Population-level sexual behaviours in adolescent girls before and after introduction of the human papillomavirus vaccine (2003-2013)

Human Papillomavirus Vaccination in Pediatric, Adolescent, and Young Adult Cancer Survivors-Opportunity to Address Gaps in Cancer Prevention and Survivorship

The risks of secondary cancers associated with human papillomavirus (HPV) infection are as much as three times higher for survivors of pediatric, adolescent, and young adult cancer (PYAC) compared to the general population. Despite this, HPV vaccination rates among PYAC survivors remain low. Whereas pediatric oncology providers endorse HPV vaccination of PYAC survivors, many lack the resources or opportunities to intervene. The responsibility of HPV vaccination, therefore, falls to primary care providers and practices. This article provides an overview of the challenges with HPV vaccination that are distinct to PYAC survivors and discusses potential strategies to increase HPV vaccine coverage in this population.

Vaccination and risky behaviors: evidence from the hepatitis B vaccination campaign in China

Understanding the causal relationship between vaccination and individuals' risky behavioral responses has important policy implications as it affects the ultimate effectiveness of increasing access to vaccination. This paper examines the causal effects of vaccination on risky behaviors by exploring the 1992 hepatitis B vaccination campaign in China. Our empirical strategy exploits variations in age at the campaign as well as the pretreatment infection risks across provinces. Using a large cross-section of individuals born between 1981 and 1994, we find that more exposure to the hepatitis B vaccination leads to lower alcohol use during adulthood, and such impacts are almost entirely driven by men. Individuals from more educated families and people who live in urban areas tend to react more. Improved educational attainment and dissemination of related knowledge are important contributors. Our results uncover an unexpected benefit of promoting access to vaccination.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00148-023-00942-4.

Evidence-Based Practice Model to Increase Human Papillomavirus Vaccine Uptake: A Stepwise Approach

OBJECTIVE

To increase uptake of human papillomavirus (HPV) vaccination by implementing a stepwise evidence-based practice model to offer HPV education along with a strong provider recommendation to parents of youth and adolescents.

DESIGN

Evidence-based practice change model.

SETTING

A nurse practitioner-run, primary care walk-in clinic in a rural area of the southeastern United States.

PARTICIPANTS

Parents of youth and adolescents ages 11 to 17 years.

INTERVENTIONS/MEASUREMENTS

Education targeting parental hesitancy and strong recommendations for immunization was administered by health care providers to parents of youth and adolescents eligible for vaccination. The Parent Attitudes About Childhood Vaccine instrument was used to identify the presence and degree of parental hesitancy. Vaccination uptake was measured and compared to the same time period from the previous year.

RESULTS

Data collected from the clinic vaccination log during the same 6-week time period in 2018 identified that four youth/adolescents were vaccinated with the HPV vaccine in 2018. During the same 6-week period in 2019 when the practice change was implemented, 38 parents were approached; 24 met eligibility criteria, and all 24 of their youth/adolescents received HPV vaccination.

CONCLUSION

Implementation of an evidence-based practice model that includes standing vaccine orders and reminders and recalls may provide an effective way to ensure completion of the HPV vaccine series. Every missed clinical opportunity to vaccinate youth and adolescents against HPV can contribute to lower vaccination rates and increased risk for genital warts and cancers associated with HPV infection.

Effect of human papilloma virus vaccination on sexual behaviours among adolescent women in Rwanda: a regression discontinuity study

Increasing human papilloma virus (HPV) vaccination coverage is one of the key approaches to preventing cervical cancer globally. However, some argue that HPV vaccine recipients may engage in risky compensatory sexual behaviours because of perceived protection afforded by the vaccine. Therefore, we investigated the impact of a wide-scale HPV vaccination programme on sexual behaviours among adolescent women in Rwanda-the first African country to implement a national HPV vaccination. We identified a cohort of women who were eligible for the HPV vaccination and those who were not eligible from the most recent Rwanda Demographic and Health Survey. We used a quasi-experimental regression discontinuity design, exploiting the quasi-random change in HPV vaccination eligibility in 2011, to compare sexual behaviours among vaccinated and unvaccinated adolescent women. We studied the impact of the vaccination on reported sexual intercourse, average number of sexual partners and teenage pregnancy across the vaccination eligibility threshold. Our analysis included 3052 adolescent women (mean age: 18.6 years), of whom 58% were eligible for HPV vaccination. Nearly one in five adolescents reported having had sexual intercourse (18.5%). The average reported lifetime number of sexual partners was 1.41. The proportion of teenage pregnancy was 5.3%. We found no evidence that HPV vaccination was associated with any significant changes across the eligibility threshold in reported sexual behaviours we studied: no significant increase in the proportion of having sexual intercourse [odds ratio (OR): 0.80, 95% confidence interval (CI): 0.57-1.12; P = 0.19], in lifetime number of sexual partners (rate ratio 0.99, 95% CI: 0.83-1.17, P = 0.91) and in the proportion of teen pregnancies (OR 1.05, 95% CI: 0.50 to 2.20, P = 0.89) at the eligibility threshold. The Rwandan national HPV vaccination programme did not increase sexual behaviours among adolescent women, assuaging concerns of engaging in risky compensatory sexual behaviours some have feared.

Evaluation of the acceptability in France of the vaccine against papillomavirus (HPV) among middle and high school students and their parents

BACKGROUND

The pathogenic and oncogenic roles of papillomavirus (HPV) infections have been documented and shown to occur in women as well as in men. While other countries have already extended their vaccination guidelines to include boys, in 2019 the French National Authority for Health validated implementation of HPV vaccination in the 2020 vaccination schedule. There is, however, a climate of distrust in regard to vaccination in France, and there have been few studies to date regarding the acceptability of HPV vaccination in boys in France. The aim of this study was, therefore, to evaluate the acceptability of extending the recommendations for HPV vaccination in men, among middle and high school students and their parents.

METHODS

Our study (HPVac) was a prospective, multicenter, departmental, and descriptive survey applied to a sample of male middle and high school students attending schools in the Loire-Atlantique department and their parents. It took place from January 2017 to January 2018.

RESULTS

We analyzed the information obtained from 127 parent questionnaires and 145 children questionnaires. In terms of acceptability, 36.6% (n = 53) of the children and 37.8% (n = 48) of the parents were in favour of being vaccinated or of having their children vaccinated against HPV (51.7% (n = 75) and 50.4% (n = 64), respectively, were undecided). The perception of a risk stemming from HPV infection was positively associated with acceptability of the HPV vaccine. Being against vaccines in general, being discouraged by their parents, parents thinking that their child is not at risk, and the belief that the vaccine is not mandatory were arguments cited and significantly associated with a willingness to be vaccinated.

CONCLUSION

This study revealed a lack of information among boys and their parents about HPV and its vaccination. It also clearly showed that taking time to discuss the consequences of an infection and the merits of being vaccinated can help parents overcome their reluctance. The children then generally go along with their parent's choice.

Factors associated with interest in bacterial sexually transmitted infection vaccines at two large sexually transmitted infection clinics in British Columbia, Canada

Objective

To explore sexually transmitted infection (STI) clinic client attitudes and preferences towards STI vaccines and STI vaccine programming in an urban clinic setting.

Methods

A 31-item questionnaire was administered during check-in by clinic clerical staff at two STI clinics in Vancouver, Canada. Demographic characteristics and preferences were summarised descriptively. Multivariable logistic regression models to assess factors associated with STI vaccine interest (reported as ORs) were constructed using a priori clinically relevant variables and factors significant at p≤0.05 in bivariate analysis.

Results

293 surveys were included in analysis. 71.3% of respondents identified as male, 80.5% had college level education or higher and 52.9% identified as white/of European descent. The median age was 33. 86.5% of respondents reported they would be interested in receiving an STI vaccine, with a primary motivator to protect oneself. Bivariate analysis indicated several factors associated with vaccine interest, with differences for each infection. After adjusting for other variables, willingness to pay for an STI vaccine (OR=3.83, 95% CI 1.29 to 11.38, p=0.02) remained a significant factor for syphilis vaccine interest and intent to engage in future positive health behaviours remained a significant factor for chlamydia (OR=5.94, 95% CI 1.56 to 22.60, p=0.01) and gonorrhoea (OR=5.13, 95% CI 1.45 to 18.07, p=0.01) vaccine interest.

Conclusion

Respondents expressed a strong willingness to receive STI vaccines. These valuable findings will inform for eventual STI vaccine programme planning and implementation.

Sexual Behavior Patterns and Condom Use in Newly Sexually Active Female University Students

Our objective was to describe sexual behavior patterns and condom use in newly sexually active female university students. We conducted a 4-year retrospective cohort study (2000-2007) of university women enrolled close to sexual debut (N = 250). Participants reported daily information on intercourse, condom use, and partner/partnership characteristics into Web-based biweekly sexual behavior diaries. We calculated intercourse frequency, proportion of condom-protected events, and incidence of new partner acquisition. We used logistic regression to examine factors associated with condom use at sexual debut; Kaplan-Meier methods to describe cumulative incidence of condom non-use after use at debut; and Cox proportional hazards ratios to examine factors associated with condom non-use. A total of 188 women had at least one male sex partner prior to enrollment or during follow-up. One-third (34.1%) of 27,736 intercourse events were condom-protected. Older age (20+ vs. < 20 years) and use of hormonal birth control were associated with lower likelihood of condom use at sexual debut (adjusted odds ratio [aOR] 0.41, 95% CI 0.17-0.97 and aOR 0.32, 95% CI 0.10-1.03, respectively). Women who reported partners with previous sex partners were less likely to discontinue using condoms after debut (hazard ratio = 0.35, 0.16-0.77) than those reporting partners without previous partners. In college-aged women, older age and hormonal contraceptive use were each inversely associated with condom use at first intercourse. Women with sexually experienced partners were more likely to continue using condoms. Continued efforts are necessary to promote condom use among college-aged women.

Declines in Vaccine-Type Human Papillomavirus Prevalence in Females Across Racial/Ethnic Groups: Data From a National Survey

PURPOSE

To monitor human papillomavirus (HPV) vaccine impact in the U.S., we evaluated quadrivalent vaccine (4vHPV)-type prevalence among females aged 14-34 years in the prevaccine (2003-2006) and vaccine (2013-2016) eras overall and by race/ethnicity in the National Health and Nutrition Examination Survey.

METHODS

We analyzed HPV DNA prevalence in self-collected cervicovaginal specimens, demographic characteristics, sexual behavior, and self-reported/parent-reported vaccination status. We compared prevaccine to vaccine era 4vHPV-type prevalence, using unadjusted and adjusted prevalence ratios (PR and aPR) and 95% confidence intervals (CIs). PRs were calculated by race/ethnicity (non-Hispanic white [NHW], non-Hispanic black [NHB], and Mexican American [MA]). Overall aPRs were adjusted for race/ethnicity, lifetime sex partners, and poverty.

RESULTS

Overall, 4,674 females had HPV typing results; 3,915 reported NHW, NHB, or MA race/ethnicity. Vaccination coverage of ≥1 dose was 53.9% among 14- to 19-year-olds (NHW 52.6%, NHB 58.1%, and MA 59.5%) and 51.5% among 20- to 24-year-olds (NHW 58.8%, NHB 45.0%, MA 33.8%). Among 14- to 19-year-olds, 4vHPV-type prevalence decreased overall (11.5% to 1.8%; aPR = .14 [CI: .08-.24]) and in NHW (PR = .14 [CI: .06-.29]), NHB (PR = .26 [CI: .12-.54]), and MA (PR = .13 [CI: .03-.53]). In 20- to 24-year-olds, 4vHPV-type prevalence decreased overall (18.5% to 5.3%; aPR = .29 [CI: .15-.56]) and in NHW (PR = .27 [CI: .11-.67]) and NHB (PR = .38 [CI: .18-.80]). No significant declines were observed in older age groups.

CONCLUSIONS

Within 10 years of vaccine introduction, 4vHPV-type prevalence declined 86% among 14- to 19-year-olds, with declines observed in NHW, NHB, and MA females, and 71% among 20- to 24-year-olds, with declines in NHW and NHB females. These extraordinary declines should lead to substantial reductions in HPV-associated cancers.

Sexual behaviors and intention for cervical screening among HPV-vaccinated young Chinese females

BACKGROUND AND OBJECTIVES

Human papillomavirus (HPV) vaccination and cervical screening prevent cervical cancer effectively. However, there are concerns whether vaccination leads to high-risk sexual behaviors and less intention for cervical screening. We aimed to evaluate the influence of HPV vaccination on high-risk sexual behaviors, and intention for cervical screening among young Chinese females. We also reported the latest HPV vaccination uptake in Hong Kong.

METHODS

A population-based survey was conducted between September 2016 and January 2017. Subjects were school-age girls from twenty-five secondary schools (in-school) and community females between 18 and 27 years (out-school). Demographics, vaccine-related attitudes, intention for cervical screening and participants' sexual behaviors were examined.

RESULTS

We surveyed 2260 females from in-school (n = 1664) and out-school (n = 596) settings. 11.5% in-school and 23.5% out-school participants received at least one dose of HPV vaccine. Vaccination was not associated with age (in-school Odds Ratio [OR] 0.99, p = 0.87; out-school OR 1, p = 0.94), ethnicity (in-school OR 0.82, p = 0.72; out-school OR 0, p = 0.98), maternal education (in-school OR for secondary school 1.19, p = 0.43; for post-secondary school 1.28, p = 0.48), underage sex (in-school OR 1.22, p = 0.80; out-school OR 0.63, p = 0.67), earlier sexual exposure (in-school β 0.01, p = 0.99; out-school β 0.13, p = 0.68), multiple sex partners (in-school OR 3.27, p = 0.22; out-school OR 1.16, p = 0.43), and unprotected sex (in-school OR 1.14, p = 0.78; out-school OR 0.60, p = 0.10). Out-school females with higher personal education level was associated with higher vaccine uptake (post-secondary OR 3.4, p < 0.001; bachelor's degree or above OR 3.71, p < 0.001). More vaccinated females intended for cervical screening (in-school 23.6% vs. 21.1%; out-school 53.6% vs. 43.6%). Costs and knowledge were important factors for non-vaccination and non-intention for cervical screening.

CONCLUSIONS

HPV vaccination was not associated with earlier and high risk sexual behavior among Chinese young females. Vaccinated Chinese young females had a higher intention for cervical screening.

HPV vaccination has not increased sexual activity or accelerated sexual debut in a college-aged cohort of men and women

Background

The human papillomavirus (HPV) is the most common sexually transmitted infection and is linked to several types of cancer. HPV vaccination uptake in the U.S. is relatively low, despite the vaccine’s high efficacy. Some parents of adolescents have concerns that vaccination will encourage sexual behavior and therefore choose not to vaccinate. Previous studies investigating vaccination and sexual behavior have included only young women and girls.

Methods

The objective of this study is to assess associations between HPV-vaccination and sexual behavior in a college-age cohort of both men and women. We analyzed questionnaire data collected from the Michigan HPV and Oropharyngeal Cancer Study, a cohort study designed to investigate HPV infection and its association with sexual behavior (data collected 2015–17, Ann Arbor, MI). Here, we consider vaccination status, sexual behavior, and substance use among 241 college-aged men and women. Logistic, Poisson, and Cox regression were used to determine the relationship between probability of sexual debut, number of sexual partners, and HPV vaccination status at baseline as well as between age at sexual debut and vaccination status at debut.

Results

HPV vaccination status was not significantly associated with an increased likelihood of sexual debut (odds ratio: 0.80 (95% CI: 0.41–1.58), decreased age of sexual debut (hazard ratio: 0.81 (95% CI: 0.65–1.00), nor an increased number of sexual partners (per year sexually active; incidence rate ratio: 1.27 (95% CI: 0.86–1.87)) in this cohort, after controlling for age, race, sex, and substance use. Instead, race or alcohol use were independent predictors of sexual behavior.

Conclusions

Concerns about the influence of the HPV vaccine on sexual behavior are likely unfounded for both men and women. These results can aid in increasing vaccine acceptability, inform and strengthen physician recommendations, and ultimately reduce the burden of HPV and HPV-related cancers in the U.S.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7134-1) contains supplementary material, which is available to authorized users.