A Persistent Positive Antibody Test in a Patient with No History of COVID-19 Infection

Antibody testing for SARS-CoV-2 has been established as a tool with broad utility in the surveillance and control of the COVID-19 pandemic. However, because of limited knowledge about the duration of humoral immunity to COVID-19 and the existence of unique individual immune responses, the potential role of antibody testing in the diagnosis of current and past infections of COVID-19 remains ambiguous. Herein, we describe a unique case of an asymptomatic patient showing a persistent positive total antibody test for SARS-CoV-2 while testing negative for SARS-CoV-2 RNA and IgG-specific antibodies. This case study shows how a combination of tests can be employed to identify a false positive and draw conclusions about a patient's COVID-19 status. It also highlights the complexity of using antibody testing for the diagnosis of COVID-19.