Impact of HPV vaccination: health gains in the Italian female population

HPV Vaccination during the COVID-19 Pandemic in Italy: Opportunity Loss or Incremental Cost

Objectives: Italy was the first European country to introduce universal vaccination of adolescents, for both males and females, against Human Papilloma Virus (HPV) starting in 2017 with the NIP 2017–2019′s release. However, vaccine coverage rates (VCRs) among adolescents have shown a precarious take-off since the NIP’s release, and this situation worsened due to the impact of the COVID-19 pandemic in 2020. The aim of this work is to estimate the epidemiological and economic impact of drops in VCRs due to the pandemic on those generations that missed the vaccination appointment and to discuss alternative scenarios in light of the national data. Methods: Through an analysis of the official ministerial HPV vaccination reports, a model was developed to estimate the number of 12-year-old males and females who were not vaccinated against HPV during the period 2017–2021. Based on previously published models that estimate the incidence and the economic impact of HPV-related diseases in Italy, a new model was developed to estimate the impact of the aggregated HPV VCRs achieved in Italy between 2017 and 2021. Results: Overall, in 2021, 723,375 girls and 1,011,906 boys born between 2005 and 2009 were not vaccinated against HPV in Italy (42% and 52% of these cohorts, respectively). As compared with the 95% target provided by the Italian NIP, between 505,000 and 634,000 girls will not be protected against a large number of HPV-related diseases. For boys, the number of the unvaccinated population compared to the applicable target is over 615,000 in the ‘best case scenario’ and over 749,000 in the ‘worst case scenario’. Overall, between 1.1 and 1.3 million young adolescents born between 2005 and 2009 will not be protected against HPV-related diseases over their lifetime with expected lifetime costs of non-vaccination that will be over EUR 905 million. If the 95% optimal VCRs were achieved, the model estimates a cost reduction equal to EUR 529 million, the net of the costs incurred to implement the vaccination program. Conclusion: Suboptimal vaccination coverage represents a missed opportunity, not only because of the increased burden of HPV-related diseases, but also in terms of economic loss. Thus, reaching national HPV immunization goals is a public health priority.

Human papillomavirus in Italy: retrospective cohort analysis and preliminary vaccination effect from real-world data

INTRODUCTION

The objective of this study was to estimate the lifetime risk of hospitalization associated with all major human papillomavirus (HPV)-related diseases in Italy. Moreover, a preliminary vaccination effect was also performed.

METHODS

A retrospective, nonrandomized, observational study was developed based on patients hospitalized between 2006 and 2018 in Italy. All hospitalizations were identified through administrative archives, according to the International Classification of Diseases (ICD-9 CM). Information related to the hospital discharges of all accredited public and private hospitals, both for ordinary and day care regimes, was taken into account. We included hospitalizations related to resident patients presenting one of the ICD-9-CM codes as primary or secondary diagnosis: genital warts (GW); 'cervical intraepithelial neoplasia (CIN)' (067.32-067.33); 'condyloma acuminatum' (078.11); 'anal cancers' (AC) (154.2-154.8); oropharyngeal cancers (OC): 'oropharyngeal cancer'(146.0-146.9) and 'head, face and neck cancers' (171.0); genital cancers (GC): 'penis cancer' (187.1-187.9) and 'cervical cancer' (180.0-180.9). Data were stratified by birth year and divided into two groups: (a) cohort born before 1996 (not vaccinable) and (b) cohort born after 1997 (vaccinable-first cohort that could be vaccinated at the beginning of immunization schedule in girls since 2008 in Italy). Disease-specific hospitalization risks for both groups were estimated by sex, year and age.

RESULTS

Epidemiological data demonstrate that the peak hospitalization risk occurred at 24-26 years of age for GW (both male and female); 33-41 and 47-54 years for AC males and females, respectively; 53-59 and 52-58 years for OC males and females, respectively; and 54-60 and 39-46 years for GC males and females, respectively. Focusing on GW and GC, vaccinable females demonstrate a significant reduction in hospitalization risks (- 54% on average) compared to nonvaccinable females until 21 years of age (maximum follow-up available for girls born after 1997). Comparing the same birth cohort of males, no differences in hospitalization risk were found.

CONCLUSIONS

These results support the importance of primary prevention strategies in Italy and suggest that increased VCRs and time of observation (genital cancers for which vaccination is highly effective, have a latency of some decades) will provide useful information for decision-makers.

Computational modeling of human papillomavirus with impulsive vaccination

In this study, a new SIVS epidemic model for human papillomavirus (HPV) is proposed. The global dynamics of the proposed model are analyzed under pulse vaccination for the susceptible unvaccinated females and males. The threshold value for the disease-free periodic solution is obtained using the comparison theory for ordinary differential equations. It is demonstrated that the disease-free periodic solution is globally stable if the reproduction number is less than unity under some defined parameters. Moreover, we found the critical value of the pulse vaccination for susceptible females needed to control the HPV. The uniform persistence of the disease for some parameter values is also analyzed. The numerical simulations conducted agreed with the theoretical findings. It is found out using numerical simulation that the pulse vaccination has a good impact on reducing the disease.

Burden of Disease of Human Papillomavirus (HPV): Hospitalizations in the Marche and Veneto Regions. An observational study

BACKGROUND AND OBJECTIVES

HPV (human papillomavirus) is the virus most often responsible for sexually transmitted infections. The burden of HPV-related diseases on hospital resources represents a major public health problem. The aim of this study was to assess the economic burden of HPV-related diseases (anal cancer, genital cancer, genital warts, oropharyngeal cancer) on hospital resources in two Italian regions.

METHODS

A retrospective, non-randomized, observational study was developed in the Marche and Veneto Regions, based on patients receiving hospitalization between 2008 and 2011. All hospitalizations were identified through administrative archives, according to the International Classification of Diseases (ICD-9 CM) to which a defined tariff was assigned.

RESULTS

We identified 5299 hospitalized patients in Veneto and 1735 in the Marche Region. The mean annual hospitalization rate was 49.44 per 100,000 individuals in Veneto and 48.41 in Marche. The total mean annual cost attributable to HPV-related diseases was €5.78 (SD 0.80) million in Veneto and €2.24 (SD 0.17) million in Marche. Costs associated with genital cancer amounted to €1.61 million in Veneto and €1.06 million in Marche (28% and 47% of the total mean annual cost, respectively). Oropharyngeal cancer accounted for 36% in Veneto (€2.08 million) and 28% in Marche (€632,645). Hospitalization costs related to anal cancer were €882,567 in Veneto and €377,719 in Marche; genital warts accounted for €1.19 million in Veneto and €171,406 in Marche. Finally, the mean cost per patient was €4364 in Veneto and €5176 in Marche.

CONCLUSIONS

The present work estimated the cost of HPV-related diseases for hospitalized patients in two Italian regions. The considerable estimated annual economic burden is a powerful driver for the governance of the public health sector.