Background and Objective:
International literature suggests that disadvantaged groups are at higher risk of morbidity and mortality from SARS-CoV-2 infection due to poorer living/working conditions and barriers to healthcare access. In Lazio region (Italy), from June 2021, proximity health initiatives, such as mobile health unities (MHU), were put in place to ease the access to COVID-19 vaccinations, outside clinical settings (outreach), of irregular migrants, some of them without health coverage from Italian Health System (SSN).

Methods:
Data from 2021/2022 local Vaccination Centers of ASL Roma 6 and from the Regional Vaccination Registry (AVR) were integrated and analyzed. Demographic variables and those relating to administrative-welfare data were analyzed using descriptive methods.

Results:
272 irregular migrants were vaccinated from July 2021 to April 2022: 58,5% were male, average age was 34.6 years. 512 vaccine doses (primary series and booster doses) were administered. Most of them came from European area, in particular from Ukraine (30,1%). 77% has completed a primary series of vaccination and 53% of doses were provided by the MHU. All people found without health coverage during vaccination sessions (n.170, 62,5%) were regularized.

Conclusion:
In Italy, during the first year of campaign, SARS-CoV-2 vaccination avoided about 8 million infections, over 500,000 hospitalizations, over 55,000 ICU admissions and approximately 150,000 deaths, with a positive cost-effectiveness ratio. Through this local outreach initiative, a fragile population towards COVID-19 was able to benefit from the most effective form of primary prevention against the infection and administrative barriers to healthcare coverage have been removed. Migratory flowes and recent COVID-19 pandemic, challenge health systems to find and strengthen innovative approaches in health services offering.