The effectiveness of vaccination to prevent the papillomavirus infection: a systematic review and meta-analysis

HPV vaccine introduction in the Americas: a decade of progress and lessons learned

INTRODUCTION

Human papillomavirus (HPV) is an important public health concern due to its causative role in many cancers, especially cervical cancer, and other conditions that lead to serious health consequences in both men and women. In Latin America and the Caribbean, nearly 60,000 new cases of cervical cancer and another 7,000 HPV-associated cancers are diagnosed annually.

AREAS COVERED

HPV vaccination combined with comprehensive cervical cancer control programmingis paving the way for eliminating cervical cancer as a major public health problem and drastically reducing other HPV-associated diseases. To date, 44 countries and territories in the Americas have introduced HPV vaccines as part of their national immunization programs and cervical cancer control strategies. Early lessons from HPV vaccine introduction suggest that transparent and credible evidence-based decision-making, information, education and communication about HPV and cervical cancer, coordination with existing cervical cancer control initiatives, and precise planning for ensuring effective uptake of the vaccine in target groups are all critical elements of success.

EXPERT OPINION

There is an urgent need for strategies to increase HPV vaccine coverage, and as the integrated control programs evolve and other HPV-associated disease becomes important for public health, there will be a need for continued program and policy evaluation.

Impact of industry sponsorship on the quality of systematic reviews of vaccines: a cross-sectional analysis of studies published from 2016 to 2019

BACKGROUND

Systematic reviews (SRs) provide the highest level of evidence and inform evidence-based decision making in health care. Earlier studies found association with industry to be negatively associated with methodological quality of SRs. However, this has not been investigated in SRs on vaccines.

METHODS

We performed a systematic literature search using MEDLINE and EMBASE in March 2020. The results were restricted to those published between 2016 and 2019 with no language restrictions. Study characteristics were extracted by one person and checked by an experienced reviewer. The methodological quality of the SRs was assessed with the AMSTAR 2 tool by multiple reviewers after a calibration exercise was performed. A summary score for each SR was calculated. The Mann-Whitney U test and Fisher's exact test were performed to compare both groups.

RESULTS

Out of 185 SRs that met all inclusion criteria, 27 SRs were industry funded. Those were matched with 30 non-industry funded SRs resulting in a total sample size of 57. The mean AMSTAR 2 summary score across all SRs was 0.49. Overall, the median AMSTAR 2 summary score was higher for the non-industry funded SRs than for the industry-funded SRs (0.62 vs. 0.36; p < .00001). Lower ratings for industry funded SRs were consistent across all but one AMSTAR 2 item, though significantly lower only for three specific items.

CONCLUSION

The methodological quality of SRs in vaccination is comparable to SRs in other fields, while it is still suboptimal. We are not able to provide a satisfactory explanation why industry funded SRs had a lower methodological quality than non-industry funded SRs over recent years. Industry funding is an important indicator of methodological quality for vaccine SRs and should be carefully considered when appraising SR quality.

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

BACKGROUND

Recommendations 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.

METHODS

After 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.

RESULTS

The 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).

CONCLUSION

HPV 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.

Strong reduction in prevalence of HPV16/18 and closely related HPV types in sexually active adolescent women following the introduction of HPV vaccination in Argentina

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HPV16/18 decreased by >93% in vaccinated sexually active Argentine girls.

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Detected reduction of HPV31 and 45 would add to the success of immunization.

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No genotype replacement was observed.

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First HPV vaccination monitoring data reported from a Latin American country.

Human Papillomavirus Vaccination and Physical and Mental Health Complaints Among Female Students in Secondary Education Institutions in Denmark

BACKGROUND

Previous studies have not explored the effect of HPV vaccination on health status at a longer time interval. Similarly, self-reported physical and mental health in recipients of the HPV vaccine has not been studied.

OBJECTIVE

To evaluate whether HPV vaccination was associated with physical and mental health complaints among girls in secondary education institutions.

DESIGN

Prospective cohort study.

PARTICIPANTS

This study used data from girls aged 15-20 years who participated in the Danish National Youth Study (DNYS) 2014. Data on HPV vaccination was retrieved from the Danish Vaccination Register.

MAIN MEASURES

Participants were asked whether they had experienced headaches, stomachache, neck pain, menstrual cramps, sore throat, sadness, irritation, nervousness and sleep problems in the past 6 months.

KEY RESULTS

Of 41,333 girls, 39,145 (94.7%) received at least one dose of HPV vaccine. The most prevalent health complaint among the vaccinated and not vaccinated females was "been irritable" (88.2% and 88.4%, respectively). The lowest proportion of health complaints was stomachache (49.6% in vaccinated and in 50.4% in unvaccinated girls). Regression model, adjusted for socio-demographic characteristics and health behavior, showed that HPV vaccination was associated with a lower likelihood of reporting sore throat (odd ratio [OR] 0.86, 95% confidence interval [CI] 0.78-0.95) and being sad (OR 0.86, 95%CI 0.76-0.97). Similar results were observed when HPV vaccination status was analyzed according to the number of doses received.

CONCLUSION

We conclude that HPV vaccination was not associated with physical and mental health complaints among girls in secondary education institutions in Denmark after a median of 5.3 years since HPV vaccination.