Clinical and Immunological Responses After SARS-CoV-2 Infection Causing COVID-19

There are very few long-term studies that analyze the immune responses in patients recovered from COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The main aim of this study is to analyze the clinical profile and immune responses of recovered COVID-19 patients in a representative cohort of people in the Umbria region of Italy. The participants had a history of testing positive for SARS-CoV-2 in March 2020 by Reverse Transcriptase- Quantitative Polymerase Chain Reaction (RT-qPCR). The participants were invited for voluntary participation in a seroprevalence study. This study analyzes longitudinally the presence of antibodies against SARS-CoV-2 by sequential serological tests at different time points using two FDA-approved Immunoassays. At the first serum sample collection, the participants were asked to provide information about their COVID-19 clinical history including clinical profile, co-morbidities, and treatment undertaken using a standardized questionnaire. Successive sequential serological assessments were conducted to understand the immune responses in these recovered patients. Moreover, stage two of the study involves, analysis of antibody titers in recovered vaccinated individuals and their follow-up.