Local deprivation status and seasonal influenza vaccination coverage in adults ≥ 65 years residing in the Foggia municipality, Italy, 2009-2016

Introduction: In Italy, vaccination against seasonal influenza has been recommended for the elderly since 1980, but coverage is still far below the WHO minimum target level of 75%. Effective interventions to improve influenza vaccination should take into account socioeconomic determinants of inequalities in vaccine uptake. This study aimed to assess differences in vaccination coverage, by socioeconomic status, among people ≥ 65 years of age residing in the Foggia municipality, Italy. Methods: A Socio-Economic-Health Deprivation Index (SEHDI) was constructed by using a multivariate analysis model. The resident population, for census block, was classified in 5 deprivation groups. Differences in demographic and socioeconomic indicators, the standardized mortality ratios (SMRs), and the average vaccination coverage among deprivation groups were evaluated with the linear F-test. The association between census variables and influenza vaccination coverage, in each deprivation group, was assessed using the Pearson bivariate correlation. Results: The SEHDI allowed to identify factors related to ageing, housing, household size and composition, and education. Forty percent of people residing in the Foggia municipality lived in conditions of socioeconomic and health deprivation. Belonging to families with 3 or 4 members was associated with increased coverage rates. In the most deprived group, vaccination uptake was positively associated with the dependency ratio. Conclusions: The results of this study have shown that there is still large room for improving influenza vaccination coverage among subjects belonging to the most deprived areas. Surveillance of trends in influenza vaccine uptake by socioeconomic groups is a feasible contribution to implementing effective, tailored to the frail older persons, vaccine utilization programs.