Effectiveness of on-site influenza vaccination strategy in Italian healthcare workers: a systematic review and statistical analysis

Introduction: One of the main determinants of non-adherence to influenza vaccination among healthcare workers (HCWs) is lack of time to attend vaccination services. Therefore, international Public Health Organizations have recommended on-site influenza vaccination in order to improve vaccination coverage among HCWs. Areas covered: We conducted a systematic narrative review of the relevant literature to evaluate the effectiveness of this strategy among HCWs in Italy. Fifteen studies, selected among scientific articles available in MEDLINE/PubMed, ISI Web of Knowledge and Scopus and published from January 1st, 2018, to May 31st, 2022, were included. A significant relationship was evidenced between influenza vaccine uptake and adoption of an on-site outpatient clinic (OR = 2.06; 95%CI = 1.43–2.95). The review highlighted a significant increase in VC when on-site vaccination was implemented (even exceeding +150% compared to the previous season), among other measures. Nevertheless, none of the reported experiences proved to meet the minimum target of 75% VC among HCWs. Expert opinion: Despite strategies to achieve greater willingness to immunize in this category, mandatory vaccination appears to be the only one that can guarantee protection for HCWs and the patients they care for.