Outpatient(1) serum samples(1) serum sample(1) COVID-19(1) collected(1) antibody(1) onset of symptoms(1) immunoassay(1) varicella(1) SARS-CoV-2-IgG(1) SARS-CoV-2 IgG(1) IgG response(1) S1/S2(1) Seven(1) S protein(1) evaluated(1) Antigen(1) laboratory diagnosis(1) Patient(1) IgG ELISA(1) Contact(1) ambulatory patients(1) FIVE(1) SARS-CoV-2(1) reported(1) Antibody Response(1) Elecsy(1) sensitivity(1) Zoster(1) novel(1)