The Diasorin LIAISON SARS-CoV-2 Trimerics IgG (Diasorin, Saluggia, Italy) is a CLIA detecting IgG specific to the Trimeric Spike Glycoprotein. on anti-N serostatus, age, and sex in the very elderly adults. The data obtained could impact the organisation of the vaccination campaign (i.e., prioritisation strategies, administration of additional doses) and the factors that facilitate intentions to receive the vaccination among elderly adults (i.e., vaccine effectiveness). Subject terms: Geriatrics, Epidemiology Introduction Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was described in December 2019, with more than 412 million confirmed cases, including more than 5 million deaths, as of 15 February 20221. The mortality rate appears to be higher for elderly patients: 18.5% for patients between 70 and 79?years old and about 25% for patients older than 80?years. Conversely, it was ?90?years old is scarcely represented in the literature. To this aim, this study evaluates the antibody titres after the vaccination against SARS-CoV-2 in very elderly subjects (age?>?90?years old) and compares it to data obtained in a younger population (age 23C69?years old) in the context of a study conducted in Italy. The data obtained could impact the organisation of the vaccination campaign (i.e., prioritisation strategies, administration of additional doses) and the factors that facilitate intentions to receive the vaccination among elderly adults (i.e., vaccine effectiveness). Materials and methods Studied cohort and data sources This cross-sectional study used SARS-CoV-2 antibody test results from general (n. 1114 of 23C69?years old) and a very elderly population (n. 97 of 90C99?years old, named “+?90?years old population” in the manuscript) after the vaccination. The data gathered in the COVIDIAGNOSTIX project were collected from December 2020 HA15 to September 2021. According to the approved protocol (CE:199/INT/2020) of the Ethical Review Board of IRCCS San Raffaele Hospital, Mouse monoclonal to S1 Tag. S1 Tag is an epitope Tag composed of a nineresidue peptide, NANNPDWDF, derived from the hepatitis B virus preS1 region. Epitope Tags consisting of short sequences recognized by wellcharacterizated antibodies have been widely used in the study of protein expression in various systems. written informed consent was obtained from all the participants. The general population was composed of healthcare workers at IRCCS San Raffaele Hospital enrolled during the Italian COVID-19 vaccination campaign. The +?90?years old population includes subjects receiving home care assistance by the OSA Cooperative (Operatori Sanitari Associati ONLUS) for rehabilitation or medication purposes. The blood samples of the elderly adult population were collected by the HA15 staff of the OSA, participating as a partner in the COVIDIAGNOSTIX study. At the time of blood harvesting, the +?90 y/o cohort also underwent a rapid serological test. The blood samples were analysed at the Microbiology Laboratory of the Bambino Ges Childrens Hospital, involved in the study. Sampling was performed in both populations 6?months after the administration of the two doses required for the completion of the vaccination cycle. The vaccine administered was the BNT162b2 mRNA COVID-19 Vaccine; thus, the response depends exclusively on the recipient. Methods The antibody titre was tested in both study groups by the Elecsys Anti-SARS-CoV-2 assay (Roche, Basel, Switzerland) specific for the viral SARS-CoV-2 nucleocapsid (N) protein and by the Elecsys SARS-CoV-2-S (Roche, Basel, Switzerland) against the receptor-binding domain (RBD) of the viral spike protein (S-protein). The Roche Elecsys Anti-SARS-CoV-2 run on the COBAS 601.