The Georgia University Research Foundation to support the National Cancer Institute's multi-site study seeking to evaluate antibody responses to SARS-CoV-2 virus in high risk populations including health workers, first responders, frontline worker (e.g. grocery store employees) and disproportionately affected minorities. The goal of the study is to determine the durability of antibody titers following COVID infection and to identify correlates of antibody-mediated protection from re-infection in COVID survivors.