Influenza and Covid-19 Vaccination in 2023: a descriptive analysis in two Italian Research and Teaching Hospitals. Is the On-Site strategy effective?

Introduction: Vaccinations represent an extremely effective tool for the prevention of certain infectious diseases - such as influenza and COVID-19 -, particularly for those categories at risk due to both their frail condition or professional exposure, such as healthcare workers. The aim of this study is to describe the course of the anti-influenza and anti-COVID-19 vaccination campaign at two Research Hospitals in Milan, Italy. Study design: Multicentre, cross-sectional study. Methods: For the 2023-24 vaccination campaign, the two facilities opted for two different approaches. At the Hospital A, two dif-ferent strategies for vaccinating healthcare workers were implemented: a fixed-site vaccination clinic and two mobile vaccination groups run by Public Health residents of the University of Milan. At the Hospital B, on the other hand, a single fixed-site outpatient clinic run by Public Health residents of the University of Milan was used. On the occasion of the campaign, a survey was also carried out using anonymous online questionnaires to investigate healthcare workers attitudes towards vaccination. Results: A total of 1,937 healthcare workers were vaccinated: 756 were immunized against influenza only, 99 against COVID-19 only, and 1,082 against both. The results show a substantial difference in vaccination adherence among medical and nursing staff compared to other professional categories. In particular, the category with the highest vaccination adhesion turned out to be that of medical doctors with 55.7% adhesion while, on the contrary, the category with the lowest adhesion turned out to be that of auxiliary personnel characterized by 7.4% adhesion. At the same time, the comparison between the two hospital facilities showed a double adherence rate by the staff of Hospital A as regards both the flu vaccine (40.6% and 20.1%) and the anti-COVID-19 vaccine (26.4% and 12.3%). Finally, the survey showed that the attitude towards influenza vaccination is lower among auxiliary staff in terms of both knowledge and vaccination attitude. Conclusions: The results of the study show a vaccination adherence in line with that of previous years, although lower than the values recommended by the principal national and international Organizations. The analysis of the differences between the two facilities and the surveys carried out will allow for the implementation of targeted interventions to increase adherence in future campaigns.

Side effects among healthcare workers from a large Milan university hospital after second dose of BNT162b2 mRNA COVID-19 vaccine.

BACKGROUND: In Italy, healthcare workers (HCWs) were among the first to receive COVID-19 vaccination. Aim of the present study is to evaluate frequency and severity of adverse events (AEs) following the second dose of BNT162b2 vaccine among HCWs of a large university hospital in Milan, Italy. METHODS: One month after having received the second dose of vaccine, HCWs filled-in a form about type, severity, and duration of post-vaccination local and systemic symptoms. We calculated the overall frequency of AEs and used multivariable Poisson regression models (adjusted for sex, age, BMI, smoking, allergy history, previous SARS-CoV-2 infection, anti-hypertensive therapy, and occupation) to calculate risk ratios (RR) and 95% confidence intervals (CI) of AEs according to selected variables. RESULTS: We included 3659 HCWs. Overall, 2801 (76.6%) experienced at least one local event, with pain at injection site being the most frequent (2788, 76.2%). Systemic events were reported by 2080 (56.8%) HCWs, with fatigue (52.3%), muscle pain (42.2%), headache (37.7%), joint pain (31.9%), and fever (26.2%) being the most frequent. Risks of systemic events were associated with female gender (RR=1.14, CI: 1.06-1.23), age (strong decrease with increasing age, p-trend<0.001), allergy history (RR=1.13, CI: 1.05-1.20), and current smoking (RR=0.90, CI: 0.84-0.97). HCWs with previous SARS-CoV-2 infection (even if symptomatic) were not at increased risk. CONCLUSIONS: Both local and systemic acute effects after second dose of BNT162b2 vaccine were frequently reported. However, symptoms were mostly light/mild and of short duration. Thus, our findings support the safety of COVID-19 vaccination in adults in relatively good health.

Vaccination Open Day: A Cross-Sectional Study on the 2023 Experience in Lombardy Region, Italy.

BACKGROUND: Vaccination is a highly effective tool for controlling infectious diseases, particularly in populations at high risk of contagion due to clinical conditions or occupational exposure, such as healthcare workers. The purpose of this study is to present the open day event that marked the beginning of the influenza and anti-COVID-19 vaccination campaign in the Lombardy region and to describe the experience of an Istituto di Ricovero e Cura a Carattere Scientifico in Milan. METHODS: During the vaccination open day, eligible individuals received free vaccinations for influenza, COVID-19, pneumococcal disease, and shingles, as provided by the Lombardy Agenzia per la Tutela della Salute. In celebration of the centenary of the Università degli Studi di Milano, the Fondazione Ca'Granda Ospedale Policlinico, a contracted hospital of the university, created a special electronic diary for a total of 150 individuals, equally divided between children aged 2-6, pregnant women, and university staff. RESULTS: At the regional level, a total of 6634 influenza vaccines, 2055 anti-COVID-19 vaccines, 108 anti-pneumococcal vaccines, and 37 anti-zoster vaccines were administered. A total of 3134 (47.3%) influenza vaccines, 1151 (56%) anti-COVID-19 vaccines, and 77 (62%) anti-pneumococcal vaccines, were given to individuals aged 60-79. No differences were observed between the total number of male and female vaccinees (1017 and 1038, respectively), who received the anti-COVID-19 vaccine. At the Policlinico Foundation, out of 150 available booking slots, 154 vaccines were administered, including 117 influenza vaccines. CONCLUSIONS: The establishment of vaccine open days is a beneficial way to increase vaccine compliance. Co-administration of little-known vaccinations outside of healthcare settings could also be a useful tool.

Medical occurrence and safety of SARS-CoV-2 vaccination outside of the hospital setting.

During COVID-19 pandemic, vaccination has been strongly recommended and advocated to prevent COVID-19 infection and adverse outcomes, particularly among at-risk populations. The vaccination against SARS-CoV-2 (COVAC) occurred at off-site locations capable of accommodating large crowds, distinct from the hospital setting, where a team of intensivists, emergency physicians, and nurses, ensuring prompt medical attention (medical occurrences, MO) in cases of adverse event following immunization. Our aims were to estimate the incidence of MO, and to assess its association with demographics, and vaccine characteristics. Our retrospective cohort study included all subject aged 12 years and older who received vaccinations at two large out-of-hospital vaccination hubs (Fiera Milano City, Palazzo delle Scintille), between April 12th and August 31st, 2021. Nine hundred and ninety-five thousand and twenty-eight vaccinations were administrated. MOs incidence rate was 278/100,000 doses (95% confidence interval (CI) 268-289). Most MOs were mild (86.27%) and mainly observed in subjects who received the Comirnaty vaccine; 92 MOs (3.32%) were severe and mostly occurred in recipients of the Vaxzeria vaccine. The incidence rate for hospital transfers following vaccination was 4.7/100,000 doses (95% CI 3.5-6.2) and any level of anaphylaxis occurred in 0.4 cases per 100,000 administrated doses (95% CI 0.3.-0.7). Sex, age, type of vaccine and first dose were associated with incidence of MO. Our results showed a low incidence rate in MOs after COVAC, mainly mild and support the feasibility, effectiveness and safety of vaccinations administered in hubs with a dedicated SEU located outside of the hospital setting.

Anti-Sars-CoV-2 vaccination campaign in children aged 5-11 years: the experience of a mass vaccination center in the city of Milan.

BACKGROUND AND AIM: After the approval of the anti-Sars-CoV-2 vaccines for the pediatric population, it is necessary to encourage the immunization of children aged 5-11 years, as this can reduce intergenerational transmission. Therefore, this goal has become a priority for the COVID 19 vaccination campaign in Italy. In the city of Milan, the mass vaccination center (MVC) Fiera Milano City, previously settled for general population, became the main site to host pediatric vaccinations. The center was consequently remodeled to ensure a suitable space for children. This paper provides an overview on the organization strategy implemented by Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico. The modular structure and the wide surface available in the center allowed the administration of hundreds of vaccines per day, especially in the first opening phase. METHODS: All the data for the entire period of activity of Fiera MCV, from December 16th 2021 to February 20th 2022, were analyzed using descriptive statistics. RESULTS: During the entire period of activity, from 16 December 2021 to 20 February 2022, 23% of the population in the province of Milan aged 5-11 years has been reached and vaccinated with at least one shot of vaccine in this center. CONCLUSIONS: Despite an enthusiastic response in the first weeks of the campaign, a progressive reduction in vaccination adherence was observed, maybe due to the absence of restrictive measures for unvaccinated children in Italy.

Setting up and managing the largest COVID-19 mass vaccination center in Lombardy, Italy.

Background: The rapid global spread of severe acute respiratory syndrome coronavirus (SARS-CoV-2) was met with the rollout of vaccination campaigns at mass vaccination centers. The Palazzo delle Scintille, Milan, was designated by the Lombardy regional administration as a vaccination site with the target of processing about 9,000 users daily. Methods: For this observational study, we compared data on vaccinations delivered at the Palazzo delle Scintille with coronavirus disease (COVID-19)-related regional data. Results: Between 25 April 2021 and 28 February 2023, a total of 1,885,822 COVID-19 doses were administered; the mean hourly rate was 289 (247.2), the mean daily rate was 3185.5 (3104.5), the mean user age was 49.5 years (10.7). The Comirnaty vaccine (Pfizer-BioNTech) was most often given (1,072,030/1,885,822; 56.8%). Between 4 December 2021 and 15 January 2022, the daily dose rate was above the maximum daily capacity set by the regional administration. Conclusion: The trend for daily dose rates administered at the Palazzo delle Scintille center was in line with COVID-19-related regional data. The center played a major role in the regional mass vaccination campaign.

Italy's rollout of COVID-19 vaccinations: The crucial contribution of the first experimental mass vaccination site in Lombardy.

BACKGROUND: In occurrence of the coronavirusdisease 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.