ABSTRACT
The aim of the present study is to evaluate the 2023/24 and 2024/25 influenza vaccination campaigns in Liguria (Italy), specifically analyzing how the transition toward a proximity-based model impacted vaccine appropriateness across different age groups (60–64 y, ≥65 y) and providers. Data regarding seasonal influenza vaccine administrations were extracted from the official Local Health Units (LHUs) immunization registries, which aggregate immunization records from different providers [LHUs, General Practitioners (GPs), pediatricians and community pharmacies]. To evaluate prescriptive appropriklateness, administered vaccines were cross-referenced with national guidelines based on the patient’s age. A 6% overall decrease in coverage rates between the two seasons was recorded while the provider landscape shifted significantly. Unfortunately, while enhancing proximity (General Practitioners and pharmacies), this evolution introduced wide variability in prescriptive appropriateness. Our analysis reveals a persistent mismatch between national recommendations and real-world clinical practice and only 65% (2023/24 season) and 73% (2024/25 season) among ≥65 y individuals received enhanced vaccines. Strengthening clinical governance and targeted professional training for pharmacists and GPs is essential to ensure that the convenience of proximity-based vaccination does not compromise clinical efficacy through the use of sub-optimal vaccine platforms for high-risk cohorts.
KEYWORDS: Influenza vaccines, appropriateness, adjuvanted vaccines, enhanced influenza vaccines, coverage rate, seasonal influenza vaccines providers
Introduction
Influenza is a vaccine-preventable respiratory infection that remains a primary cause of morbidity and mortality worldwide, spreading mainly via respiratory droplets and direct contact.1,2 In the European Union and European Economic Area (EU/EEA), season-al influenza causes up to 50 million symptomatic cases annually, with an estimated 15,000–70,000 deaths, alongside a substantial socioeconomic burden.3,4
In Italy, seasonal influenza poses a substantial public health challenge,5,6 with an average annual excess mortality rate of 11.6–41.2 per 100,000 inhabitants7; most influenza-related deaths are concentrated among the elderly, who are particularly vulnerable due to immunosenescence and comorbidities.6,7
Annual vaccination is the primary and most effective intervention to mitigate influenza severity, reduce hospitalizations, and prevent mortality, while also limiting community transmission.8,9 A coverage rate above 75% is recommended by WHO and Italian National Vaccination Plan; the seasonal influenza strategy foresee the recommended influenza vaccination coverage targets are set at a minimum achievable level of 75% and an optimal level of 95% for adults aged ≥ 65 y.10 The use of the appropriate vaccine is another key factor in ensuring a high impact of the vaccination campaign. Given that enhanced vaccines, including adjuvanted (ADJ) and high‑dose (HD) formulations, have demonstrated significantly greater effectiveness in older adults, vaccination strategies should prioritize ensuring that the most suitable vaccine is administered to the individuals most likely to benefit from it.11–13
To this end, the Italian Ministry of Health issues an annual Ministerial Circular integrating epidemiological and virological surveillance with vaccine composition recommendations, identifying priority groups such as the elderly and individuals with comorbidities.10 At the sub-national level, regional health authorities translate these national directives into tailored, operational local policies. In Liguria, the Regional Vaccines Committee is responsible for contextualizing these strategies: its guidelines define the appropriate vaccine products for different risk groups, thereby maximizing the impact of the regional immunization program. To ensure the success of the clinical indications and strive toward national coverage targets, Liguria region has adopted a robust multi-channel delivery model, integrating the capillary network of Local Health Units’ (LHUs) prevention departments, General Practitioners (GPs) and Pediatricians (PLS) with the expanding role of community pharmacies.14
Consequently, the present study is aimed at analyzing coverage gaps and promoting the appropriate use of vaccine focusing on coverage trends and prescriptive appropriateness across providers in older adults (≥60 y), in order to inform organizational strategies that minimize coverage gaps and promote an appropriate use of vaccine.
Materials and methods
Seasonal influenza vaccine campaign
In Italy, the main influenza vaccines authorized for seasonal campaigns include tri-valent egg-based (TIVe), cell-based (TIVc), MF59-adjuvanted (aTIV), and high-dose (hdTIV) formulations, plus the Live Attenuated Influenza Vaccine (LAIV)10,11,13; until the 2023/24 season these were quadrivalent.
Each year, the campaign runs from October to January, peaking in November–December and prioritizing adults ≥65 y, individuals aged 6 months–65 y with chronic conditions, extended-care residents, close contacts of high-risk individuals, pregnant women, healthcare staff, and animal-exposed workers.
The 2023/24 and 2024/25 regional influenza vaccination campaigns followed Health Ministry recommendations, coordinated by the Regional Health Authority, A.Li.Sa., in collaboration with the Regional Vaccination Commission and the LHUs. To ensure broad accessibility, vaccination was provided free of charge to eligible groups through a multi-channel delivery network, including LHUs Prevention Departments, general practitioners (GPs), and community pharmacies. This organizational structure was designed to enhance coverage through an inclusive and accessible service model.14
Within this framework, particular emphasis was placed on maximizing appropriateness for older adults, driven by growing evidence on the superior performance of enhanced formulations.11 In our work, vaccine appropriateness was determined by cross-referencing the age of the recipient with the vaccine-specific indications reported in Table 1, which reflects the Ministerial Circular for each season10 as translated into regional guidance by the Liguria Regional Vaccines Committee. Administrations were classified as “Recommended” (R) when the vaccine type matched the age-specific first-choice indication and “Administrable” (A) when the vaccine was licensed but not preferentially indicated for that age group. This classification differed between 2023/24 and 2024/25 because the Regional Vaccination Commission lowered the age threshold for enhanced-vaccine recommendation from 65 to 60 y in season 2024/25 on the basis of the available evidence.15
Table 1.
National guidelines for 2023/2024 and 2024/2025 seasonal influenza immunization campaigns by vaccine type and target age group.
| Target (age) | Influenza season 2023/2024 |
Influenza season 2024/2025 |
||||
|---|---|---|---|---|---|---|
| aQIV# | hdQIV# | QIVe, QIVc# | aTIV | hdTIV | TIVe, TIVc | |
| Individuals ≥ 65 y | R | R | A | R | R | A |
| Individuals 60–64 y | A | A | A | A(R*) | A | A |
A = Administrable; R = Recommended. TIVe = Trivalent egg-based influenza vaccines; TIVc = Trivalent influenza cell vaccines; aTIV = Trivalent adjuvanted influenza vaccines; hd-TIV = Trivalent high-dose influenza vaccines. QIVe = Quadrivalent egg-based influenza vaccines; QIVc = Quadrivalent influenza cell vaccines; aQIV = Quarivalent adjuvanted influenza vaccines; hd-QIV = Quarivalent high-dose influenza vaccines.
#During the 2023/2024 season, quadrivalent formulations were available.
*The Regional Vaccines Committee recommended the aTIV vaccine for individuals aged 60–64 y during the 2024/2025 influenza season.
Study setting and variables
As of January 1, 2024, the Liguria Region (Italy) had 1,507,636 inhabitants, organized into five Local Health Units (LHUs) with catchment populations of 208,729 (LHU1), 267,366 (LHU2), 681,353 (LHU3), 135,316 (LHU4), and 214,872 (LHU5).16 Individuals aged ≥65 represented 29% of the population.17
The variables analyzed included age categories eligible for vaccination and the recommended vaccine type per group. Vaccine administration was defined as ‘inappropriate administration’ if the vaccine type used was not aligned with the explicit recommendations (indicated by ‘R’ in Table 1) or was contraindicated for that specific population group, according to national guidelines.
Data source and analysis
Data regarding seasonal influenza vaccine administrations for the 2023/24 and 2024/25 campaigns were retrieved from the official LHU immunization registries, which aggregate records from all authorized providers (LHU Prevention Departments, GPs, pediatricians, community pharmacies); the final dataset was extracted on August 31, 2025. Historical data back to 2021 were sourced from the Regional Vaccine Committee archives.
The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee, Genoa (Italy) 99/2025 - id 14,437 date 18 march 2025).
Written informed consent to vaccination was obtained and data of vaccination was used according the Ligurian Regional Law n. 17/2016. All data were analyzed in anonymized and aggregated form to ensure privacy compliance.
Vaccine uptake was stratified by age cohort, product type, and provider category, with the primary objective of evaluating administration appropriateness by cross-referencing administered vaccines with national guidelines and regional strategic segmentation.
A retrospective descriptive analysis was performed to characterize the vaccination campaign’s results, with categorical variables summarized using absolute frequencies and percentages. A comparative analysis was subsequently conducted to evaluate performance and appropriateness across different delivery settings, age class and influenza seasons. The statistical significance of the association between vaccine product types and administration appropriateness was assessed using Pearson’s chi-square (χ2) test. All statistical analyses were conducted using Stata, version 18.0 (StataCorp LP, College Station, TX, USA).
To further characterize provider-related variability in prescriptive appropriateness among adults aged ≥65 y, supplementary analyses were performed on provider- and season-specific aggregated counts (GPs, community pharmacies, and LHU Prevention Departments; 2023/24 and 2024/25 seasons). A multivariable generalized linear model with a binomial distribution and a logit link function, fitted on provider × season aggregated counts, was used to estimate adjusted odds ratios and to formally test whether the season-to-season change in appropriateness differed across providers. A p-value < .05 was considered statistically significant for all analyses.
Results
Over the years, the landscape of seasonal influenza vaccination in Liguria has undergone significant structural shifts. As shown in Figure 1, coverage across all pediatric and adult cohorts peaked in the 2020/21 season, coinciding with the COVID-19 pandemic and Regional Decree 885/2020, which extended free vaccination to children (6 months–6 y) and adults aged 60–64. That season, total administration reached approximately 475,000 doses, with over-65 coverage peaking at 68%. Since then, overall volumes have declined: total administered doses decreased from 337,951 in 2023/24 to 314,718 in 2024/25 (−6.9%, −23,000 doses). Coverage among the over-65 population settled at a suboptimal 48.7% in 2024/25, well below the WHO’s 75% minimum target.
Figure 1.
Five-year historical trends of influenza vaccination coverage rates by age group and provider contributions from 2020/21 season.
In the same period, the organizational structure of the campaigns has evolved significantly with the diversification of vaccine providers (Figure 2). A key driver of the evolution was the introduction of Community Pharmacies as providers in the 2022/23 season, whose contribution has since demonstrated a steady upward trajectory. Conversely, administrations within LHU/Hospital settings saw a sharp decline, while General Practitioners (GPs) and Pediatricians maintained their role as primary, high-volume providers.
Figure 2.
Trends in seasonal influenza vaccine uptake in the Liguria region, stratified by provider category and age group.
In particular, focusing on the two most recent influenza seasons, a significant shift in the provider mix was observed in Liguria. During the 2023/24 season GPs administered 66.6% of all vaccinations, followed by the Prevention Department (23.2%) and Community Pharmacies (10.2%). By 2024/25, the share delivered by GPs had increased to 69.5%, while Community Pharmacies expanded their share to 15.4%. In contrast, the Prevention Department’s share declined to 15.1%. A similar trend emerged within the older adult population (≥65 y), since GPs vaccinated 71.9% and 78.3% of these recipients in the 2023/24 and 2024/25 seasons, respectively. Concurrently, the contribution of Community Pharmacies grew from 11.2% to 17.0%, while the share administered by Prevention Departments fell sharply from 16.9% to 4.7%.
Despite changes in the provider landscape, the demographic profile of recipients remained consistent over time, with one notable exception. In Community Pharmacies, adults ≥65 y represented 76.8% of vaccinees in 2023/24 and 74.7% in 2024/25; individuals aged 60–64 y accounted for 9.9% and 10.1%, respectively, while the under-60 cohort represented 13.3% and 15.2%. GPs showed a nearly identical pattern: in 2023/24, 76.2% of doses went to over-65s, 8.5% to 60–64-y-olds, and 15.3% to under-60s; in 2024/25 the distribution was 76.4% of doses to over-65s, 8.1% to 60–64-y-olds, and 15.5% to under-60s. In Prevention Departments, however, a marked shift occurred, with adults ≥65 y that fell from 51.5% of vaccinees in 2023/24 to 21.2% the following year.
During 2023/24 season, among individuals aged ≥65 y, 34.6% were inappropriately administered standard-dose formulations (QIVe and QIVc) instead of recommended enhanced vaccines (aQIV or HD-QIV). Coverage with enhanced vaccines reached 72.6% among general practitioners (GPs), compared with 49.7% in Prevention Departments and 42.7% in community pharmacies.
In the 2024/25 season, overall prescribing appropriateness in the ≥65 y cohort increased to 73.3%, largely driven by Prevention Departments, where more than 90% of older adults received enhanced vaccines. In contrast, only modest improvements in prescribing appropriateness were observed among GPs and community pharmacies.
In the 60–64 y cohort, the introduction of the recommendation to administer enhanced influenza vaccines during the 2024/25 season was implemented in 43.3% of eligible individuals overall. Adherence to the recommendation was 42.3% among general practitioners (GPs), 43.7% in community pharmacies, and 50.5% in Prevention Departments (Table 2).
Table 2.
Individuals ≥ 60 y who received the appropriate enhanced vaccine broken down age class and influenza season.
| 60–64 y |
65 y and over |
||||
|---|---|---|---|---|---|
| 2023/24 season (n.) | 2024/25 season (n.) | 2023/24 season (n.) | 2024/25 season (n.) | ||
| Administered doses | GPs | 19,207 | 17,601 | 171,355 | 167,122 |
| Pharm | 3,414 | 4,900 | 26,616 | 36,215 | |
| LHUs | 5,419 | 2,305 | 40,320 | 10,106 | |
| Tot | 28,040 | 24,806 | 238,291 | 213,443 | |
|
Enhanced vaccine administered doses |
GPs | 1,545 (8.0%) | 7,438 (42.3%) | 124,386 (72.6%) | 124,802 (74.7%) |
| Pharm | 141 (4.1%) | 2,139 (43.7%) | 11,370 (42.7%) | 22,471 (62.0%) | |
| LHUs | 331 (6.1%) | 1,163 (50.5%) | 20,022 (49.7%) | 9,166 (90.7%) | |
| Tot | 2,017 (7.2%) | 10,740 (43.3%) | 155,778 (65.4%) | 156,439 (73.3%) | |
The analysis of prescriptive appropriateness across vaccine providers, evaluated via a multivariable GLM revealed statistically significant disparities. The model demonstrated a highly significant provider × times season interaction (p < .001), indicating that the season-to-season change in appropriateness differed substantially across delivery channels rather than following a uniform trend (Tables S1-S2). GPs maintained a substantial and stable advantage over pharmacies across both seasons, whereas pharmacies consistently exhibited the lowest estimated probability of appropriate vaccination.
To quantify the public health impact of inappropriate vaccine administration, we applied the vaccine effectiveness (VE) estimates from Domnich et al.,11 derived from a test-negative case-control study in Liguria during the 2023/24 season, the same population under study. In that publication, absolute VE of standard-dose formulations (QIVe) against influenza A-related hospitalization was 2%, vs. an adjusted VE of 56–58% for enhanced formulations (adjuvanted MF59-QIV and high-dose QIV-HD). Applying this framework, assuming unchanged vaccination coverage, the use of standard influenza vaccines would have failed to protect more than 45,700 individuals aged ≥65 y out of 238,300 vaccinees during the 2023/24 season. In contrast, the introduction of a recommendation to use enhanced influenza vaccines in individuals aged 60–64 y, together with optimal adherence to the recommendation among those aged ≥ 65 y, would have protected nearly 40,000 additional individuals during the 2024/25 season, 31,700 and 7,600 in ≥65 and 60–64 y cohorts, respectively.
Discussion
In Italy, seasonal influenza vaccination campaigns have historically evolved through a progressive expansion of the target population and the introduction of diversified vaccine platforms to optimize health outcomes, improve quality of life, generate economic benefits, and ensure comprehensive protection across all age groups.18 The primary challenge in modern public health is no longer merely ensuring vaccine availability, but also optimizing its administration to maximize clinical efficacy and socioeconomic value.18–20
Missed-opportunity research has identified psychological, contextual, sociodemographic, and communication gaps underlying suboptimal uptake.21 The evolution of Liguria’s vaccination landscape reflects a structural transition toward a proximity-based model17; however, our findings show that increased accessibility does not automatically translate into higher coverage or improved clinical appropriateness.
The introduction of community pharmacies as active providers in the 2022/23 season has redistributed the administration workload, with pharmacies accounting for more than 15% of total regional doses in the 2024/25 season. This shift aligns with the “Pharmacy of Services” framework, positioning these facilities as highly accessible health hubs. International literature suggests that integrating pharmacies into immunization strategies can increase influenza vaccination rates.22,23 However, our findings indicate that this potential has not yet been fully realized in Liguria.
Analysis of influenza vaccine usage data over the past five seasons reveals that an expansion in the number of providers did not translate into higher vaccination coverage. The downward trend observed in our region aligns with patterns across other Italian territories, which have documented a decrease of at least 4% to 5% from the 2022/23 season to the present.22 This phenomenon is likely driven by a confluence of factors, including public acceptance, provider participation, and campaign implementation strategies. While some studies attribute this decline to post-pandemic vaccine fatigue and a diminished risk perception stemming from widespread preventive measures,24 others suggest that spatiotemporal variations in vaccine uptake among the Italian elderly may be partially driven by increased general practitioner workloads resulting from a declining physician workforce.25 The decline in LHU-based vaccinations suggests that while pharmacies offer superior accessibility, they may be currently absorbing existing demand rather than generating a substantial “catch-up” effect among the unvaccinated population, since coverage rates for the 2023/24 and 2024/25 seasons (54.5% and 52.5%, respectively) remain significantly below the 75% minimum and 95% optimal targets set by national health authorities.
However, this finding is not unexpected, since vaccine uptake in many European countries remains suboptimal and vaccine strategies are not harmonized.26,27
Beyond coverage, a critical challenge concerns the appropriateness of vaccines administered in these new settings. “Precision vaccination” requires aligning the vaccine’s technological platform with the recipient’s immunological needs based on age and risk factors19,23–28; due to immunosenescence, standard-dose vaccines often fail to elicit an optimal response in older adults.11 Accordingly, Ministerial Circulars and regional guidelines strongly recommend enhanced vaccines – MF59-adjuvanted (aQIV) and High-Dose (hd-QIV) for those aged ≥ 65 y.10 Unfortunately, our analysis reveals a persistent mismatch between these recommendations and real-world practice in Liguria, where only 65.4% and 73.3% of vaccines aged ≥65 y received the recommended formulations in 2023/24 and 2024/25, respectively – consistent with regional variability in enhanced-vaccine optimization across Italy13 and with persistently suboptimal elderly coverage in several EU member states.29,30 Prescribing appropriateness shows substantial variation across healthcare providers, as well as differing growth trends following the strengthening and revision of the recommendations.
Taken together, these findings paint a consistent picture: while the structural expansion of the vaccination network improved logistical accessibility, significant clinical gaps persisted across consecutive campaigns, with the newly expanded 60–64 age cohort.
While the use of enhanced vaccines is technically correct under regulatory standards, the primary challenge remains the “off-target” use of standard-dose products in the elderly.31,32 Given the markedly higher effectiveness of enhanced vaccines vs. standard-dose vaccines against influenza A-related hospitalization in this population,11 this inappropriate allocation caused a considerable loss of protection: cumulatively across both seasons, an estimated 85,000 vaccine-eligible individuals failed to achieve the protection that full guideline adherence would have conferred, highlighting the need for targeted interventions to improve adherence to age-specific recommendations.
It should be noted that enhanced influenza vaccines have an established safety record which should be emphasized when discussing the benefits of influenza vaccination with older adults. In the Liguria Region (Italy), where the present study was conducted, a three-season Enhanced Passive Safety Surveillance (EPSS) program confirmed the favorable safety profile of these vaccines.33,34 The observed variability in enhanced-vaccine use across providers may therefore reflect differences in vaccine stocking practices, prescribing patterns, and awareness of age-specific recommendations across settings, rather than patient-driven avoidance related to concerns about reactogenicity.
Although the shift from institutional LHU-based vaccination services to public–private partnership models may enhance equity of access, it requires strengthened governance to maintain quality and prescribing appropriateness in line with specialized public health department standards, particularly for enhanced influenza vaccine formulations in older adults, where variability in provider adherence is greatest.
In Liguria, where 29% of the population is aged 65 and older and pharmacies are increasingly primary access points amid reduced GP availability, this reliance raises questions about heterogeneity in protection quality across delivery channels. The only comparable Italian dataset, from the Local Health Unit of Catania,30 reported an appropriateness rate of 78.8% in the ≥65 cohort in 2023/24, rising to 96.1% in 2024/25 – substantially higher than Liguria’s. While organizational differences limit direct comparison, the divergence may reflect Liguria’s more rapid multi-channel expansion relative to more institutionally concentrated models.
Nevertheless, the improvement observed between seasons demonstrates that rapid operational progress is achievable. To sustain this momentum, governance mechanisms must bridge the gap between regional procurement policies and clinical delivery through a multi-faceted approach. Concrete governance mechanisms could be implemented to improve both influenza vaccination uptake and the appropriateness of vaccine selection by means several tasks. Interventions shown to improve uptake included operational planning and clinical improvement systems, provider education and reminders.35 First, point-of-care electronic decision-support tools could be integrated into the prescribing, dispensing, and vaccination software used by GPs, pharmacists, and public health services; such systems could generate real-time alerts when a selected vaccine differs from age-specific recommendations and document the clinical rationale for the deviation, addressing the complexity of an Italian framework where annual Ministry guidelines specify vaccine options by age and risk group while Regions determine procured products. Second, strategies should prioritize continuous training for pharmacists and GPs to strengthen technical knowledge and patient counseling,36 alongside public engagement to disseminate accurate information on age-specific vaccine benefits. In fact, evidence from Italy suggests that targeted educational programme can increase GPs’ confidence in discussing influenza vaccination and increase their willingness to recommend enhanced vaccines to older adults.37 Structured and mandatory continuing professional education could be provided to GPs and pharmacists before the beginning of each influenza season; training should focus on the interpretation of the annual national and regional recommendations, the indications for enhanced vaccines in older adults, vaccine effectiveness and safety, and communication strategies for addressing vaccine hesitancy.
Finally, periodic audit-and-feedback systems should be established at the provider and local health unit levels, providing regular reports during the vaccination campaign that display individual coverage rates and the proportion of administrations appropriately matched to age-specific recommendations, compared with regional and local benchmarks. These mechanisms could be integrated with broader access and delivery strategies, including the coordinated involvement of GPs, prevention departments, and community pharmacies.
The strengths of this study include the use of comprehensive, official data covering the entire regional population and a historical trend analysis capable of capturing long-term structural changes. However, some limitations must be acknowledged. The descriptive nature of the analysis lacks causal inference regarding the exact behavioral determinants behind provider-specific choices, and the recent integration of pharmacies means their long-term impact on overall coverage is still evolving. Moreover, the sub-protection estimates derived from the VE differential should be interpreted as conservative lower bounds, as they do not account for potential seasonal variations in influenza attack rates.
Conclusions
The integration of different provider, GPs, Pediatricians and community pharmacies, into Liguria’s seasonal influenza vaccination campaign represents a pivotal shift toward a more accessible, proximity-based healthcare model. However, our evaluation reveals that increased accessibility does not automatically translate to either optimal vaccination coverage or prescriptive appropriateness. While the multi-channel approach successfully redistributed the administration workload, coverage rates remain below national targets, and critical gaps persist in the use of enhanced vaccines for the vulnerable elderly population. Achieving true “precision vaccination” requires moving beyond structural expansion toward rigorous clinical governance, continuous professional training, and targeted public education – ensuring the right patient receives the right vaccine in any setting, and minimizing the clinical and socioeconomic burden of seasonal influenza.
Supplementary Material
Acknowledgments
Filippo Ansaldi, Giancarlo Icardi and Federico Grammatico: Conceptualization; Federico Grammatico, Daniela Amicizia, Irene Schenone, Andrea Orsi, Andrea Fiorano, Francesca Marchini, Matteo Astengo and Elvira Massaro: methodology; Matteo Astengo, Elvira Massaro, Andrea Fiorano, Francesca Marchini and Federico Grammatico: validation; Daniela Amicizia, Andrea Fiorano, Francesca Marchini, Matteo Astengo and Federico Grammatico: data curation; Daniela Amicizia and Irene Schenone: writing – original draft preparation; Daniela Amicizia, Irene Schenone and Elvira Massaro: writing – review and editing; Filippo Ansaldi, Giancarlo Icardi: visualization; Filippo Ansaldi, Giancarlo Icardi, Andrea Orsi: supervision. All authors have read and agreed to the published version of the manuscript.
Biographies
Daniela Amicizia is an Associate Professor of Hygiene and Preventive Medicine, University of Genoa Italy. Her research focuses on advancing vaccine strategies to prevent infectious disaeses, epidemiology and public health, health promotion, healthcare services planning and Health Technology Assessment (HTA).
Federico Grammatico is a physician affiliated with the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
Elvira Massaro is a Research of Hygiene and Preventive Medicine, University of Genoa Italy. Her research focuses on advancing vaccine strategies to prevent infectious disaeses, epidemiology, equity, public health and health promotion.
Irene Schenone is a physician affiliated with the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
Francesca Marchini is a physician affiliated with the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
Matteo Astengo is a physician affiliated with the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
Andrea Fiorano is a physician affiliated with the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
Andrea Orsi is an Associate Professor of Hygiene and Preventive Medicine, University of Genoa Italy. His research focuses on advancing vaccine strategies to prevent infectious disaeses, epidemiology, public health and health promotion.
Giancarlo Icardi is a Full Professor of Hygiene and Preventive Medicine, University of Genoa Italy. He is the director of Hygiene Unit, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy. His research focuses on advancing vaccine strategies to prevent infectious disaeses, epidemiology and public health.
Filippo Ansaldi is a Full Professor of Hygiene and Preventive Medicine, University of Genoa Italy. He is the director of the Department of Epidemiology, Prevention, and Health Data Analytics, IRCCS Azienda Ospedaliera Metropolitana (AOM), San Martino Policlinic Hospital, Genoa, Italy.
His research focuses on advancing vaccine strategies to prevent infectious disaeses, epidemiology, public health and healthcare services planning.
Funding Statement
The author(s) reported there is no funding associated with the work featured in this article.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
The data supporting the findings of this study are not publicly available because they comprise regional healthcare administrative data that are subject to institutional and regulatory restrictions. In accordance with the institutional responsibilities of A.Li.Sa. (Regional Law No. 17 of 29 July 2016), these data were processed for healthcare governance and research purposes.
De-identified data may be made available by the corresponding author upon reasonable request.
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/21645515.2026.2736958
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The data supporting the findings of this study are not publicly available because they comprise regional healthcare administrative data that are subject to institutional and regulatory restrictions. In accordance with the institutional responsibilities of A.Li.Sa. (Regional Law No. 17 of 29 July 2016), these data were processed for healthcare governance and research purposes.
De-identified data may be made available by the corresponding author upon reasonable request.