Background In occurrence of the coronavirus disease 19 (COVID-19) pandemic, carrying out an efficient large-scale vaccination campaign is vital in order to control the virus. Especially in high prevalence areas of COVID – 19, it is crucial to implement an effective vaccination strategy. In Italy, programming an efficient COVID-19 mass vaccination campaign has been the main target of the Ministry of Health. Aims This paper gives a comprehensive overview of how the mass vaccination campaign is performed in Milan, one of the cities that has been mostly affected by the COVID-19 pandemic in Italy. We analyze the vaccination strategy implemented by Fondazione Ca’ Granda – Ospedale Maggiore Policlinico located in Milan. Furthermore, we compare the organization of this campaign in regards of those carried out across EU and UK. Materials and Methods The data derive from an analysis of the different vaccination plans implemented across EU and UK from the 27/12/2020 to the 15/06/2020. In addition, we discuss the data collected from the internal data server of IRCCS Fondazione Ca’ Granda – Ospedale Maggiore Policlinico from the 15/02/2021 to the 15/06/2021.The collected data are examined by means of descriptive statistics. Results From the analysis of the internal data server, we observe that the modular organization of Fiera Milano City guarantees up to 5000 vaccinations/day. Moreover, the precise flow organization of users and a series of strategies adopted to avoid identification errors or vaccine type administration errors are crucial to reach the aforementioned target. Conclusions The institution of mass vaccination centers thanks to the optimization of all the involved processes and the meticulous organization of these structures, allows to avoid crowds and guarantees the administration of elevated amounts of vaccines. All these elements assure a rapid vaccination coverage of the population in Lombardy, with a meaningful increase in daily administration doses.

Background Since the start of the Sars-CoV-2 pandemic, attention was called on the potential risk of COVID-19 outbreaks occurring inside prisons. In detention facilities, timely and accurate diagnosis is essential for allowing case isolation and contact tracing to avoid the spread of the infection. Until recently, reverse-transcriptase polymerase chain reaction (rt-PCR) was the recommended method to diagnose SARS-CoV-2 infection. However, antigen-detecting rapid diagnostic tests (ag-RDT) have emerged as point-of-care testing techniques. Objectives Here, we evaluate the use of ag-RDT for screening of individuals newly admitted to San Vittore prison (SV), a pre-trial prison, in Milan (Lombardy region, Italy), during the second SARS-CoV2 epidemic peak. Methods During the period 1 October-31 December 2020, ag-RDT and rt-PCR were performed individuals newly admitted to SV. Results Among 504 detained individuals tested, 21 (4,2%) resulted positive to rt-PCR. Of these, 10 had tested negative with ag-RDT and 11 had concordant results. Rt-PCR cycle threshold (CT) values were above 35 for the individuals with ag-RDT negative test, therefore the cases missed by the ag-RDT are unlikely to transmit disease. For all the individuals with ag-RDT positive results, CT values were below or equal to 27. In our study population, ag-RDT sensitivity was 52.4% (29.8%-74.3%), positive predictive value (PPV) was 100% and negative predictive value was 98.0% (96.8%-98.7%). Discussion Our study showed that ag-RDT is a promising and useful component of serial testing strategies in prison settings to perform SARS-CoV2 screening at admission based to its high PPV, ease of use, lower costs and resource needs.