Trends in influenza coverage rates in five consecutive immunisation seasons in the Local Health Unit of Ferrara (North Italy)

Seasonal influenza epidemics yearly affects 5-15% of the world's population, resulting in 3-5 million serious cases and up to 650,000 deaths. Elderly, pregnant women and individuals with underlying conditions are at increased risk of complications. According to the Italian National Immunisation Prevention Plan 2017-2019, these categories benefit from free vaccination but coverage rate in Italy are below desirable levels. The study considered the coverage rate in five consecutive influenza seasons (2010/2011-2014/2015) in Local Health Unit (LHU) of Ferrara (Italy). The amount of delivered vaccinations was not constant, with a decreasing trend. Coverage rose with increasing age, but the 75% target of over-65 years old individuals immunised was never achieved. In addition to age, coverage rates varied also according to District (the area of residence within the LHU). The District with the lowest vaccination coverage was the Western District. Higher levels of immunisation were observed in South-Eastern District in the pediatric age and in North-Central District in adult age group with a statistically significant difference. In the considered timespan, the percentage of immunisations delivered by the General Practitioners (GPs) increased. The trend in the LHU of Ferrara was similar to regional and national data, conditioned in the 2014/2015 season by the spreading of worrying news, although unfounded, on the safety of the vaccine. The GPs were essential in ensuring vaccine uptake, growing the percentage of delivered doses and achieving as much as possible effective elderly immunisation.