Browsing by Subject "Papillomavirus Infections"

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    Population-level impact and herd effects following human papillomavirus vaccination programmes: a systematic review and meta-analysis
    (Elsevier, 2015-05) Drolet, Mélanie; Bénard, Élodie; Boily, Marie-Claude; Ali, Hammad; Baandrup, Louise; Beddows, Simon; Brisson, Jacques; Brotherton, Julia M.L.; Cummings, Teresa; Donovan, Basil; Fairley, Christopher K.; Flagg, Elaine W.; Johnson, Anne M.; Kahn, Jessica A.; Kavanagh, Kimberley; Kjaer, Susanne K.; Kliewer, Erich V.; Lemieux-Mellouki, Philippe; Markowitz, Lauri; Mboup, Aminata; Mesher, David; Niccolai, Linda; Oliphant, Jeannie; Pollock, Kevin G.; Soldan, Kate; Sonnenberg, Pam; Tabrizi, Sepehr N.; Tanton, Clare; Brisson, Marc; Department of Pediatrics, IU School of Medicine
    BACKGROUND: Human papillomavirus (HPV) vaccination programmes were first implemented in several countries worldwide in 2007. We did a systematic review and meta-analysis to assess the population-level consequences and herd effects after female HPV vaccination programmes, to verify whether or not the high efficacy reported in randomised controlled clinical trials are materialising in real-world situations. METHODS: We searched the Medline and Embase databases (between Jan 1, 2007 and Feb 28, 2014) and conference abstracts for time-trend studies that analysed changes, between the pre-vaccination and post-vaccination periods, in the incidence or prevalence of at least one HPV-related endpoint: HPV infection, anogenital warts, and high-grade cervical lesions. We used random-effects models to derive pooled relative risk (RR) estimates. We stratified all analyses by age and sex. We did subgroup analyses by comparing studies according to vaccine type, vaccination coverage, and years since implementation of the vaccination programme. We assessed heterogeneity across studies using I(2) and χ(2) statistics and we did trends analysis to examine the dose-response association between HPV vaccination coverage and each study effect measure. FINDINGS: We identified 20 eligible studies, which were all undertaken in nine high-income countries and represent more than 140 million person-years of follow-up. In countries with female vaccination coverage of at least 50%, HPV type 16 and 18 infections decreased significantly between the pre-vaccination and post-vaccination periods by 68% (RR 0·32, 95% CI 0·19-0·52) and anogenital warts decreased significantly by 61% (0·39, 0·22-0·71) in girls 13-19 years of age. Significant reductions were also recorded in HPV types 31, 33, and 45 in this age group of girls (RR 0·72, 95% CI 0·54-0·96), which suggests cross-protection. Additionally, significant reductions in anogenital warts were also reported in boys younger than 20 years of age (0·66 [95% CI 0·47-0·91]) and in women 20-39 years of age (0·68 [95% CI 0·51-0·89]), which suggests herd effects. In countries with female vaccination coverage lower than 50%, significant reductions in HPV types 16 and 18 infection (RR 0·50, 95% CI 0·34-0·74]) and in anogenital warts (0·86 [95% CI 0·79-0·94]) occurred in girls younger than 20 years of age, with no indication of cross-protection or herd effects. INTERPRETATION: Our results are promising for the long-term population-level effects of HPV vaccination programmes. However, continued monitoring is essential to identify any signals of potential waning efficacy or type-replacement. FUNDING: The Canadian Institutes of Health Research.
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    Risk perceptions, sexual attitudes, and sexual behavior after HPV vaccination in 11-12 year-old girls
    (Elsevier, 2015-07-31) Mullins, Tanya L. Kowalczyk; Widdice, Lea E.; Rosenthal, Susan L.; Zimet, Gregory D.; Kahn, Jessica A.; Department of Pediatrics, IU School of Medicine
    OBJECTIVES: Among 11-12 year-old girls who received the human papillomavirus (HPV) vaccine, we explored, over the subsequent 30 months: (1) trajectories of knowledge about HPV/HPV vaccines and vaccine-related risk perceptions; (2) whether knowledge and risk perceptions impacted sexual attitudes and sexual experience; (3) whether mothers, clinicians, and media influenced girls' risk perceptions, attitudes, and behavior. METHODS: Girls and mothers (n=25dyads) completed separate, semi-structured interviews within 2 days of, and 6, 18, and 30 months after, their first HPV vaccine dose. Knowledge, risk perceptions related to HPV and other sexually transmitted infections (STIs), and attitudes about sexual behaviors were assessed. Sexual experience was assessed at girls' 30 month interviews. Clinicians completed interviews at baseline. Transcribed interviews were analyzed using framework analysis. RESULTS: Girls' baseline knowledge was poor but often improved with time. Most girls (n=18) developed accurate risk perceptions about HPV but only half (n=12) developed accurate risk perceptions about other STIs by 30 months. The vast majority of girls thought that safer sex was still important, regardless of knowledge, risk perceptions, or sexual experience. Girls whose HPV knowledge was high at baseline or increased over time tended to articulate accurate risk perceptions; those who were able to articulate accurate risk perceptions tended to report not having initiated sexual activity. Girls whose mothers demonstrated higher knowledge and/or communication about HPV vaccination tended to articulate accurate risk perceptions, whereas clinicians and media exposure did not appear to influence risk perceptions. CONCLUSIONS: Higher knowledge about HPV vaccines among mothers and girls was linked with more accurate risk perceptions among girls. Clinicians may play an important role in providing education about HPV vaccines to mothers and girls.
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    Using the Theory of Planned behavior to identify correlates of HPV vaccination uptake among college students attending a rural university in Alabama
    (Elsevier, 2021-12) Shah, Sayyed Fawad Ali; Ginossar, Tamar; Bentley, Joshua M.; Zimet, Gregory; McGrail, J. Patrick; Pediatrics, School of Medicine
    INTRODUCTION: Humanpapillomavirus (HPV) has infected nearly 80 million people in the U.S., and is associated with most cervical cancer cases. Alabama ranks first in the country for cervical cancer mortality and third for incidence. Although the HPV vaccine can prevent HPV and reduce cancer rates, Alabama is well-below the national average for HPV vaccination. Using the Theory of Planned Behavior (TPB), this Alabama-based study aimed to examine college students' intentions to get the HPV vaccine; to examine the relationship between the relationship between religious beliefs and HPV vaccination uptake status among college students. METHODS: Students (n = 257) from a university in rural Alabama completed the survey. Multiple regression analysis, Mann-Whitney U tests, and moderation analysis were used to examine associations among the variables of interest. FINDINGS: Consistent with TPB, results showed that attitudes and subjective norms were significant predictors of intention to get vaccinated. Knowledge that both sexes can experience HPV-related health problems, that HPV can cause genital warts, and that the vaccine protects against HPV were each associated with higher attitude scores. The results indicated that the odds of getting at least one HPV shot were higher for females than for males for non-Caucasians than for Caucasians. Students who were not vaccinated were more likely to report that religion influenced their health beliefs. CONCLUSION: TPB was helpful in understanding HPV-related intentions. Communication and education efforts are needed to increase understanding of HPV illnesses and HPV vaccination benefits among peers, parents, and other loved ones of students. in the rural areas of Alabama.