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

Parental willingness to pay and preference for human papillomavirus vaccine for girls aged 9-14 in subsidy scenarios in Shanghai, China

Multiple studies have documented low human papillomavirus (HPV) vaccine uptake among Chinese girls. It remains crucial to determine the parental willingness to pay (WTP) HPV vaccine for girls. We conducted a cross-sectional study recruiting 3904 parents with girls aged 9-14 in Shanghai, China, employing an online questionnaire with a convenience sampling strategy. Parental WTP, both range of payment and estimated point value, were determined for themselves (or wives) and daughters. HPV vaccine uptake was 22.44% in mothers and 3.21% in daughters. Respondents favored WTP ≤ 1000 CNY/138 USD for themselves (or wives), whereas showed increasing WTP along with valency of HPV vaccine for daughters (2-valent: 68.62% ≤1000 CNY/138 USD; 4-valent: 56.27% 1001-2000 CNY/138-277 USD; 9-valent: 65.37% ≥2001 CNY/277 USD). Overall, respondents showed higher WTP for daughters (median 2000 CNY/277 USD; IQR 1000-3600 CNY/138-498 USD) than for themselves (2000 CNY/277 USD; 1000-3500 CNY/138-483 USD) or wives (2000 CNY/277 USD; 800-3000 CNY/110-414 USD) (each p < .05). Furthermore, parental WTP was higher for international vaccine and 9-valent vaccine (each p < 0.05). Between two assumed government subsidy scenarios, parental preference for 9-valent vaccine remained consistently high for daughters (approximately 24% in each scenario), whereas preference for themselves (or wives) was sensitive to payment change between the subsidy scenarios. Using a discrete choice experiment, we found domestic vaccine was commonly preferred; however, certain sociodemographic groups preferred multivalent HPV vaccines. In conclusion, the valency of HPV vaccine may influence parental decision-making for daughters, in addition to vaccine price. Our findings would facilitate tailoring the HPV immunization program in China.

Return on Investment (ROI) of Three Vaccination Programmes in Italy: HPV at 12 Years, Herpes Zoster in Adults, and Influenza in the Elderly

The calculation of the return on investment (ROI) allows the estimation of the opportunity cost of a series of interventions and can therefore help to make allocative choices. The objective of this study is to estimate the ROI of three vaccinations (HPV for adolescents, HZ for adults, and influenza for the elderly) in the Italian context, considering the impact of increasing vaccination coverage based on target objectives of the National Immunization Plan (PNPV) 2017-2019 and accounting for different eligibility criteria of each vaccination. Three separate static cohort models were constructed, including the eligible population for these vaccinations on the basis of the PNPV 2017-2019 and following this population until death (lifetime horizon) or until vaccination waning. Each model compares the level of investment at current vaccine coverage rates (current VCRs scenario) with that of optimal NIP target VCRs with a non-vaccination scenario. The ROI for HPV vaccination was the highest among the programs compared and was always above 1 (range: 1.4-3.58), while lower values were estimated for influenza vaccination in the elderly (range 0.48-0.53) and for vaccination against HZ (range: 0.09-0.27). Our analysis showed that a significant proportion of savings generated by vaccination programs occurred outside the NHS perspective and might often not be estimated with other forms of economic evaluation.

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.

Impact of a human papillomavirus vaccination programme within organized cervical cancer screening: cohort study

BACKGROUND

We assessed the effectiveness of an HPV vaccination programme in lowering cervical abnormality risk, and conferring herd protection.

METHODS

Retrospective cohort study using linked screening and vaccination administrative health data of the general population of Ancona Province, Italy. We included all female residents born in 1990-1993, eligible for catch-up HPV vaccination up to age 25y, and adhering to organised screening in 2015-2020 (n=4665). Cervical abnormalities rates were compared between: vaccinated and unvaccinated women, and cohorts with high and low vaccination uptake. Analyses were adjusted for age, country of birth, screening tests number, laboratory, and municipality average income. Main outcomes were ASC-US+ or LSIL+ Pap smears, and CIN1+ or CIN2+ histology.

RESULTS

Mean screening age was 26.6{plus minus}1.5 years, and 1,118 screened women (24.0%) were vaccinated (mean vaccination age 19.2{plus minus}1.5 years). The diagnosed cervical abnormalities were: 107 LSIL+ (2.3%), 70 CIN1+ (1.5%), and 35 CIN2+ (0.8%). The adjusted odds ratios of LSIL+, CIN1+ and CIN2+ among vaccinated vs unvaccinated women were, respectively: 0.55 (95% confidence interval 0.33-0.91), 0.43 (0.22-0.86), and 0.31 (0.11-0.91). Among the unvaccinated, those in the highest-uptake (45.3%) 1993 cohort, versus the last pre-vaccination 1990 cohort, showed AORs of LSIL+ and CIN1+ of 0.23 (0.10-0.50), and 0.22 (0.07-0.69), respectively.

CONCLUSIONS

In the first evaluation from Central Italy, catch-up HPV vaccination considerably reduced the risk of all cervical abnormalities diagnosed within organized screening, and conferred an elevated degree of herd protection among unvaccinated women.

IMPACT

The high protection conferred by HPV vaccination suggests the need to update cervical screening.