ABSTRACT
Estimates of seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies have been hampered by inadequate assay sensitivity and specificity. Using an enzyme-linked immunosorbent assay-based approach that combines data about immunoglobulin G responses to both the nucleocapsid and spike receptor binding domain antigens, we show that excellent sensitivity and specificity can be achieved. We used this assay to assess the frequency of virus-specific antibodies in a cohort of elective surgery patients in Australia and estimated seroprevalence in Australia to be 0.28% (95% Confidence Interval, 0-1.15%). These data confirm the low level of transmission of SARS-CoV-2 in Australia before July 2020 and validate the specificity of our assay.
Subject(s)
Antibodies, Viral/analysis , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay , Seroepidemiologic Studies , Antigens, Viral/immunology , Australia , COVID-19/immunology , Coronavirus Nucleocapsid Proteins/immunology , Humans , Immunoglobulin G/analysis , Phosphoproteins/immunology , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/immunologyABSTRACT
Understanding which arms of the immune response are responsible for protection against SARS-CoV-2 infection is key to predicting long-term immunity and to inform vaccine design. Two studies in this issue of Cell collectively suggest that, although SARS-CoV-2 infection may blunt long-lived antibody responses, immune memory might still be achieved through virus-specific memory T cells.