ResultsAdolescent (n = 154) and parent (n = 121) vaccine acceptance was low (16% and 34%, respectively); however, conditional acceptance was higher. While adolescents had similar conditional acceptance for a vaccine against genital warts and cervical cancer, parents reported higher conditional acceptance for protection against genital warts. Independent predictors of acceptance included personal experience and demographic variables.ConclusionsHPV vaccine acceptance among adolescents and parents was low. Conditional acceptance levels highlight the importance of education about a few important benefits of HPV vaccination, which may increase vaccination rates.     

Relationship status impacts primary reasons for interest in the HPV vaccine among young adult women

IntroductionThe HPV vaccine prevents HPV-related cancers and genital warts, which cause significant morbidity and mortality in the US. The vaccine is targeted toward 11–12 year old males and females, but is recommended for “catch-up” vaccination until age 26 for females. Young adult females (18–26 years) represent a unique group that may face distinct barriers to HPV vaccination, one of which is relationship status. The purpose of this study was to assess how relationship status impacts interest in HPV vaccination and primary reasons for non-vaccination among 18–26 year old young adult women.MethodsThe National Health Interview Survey 2010 was examined among unvaccinated females, 18–26 years (N = 1457). A survey-weighted logistic regression analysis with conversion to prevalence ratios assessed how interest in the HPV vaccine (yes/no) was influenced by relationship status (married, living with a partner, other, single) among young adult women. A Rao-Scott chi-square test examined differences between primary reasons for non-vaccination and relationship status among HPV vaccine uninterested women.ResultsAmong unvaccinated women, 31.4% were interested in the HPV vaccine. Women who were living with a partner (PR = 1.45, 95%CI 1.06–1.90) and single (PR = 1.42, 95%CI 1.11–1.76) were significantly more likely than married women to be interested in the HPV vaccine, while controlling for socio-demographic and other known risk factors. Additionally, primary reasons for non-vaccination differed based on relationship status among uninterested women (p < 0.01). Women who were married were more likely to cite not needing the vaccine compared to never married women (p < 0.05).ConclusionRelationship status in young adulthood impacts HPV vaccine interest and decision-making among a national sample of women. Primary reasons for non-interest in the vaccine may be shaped by attitudes and knowledge about the HPV vaccine that differ by relationship status. Future research is needed to elucidate ways to overcome relationship status as a barrier to HPV vaccination.     

No increased risk of Guillain-Barré syndrome after human papilloma virus vaccine: A self-controlled case-series study in England

ObjectiveTo investigate the risk of Guillain-Barré syndrome (GBS) after human papilloma virus (HPV) vaccine given to 12–18 year old girls in England.MethodsHospital Episode Statistics (HES) were searched using data to March 2016 to identify incident cases of GBS in female patients aged from 11 to 20 years eligible to have received the HPV vaccine since its introduction as a 3 dose schedule in September 2008. Diagnosis was confirmed by the case’s general practitioner (GP) who also provided HPV vaccination dates. The risk of admission within 3 months (primary risk window) 6 and 12 months of any dose was assessed using the self-controlled case-series (SCCS) method in vaccinated girls with age, season and time-period adjustment. The risk before and after the change in 2012 from bivalent vaccine to quadrivalent vaccine was also assessed.ResultsA total 244 episodes were initially identified which reduced to 101 episodes in 100 girls when just including cases where the GP could be contacted, at least one vaccine dose was given, and GBS was confirmed or classed as probable. Nine, 14 and 24 GBS admissions occurred within 3, 6, 12 months of a dose respectively. The relative incidence (RI) for the 3 month risk period was 1.04 (95% confidence interval 0.47–2.28), for the 6 month period 0.83 (0.41–1.69) and for the 12 month period 1.10 (0.57–2.14). When restricting to 79 confirmed cases the RI in the 3 month risk period was 1.26 (0.55–2.92) and the RI 1.61 (0.39–6.54) for quadrivalent vaccine compared to 0.84 (0.30–2.34) for bivalent.ConclusionWe found no evidence of an increased risk of GBS following HPV vaccination in England and, based on the upper end of the 95% CI for the RI and the number of HPV vaccine doses given in England, can exclude a risk of about 1 per million doses.     

Safety and immunogenicity of a 9-valent HPV vaccine in females 12–26 years of age who previously received the quadrivalent HPV vaccine

ObjectivesTo assess the safety and immunogenicity of the investigational 9-valent (6/11/16/18/31/33/45/52/58) HPV (9vHPV) vaccine in prior recipients of a 3-dose regimen of quadrivalent (6/11/16/18) HPV (qHPV) vaccine.MethodsV503-006 was a randomized, double-blinded, safety/tolerability and immunogenicity study of the 9vHPV vaccine in females 12–26 years of age who were previously vaccinated with qHPV vaccine. Subjects were randomized in a 2:1 ratio to receive 3 doses of 9vHPV vaccine (n = 618) or saline placebo (n = 306) at day 1, month 2, and month 6. Systemic, injection-site and serious adverse experiences (AEs) were monitored. Serum samples were collected at day 1, month 2, and month 7. Anti-HPV 6/11/16/18/31/33/45/52/58 titers were measured using the 9-valent HPV competitive Luminex Immunoassay (cLIA).ResultsThe frequency of injection-site AEs (days 1–5 following any vaccination) was higher in the 9vHPV vaccine group than in the placebo group (91.1% and 43.9%, respectively). The frequencies of vaccine-related systemic AEs (days 1–15 following any vaccination) were generally comparable between the 2 groups (30.6% in the 9vHPV vaccine group, and 25.9% in the placebo group). One vaccine-related serious AE was reported in each of the 9vHPV vaccine and placebo groups. Few subjects (9vHPV = 0.5%; placebo = 0%) discontinued due to an AE. At 4 weeks post-dose 3, over 98% of subjects in the 9vHPV vaccine group were seropositive for HPV types 31/33/45/52/58, with marked elevations in cLIA geometric mean titers (GMTs) to these HPV types. Anti-HPV 31/33/45/52/58 GMTs were lower than in subjects administered 9vHPV vaccine who had not previously received qHPV vaccine (based on cross-study analyses); the clinical significance of this difference is unknown.ConclusionsAdministration of a 3-dose regimen of 9vHPV vaccine to adolescent girls and young women 12–26 years of age who are prior qHPV vaccine recipients is highly immunogenic with respect to HPV types 31/33/45/52/58 and generally well tolerated.     

Seropositivity to non-vaccine incorporated genotypes induced by the bivalent and quadrivalent HPV vaccines: A systematic review and meta-analysis

BackgroundHuman papillomavirus vaccines have demonstrated remarkable efficacy against persistent infection and disease associated with vaccine-incorporated genotypes and a degree of efficacy against some genetically related, non-vaccine-incorporated genotypes. The vaccines differ in the extent of cross-protection against these non-vaccine genotypes. Data supporting the role for neutralizing antibodies as a correlate or surrogate of cross-protection are lacking, as is a robust assessment of the seroconversion rates against these non-vaccine genotypes.MethodsWe performed a systematic review and meta-analysis of available data on vaccine-induced neutralizing antibody seropositivity to non-vaccine incorporated HPV genotypes.ResultsOf 304 articles screened, 9 were included in the analysis representing ca. 700 individuals. The pooled estimate for seropositivity against HPV31 for the bivalent vaccine (86%; 95%CI 78–91%) was higher than that for the quadrivalent vaccine (61%; 39–79%; p = 0.011). The pooled estimate for seropositivity against HPV45 for the bivalent vaccine (50%; 37–64%) was also higher than that for the quadrivalent vaccine (16%; 6–36%; p = 0.007). Seropositivity against HPV33, HPV52 and HPV58 were similar between the vaccines. Mean seropositivity rates across non-vaccine genotypes were positively associated with the corresponding vaccine efficacy data reported from vaccine trials.ConclusionsThese data improve our understanding of vaccine-induced functional antibody specificity against non-vaccine incorporated genotypes and may help to parameterize vaccine-impact models and improve patient management in a post-vaccine setting.     

HIV viral suppression results in higher antibody responses in HIV-positive women vaccinated with the quadrivalent human papillomavirus vaccine

ObjectiveTo evaluate the immunogenicity and safety of the quadrivalent HPV (qHPV) vaccine in HIV-positive women over 24 months.DesignBetween November 2008 and December 2012, 372 women aged 15 and older were enrolled from 14 Canadian HIV outpatient clinics in an open label cohort study. The qHPV vaccine (0.5 mL) was administered intramuscularly at months 0, 2 and 6. The primary study endpoint was seroconversion to any of the HPV types targeted by the qHPV vaccine. Antibody levels were measured at 0, 2, 7, 12, 18, and 24 months. Adverse events were recorded throughout.ResultsOf 372 participants enrolled, 310 (83%) received at least one dose of the qHPV vaccine and 277 (74%) received all three doses. Ninety-five percent (293/308) were seronegative for at least one vaccine type at baseline. The median age was 38 years (IQR 32–45, range 15–66), 36% were white, 44% black and 13% were of Indigenous origin. Seventy-two percent of participants had a suppressed HIV viral load (VL < 40 c/ml) at baseline, with a median CD4 count of 510 cells/mm³ (376–695). Month 7 HPV type-specific seroconversion rates were 99.0%, 98.7%, 98.1% and 93.6% for HPV types 6, 11, 16 and 18 respectively in the per-protocol population. Participants with suppressed HIV VL at first vaccine had a 1.74–3.05 fold higher peak antibody response compared to those without (p from 0.006 to <0.0001).ConclusionsThis study is the first to examine the qHPV vaccine in HIV-positive women out to 24 months and the first to include HIV-positive women through to age 66. The qHPV vaccine was well tolerated, and highly immunogenic. As women with suppressed viral load had higher antibody responses, planning HPV vaccination to occur when persons are virologically suppressed would be optimal for maximizing immune response. Findings provide strong evidence that older HIV-positive women can still benefit from HPV vaccination.Clinical trial registration: http://www.isrctn.com/ISRCTN33674451     

Reduction of HPV16/18 prevalence in young women after eight years of three- and two-dose vaccination schemes

BackgroundRecommendations for human papillomavirus vaccination have relied on immunogenicity studies and efficacy results derived from adult women. Insufficient information exists regarding HPV effectiveness in vaccinated girls as they become sexually active, regardless of dose scheme. We aimed to compare the prevalence of high-risk HPV between unvaccinated and vaccinated young women eight years after immunization.MethodsAfter eight years, we recontacted women who received two-dose of bivalent or three-dose—either bivalent or quadrivalent—, HPV vaccine when aged 9–10 years-old as part of a clinical trial. Additionally, we recruited a contemporaneous unvaccinated woman group for comparison. Only those sexually active were included. High-risk HPV DNA was determined in urine samples and compared across groups.ResultsThe prevalence of HPV16/18 types was 6.8% (95 %CI 3.2–14.1%) in the unvaccinated (n = 6/88), 1.1% (95 %CI 0.2–5.8%) in the three-dose (n = 1/93), and 0.0% (95 %CI 0.0–7.0%) in the two-dose group (n = 0/51).ConclusionHPV vaccination, with two-dose of bivalent or three-dose schemes—either with the bivalent or quadrivalent vaccine—, was associated with a lower prevalence of HPV16/18 types eight years after primary immunization.     

Monitoring human papillomavirus prevalence among young Australian women undergoing routine chlamydia screening

IntroductionAustralia has recently implemented major changes in cervical cancer prevention policies including introduction of primary human papillomavirus (HPV) screening starting at age 25, and replacement of the quadrivalent HPV vaccine with the nonavalent vaccine in the national school-based program. We assessed the feasibility and utility of conducting HPV testing in residual clinical specimens submitted for routine Chlamydia trachomatis screening, as a means of tracking HPV vaccine program impact among young sexually active women.MethodsDe-identified residual specimens from women aged 16–24 years submitted for chlamydia testing were collected from three pathology laboratories in Victoria and New South Wales. Limited demographic information, and chlamydia test results were also collected. Patient identifiers were sent directly from the laboratories to the National HPV Vaccination Program Register, to obtain HPV vaccination histories. Samples underwent HPV genotyping using Seegene Anyplex II HPV 28 assay.ResultsBetween April and July 2018, 362 residual samples were collected, the majority (60.2%) of which were cervical swabs. Demographic data and vaccination histories were received for 357 (98.6%) women (mean age 21.8, SD 2.0). Overall, 65.6% of women were fully vaccinated, 9.8% partially, and 24.7% unvaccinated. The majority (86.0%) resided in a major city, 35.9% were classified in the upper quintile of socioeconomic advantage and chlamydia positivity was 7.8%. The prevalence of quadrivalent vaccine-targeted types (HPV6/11/16/18) was 2.8% (1.5–5.1%) overall with no differences by vaccination status (p = 0.729). The prevalence of additional nonavalent vaccine-targeted types (HPV31/33/45/52/58) was 19.3% (15.6–23.8%). One or more oncogenic HPV types were detected in 46.8% (95% CI 41.6–52.0%) of women.ConclusionsHPV testing of residual chlamydia specimens provides a simple, feasible method for monitoring circulating genotypes. Applied on a larger scale this method can be utilised to obtain a timely assessment of nonavalent vaccine impact among young women not yet eligible for cervical screening.     

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

BackgroundThe 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.MethodsPubMed 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.ResultsData 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.ConclusionsRCTs 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.     

Reduction in HPV 16/18-associated high grade cervical lesions following HPV vaccine introduction in the United States – 2008–2012

BackgroundPrevention of pre-invasive cervical lesions is an important benefit of HPV vaccines, but demonstrating impact on these lesions is impeded by changes in cervical cancer screening. Monitoring vaccine-types associated with lesions can help distinguish vaccine impact from screening effects. We examined trends in prevalence of HPV 16/18 types detected in cervical intraepithelial neoplasia 2, 3, and adenocarcinoma in situ (CIN2+) among women diagnosed with CIN2+ from 2008 to 2012 by vaccination status. We estimated vaccine effectiveness against HPV 16/18-attributable CIN2+ among women who received ≥1 dose by increasing time intervals between date of first vaccination and the screening test that led to detection of CIN2+ lesion.MethodsData are from a population-based sentinel surveillance system to monitor HPV vaccine impact on type-specific CIN2+ among adult female residents of five catchment areas in California, Connecticut, New York, Oregon, and Tennessee. Vaccination and cervical cancer screening information was retrieved. Archived diagnostic specimens were obtained from reporting laboratories for HPV DNA typing.ResultsFrom 2008 to 2012, prevalence of HPV 16/18 in CIN2+ lesions statistically significantly decreased from 53.6% to 28.4% among women who received at least one dose (P_trend < .001) but not among unvaccinated women (57.1% vs 52.5%; P_trend = .08) or women with unknown vaccination status (55.0% vs 50.5%; P_trend = .71). Estimated vaccine effectiveness for prevention of HPV 16/18-attributable CIN2+ was 21% (95% CI: 1–37), 49% (95% CI: 28–64), and 72% (95% CI: 45–86) in women who initiated vaccination 25–36 months, 37–48 months, and >48 months prior to the screening test that led to CIN2+ diagnosis.ConclusionsPopulation-based data from the United States indicate significant reductions in CIN2+ lesions attributable to types targeted by the vaccines and increasing HPV vaccine effectiveness with increasing interval between first vaccination and earliest detection of cervical disease.     

HPV vaccination coverage of teen girls: The influence of health care providers

BackgroundBetween 2010 and 2014, the percentage of 13–17 year-old girls administered ≥3 doses of the human papilloma virus (HPV) vaccine (“fully vaccinated”) increased by 7.7 percentage points to 39.7%, and the percentage not administered any doses of the HPV vaccine (“not immunized”) decreased by 11.3 percentage points to 40.0%.ObjectiveTo evaluate the complex interactions between parents’ vaccine-related beliefs, demographic factors, and HPV immunization status.MethodsVaccine-related parental beliefs and sociodemographic data collected by the 2010 National Immunization Survey-Teen among teen girls (n = 8490) were analyzed. HPV vaccination status was determined from teens’ health care provider (HCP) records.ResultsAmong teen girls either unvaccinated or fully vaccinated against HPV, teen girls whose parent was positively influenced to vaccinate their teen daughter against HPV were 48.2 percentage points more likely to be fully vaccinated. Parents who reported being positively influenced to vaccinate against HPV were 28.9 percentage points more likely to report that their daughter's HCP talked about the HPV vaccine, 27.2 percentage points more likely to report that their daughter's HCP gave enough time to discuss the HPV shot, and 43.4 percentage points more likely to report that their daughter's HCP recommended the HPV vaccine (p < 0.05). Among teen girls administered 1–2 doses of the HPV vaccine, 87.0% had missed opportunities for HPV vaccine administration.ConclusionResults suggest that an important pathway to achieving higher ≥3 dose HPV vaccine coverage is by increasing HPV vaccination series initiation though HCP talking to parents about the HPV vaccine, giving parents time to discuss the vaccine, and by making a strong recommendation for the HPV. Also, HPV vaccination series completion rates may be increased by eliminating missed opportunities to vaccinate against HPV and scheduling additional follow-up visits to administer missing HPV vaccine doses.     

Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines

Ninety-one HIV-infected individuals (61 men and 30 women) were randomized to vaccination either with quadrivalent (Gardasil™) or bivalent (Cervarix™) HPV vaccine. Neutralizing and specific HPV-binding serum antibodies were measured at baseline and 12 months after the first vaccine dose. Presence of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were <1 international unit (IU) in 87% of study subjects before vaccination but >10 IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil™ vaccination for >50% of vaccinated females for HPV 31, 35 and 73 and for >50% of Cervarix™-vaccinated females for HPV 31, 33, 35, 45, 56 and 58. Cross-reactivity with non-genital HPV types was also detected. In conclusion, HIV-infected subjects responded to HPV vaccination with induction of neutralizing antibodies against both vaccine and non-vaccine types.     

Human papillomavirus vaccination: Assessing knowledge,attitudes, and intentions of college female students in Lebanon,a developing country

Human papillomavirus (HPV) infection is a common cause for genital warts and cervical cancer. Developing countries in the Middle East such as Lebanon are traditionally considered to be conservative societies with low incidence of sexually transmitted infections. However, nowadays, there is an unexpected increase in the incidence of HPV infections among Middle Eastern females. Thus, the objective of this study is to assess the behavioral perceptions of HPV vaccination among female students attending an academic institution in Lebanon. This cross-sectional study invited 512 students to complete a self-administered questionnaire that assessed the knowledge, attitudes, and intentions towards HPV vaccination. Data analysis included the calculation of knowledge scores ranging from 0 to 100, attitude scores ranging from most positive (1) to most negative (5), and intention scores ranging from lowest intention (0) to highest intention (10). With a response rate of n = 215 (42%), 36.5% never heard of the vaccine before, and only 16.5% were already HPV vaccinated. The median knowledge score of 52.7% ± 1.71 reflects poor to moderate knowledge. Still, the median attitude score of 2.47 ± 0.05 shows a general positive attitude towards HPV vaccination where most of the participants agreed that female college students in Lebanon have a good chance of contracting HPV (62.1%) and that all gynecologists should recommend the vaccine (76.0%). Students in graduate programs, health related majors, and those who are vaccinated had significantly higher knowledge scores compared with students in undergraduate programs, non-health related majors, and HPV non-vaccinated students, respectively. Finally, the survey helped in increasing the intention to obtain HPV vaccine as the intention score increased significantly from 5.24 ± 0.27 before the students went through the survey to 6.98 ± 0.22 after the students completed the survey. Our study highlights the importance of offering guidance to female college students about HPV and its vaccination in developing countries where the incidence of sexually transmitted infections is on the rise.     

Missed opportunities for catch-up human papillomavirus vaccination among university undergraduates: Identifying health decision-making behaviors and uptake barriers

BackgroundSuboptimal adolescent human papillomavirus (HPV) vaccine rates in the US highlight the need for catch-up vaccination. When teenagers enter college, there may be a shift in healthcare decision-making from parents and guardians to the students themselves. Little is known about factors influencing college students’ healthcare decision-making processes.Study designWe evaluated HPV vaccine decision-making among 18-to-26-year-old college students through a self-administered, anonymous, cross-sectional survey. This survey was distributed to a sample of men and women in classroom settings at two universities. Categorical data comparisons were conducted using Chi-square and Fisher’s exact tests. Multivariate Poisson regression was used to model initiation of HPV vaccine and compute prevalence ratios while controlling for key influential covariates at the 0.05 alpha level.ResultsA total of 527 students participated (response proportion = 93.1%). Overall, 55.8% of participants received the HPV vaccine. Encouraging conversations with doctors and/or parents/guardians were identified as one of the most influential factors to increase vaccine uptake. Among students who received encouragement from both a doctor and parent, 95.8% received the vaccine. Campaigns about cancer prevention were viewed as more influential than those that focus on preventing genital warts. Approximately one-third of students indicated they didn’t know where to get the HPV vaccine. Women were more likely to report that their parents would not let them get the HPV vaccine compared to men (26.7% vs. 2.3%). The majority of students (77.3%) indicated their parents were sometimes, equally, or mostly involved in making decisions about receiving vaccines (other than flu).ConclusionStudents’ decision-making is greatly influenced by their parents; therefore, interventions for this population should work to increase students’ control over decision-making while also addressing parental concerns.     

Effect of number of human papillomavirus vaccine doses on guideline adherent cervical cytology screening among 19–26 year old females

PurposeLittle is known about how the number of HPV vaccine doses affect adherence to screening guidelines. This study compared adherence to cervical cancer screening by the number of HPV vaccine doses received by young women and assessed whether the specialty of vaccinating providers affected behavior.MethodsThis retrospective cohort study using administrative insurance claims records included 24,964 19–26 year old women who received at least 1 injection of the HPV vaccine between January 2006 and November 2009. Vaccinated young women continuously enrolled in a nationally-representative private insurance plan for 6 months prior to and 37 months after HPV vaccine administration were included. Logistic regression was used to compare the odds of Papanicolaou (Pap) testing 3 years after vaccine initiation by number of vaccine doses and provider type.ResultsIn this sample, 79.3% had a Pap test 3 years following vaccine initiation. Receiving 1 (aOR: 0.60, 95% CI 0.55–0.65) or 2 (aOR: 0.80, 95% CI 0.74–0.87) doses was associated with decreased odds of Pap testing compared to 3 doses. Many young women in our sample (16.5%) were diagnosed with cervical dysplasia prior to HPV vaccination. Patients vaccinated by non-obstetrician/gynecologists were less likely to get a Pap test following vaccination.ConclusionsWomen who received 1 or 2 doses of the HPV vaccine were less likely than those who received 3 doses to be screened for cervical cancer 3 years following vaccine initiation. Pediatricians and primary care physicians should convey the importance of initiating and continuing screening to HPV vaccinated patients.     

Adolescent and young adult HPV vaccination in Australia: Achievements and challenges

Australia commenced an ongoing school based government funded human papillomaviruses (HPV) (cervical cancer prevention) vaccination program in April 2007 for adolescent females aged 12–13 years. In addition, up to December 31, 2009, a catch-up program for young females 13–26 years of age was offered: a school-based vaccination program was used to offer HPV vaccine to girls enrolled in school (14–17 years), and general practitioners or other community health provider offered vaccine to young women aged 18–26 years. To date, only the quadrivalent vaccine (HPV 6/11/16/18) has been utilized in the funded program. Acceptance of the vaccine is high with coverage of 3 doses of the HPV vaccine in the school age cohort around 70%, and just over 30% in the older age cohort. Since the vaccination program was initiated, a reduction in new cases of genital warts of 73% among vaccine eligible age females has been evidenced in STI clinics across Australia. A reduction of 44% of new cases in young males (not a part of the free program) was also documented during this same time period, suggesting significant herd immunity. Similarly, in the state of Victoria, a small but significant decrease in high grade abnormalities in Pap screening findings has been reported in young women < 18 years for the period 2007–9, as compared to pre-vaccination. Challenges for the future include how we can sustain and improve HPV vaccination coverage in young Australian women, while maintaining cervical cancer screening participation and reviewing cervical cancer screening methods.     

Impact of quadrivalent human papillomavirus vaccine in women at increased risk of genital warts burden: Population-based cross-sectional survey of Czech women aged 16 to 40 years

BackgroundTo assess the impact of a quadrivalent human papillomavirus vaccine (4HPV) in women at increased risk of genital warts (GWs) acquisition.MethodsThe study was conducted using a population-based cross-sectional survey of 19,199 women aged 16 to 40 years randomly chosen from the general population in the Czech Republic between January 2013 and March 2014. A total of 1086 women reported having received the 4HPV vaccine. The vaccine's effectiveness was estimated not only in the general population of women but also in those at increased risk due to having a sexual partner with GWs or prior GWs history.ResultsThe acquisition of GWs was dramatically reduced by 90.6% (80.1–95.6%) in immunised women at least one year after the completion of the 4HPV vaccination in comparison with unimmunised women. Recurrent GWs prevalences of 1.1% (95% CI, 0.0–5.9) and 10.9% (95% CI, 9.1–12.9) in immunised and unimmunised women with prior GWs history, respectively, resulted in a vaccine effectiveness of 89.0% (38.6–98.0%). The notably strong protective effect of 4HPV immunisation in women who had a sexual partner with GWs was demonstrated by a very low age-adjusted odds ratio of 0.02 (95% CI 0.01–0.10) in contrast to unimmunised women.ConclusionsTo lower the chance of genital warts acquisition in the general population and in populations at increased risk, only current 4HPV or incoming 9HPV vaccination should be recommended to provide effective protection.     

Factors related to vaccine uptake by young adult women in the catch-up phase of the National HPV Vaccination Program in Australia: Results from an observational study

BackgroundAustralia commenced a publically-funded, National Human Papillomavirus (HPV) Vaccination Program in 2007 with a two year catch-up phase for females aged 12–26 years.ObjectiveTo identify the factors associated with the uptake of the HPV vaccine (which has a recommended 3-dose schedule in Australia) by young adult women vaccinated by general practitioners and community-based programs within the catch-up phase.Methods1139 women who were eligible to receive the free HPV vaccine during the catch-up period were recruited in 2008–2009 (age 20–29 years at recruitment), in New South Wales, after having a normal (negative) cervical smear result recorded on the NSW Pap Test Register. Participants completed a self-administered questionnaire providing information on vaccination status, and sociodemographic and other factors.ResultsOverall, 880 (77%) women reported receiving ≥1 dose of the vaccine and 777 women (68%) reported receiving ≥2 doses. In multivariable analysis (adjusting for the period for which each woman was eligible for free HPV vaccination), uptake of ≥1 dose of the vaccine was significantly associated with being born in Australia (p < 0.01), being single (p = 0.02), being nulliparous (p < 0.01), living in a higher socioeconomic status area (p-trend = 0.03), living in more remote areas (p = 0.03), drinking alcohol (p < 0.01) and using hormonal contraceptives (p < 0.01). Although vaccinated women were more likely to have fewer sexual partners than unvaccinated women (p-trend = 0.02), they were also more likely to report a prior sexually transmitted infection (STI) (p = 0.03). Similar factors were associated with receiving ≥2 doses.ConclusionsIn this group, women living in higher socioeconomic status areas were more likely to be vaccinated against HPV in the catch-up phase of the national program. Although vaccinated women tended to have fewer sexual partners, they also reported prior STIs, which may be a marker of increased risk of prior exposure to HPV. The findings of this study reinforce the continuing need to prioritise equitable delivery of vaccination to various population subgroups.