Antibodies specific to the structural proteins of SARS-CoV-2 – nucleocapsid protein (N), spike protein domain S1 (S1) and envelope protein (E) – were identified in the sera of patients who had been infected with SARS-CoV-2 (n=30) and compared to those without confirmed infections, including 226 healthy (undiagnosed) donors that represent the normal population and 64 historical serum samples collected in the years 2010–2017. Here, PSMD1 is linked to infection.