Keywords
Influenza vaccination
Excess mortality
Surveillance
Abstract
Introduction. Influenza remains a major public health concern, while vaccination coverage has persistently remained below national targets. This study aimed to describe influenza-related indicators in Piedmont over five influenza seasons and to compare regional findings with national data to inform current prevention strategies.
Methods. A descriptive analysis of the 2019/2020-2023/2024 influenza seasons was conducted using publicly available data from Piedmont and Italy. Weekly and cumulative Influenza-Like Illness (ILI) incidence were assessed overall and by age group. Virological surveillance data were used to describe circulating influenza strains, excess mortality among adults aged ≥65 years was estimated by comparing observed and expected weekly average daily deaths, and influenza vaccination coverage was analysed overall and by age group.
Results. Overall cumulative ILI incidence increased during the study period, despite a marked reduction in 2020/2021. Piedmont generally showed higher ILI incidence than Italy. Although children remained the most affected group, the gap between paediatric and adult/older age groups progressively narrowed, with a growing absolute burden among adults and older adults. Virological surveillance showed substantial variability across seasons, with influenza A predominating in most years. Excess mortality was highest in 2019/2020 and 2020/2021 and was generally more pronounced in Piedmont than nationally. Vaccination coverage improved compared with the pre-pandemic period but remained below national targets across key population groups.
Conclusion. Influenza-related burden in Piedmont remained considerable over the study period. These findings support the need for stronger vaccination strategies and integrated epidemiological, virological, and mortality surveillance to guide timely and context-specific public health action.
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