SARS-CoV-2 Serological Antibody Testing for Disease Surveillance and Clinical Use

Abstract Serologic testing for presence of SARS-CoV-2 antibodies is a critical tool for understanding the epidemiology and designing control strategies for the COVID-19 pandemic. Our understanding of the epidemiology of this pandemic is primarily derived from real-time data on the number of polymerase chain reaction (PCR)-positive

COVID-19 patients in outpatient and inpatient settings, and thus misses patients with asymptomatic infection or who have not had SARS-CoV-2 PCR testing. Serologic testing for SARS-CoV-2 antibodies can identify persons who have been exposed and infected with SARS-CoV-2 at any time and might be a correlate of

protective immunity. This project aims to advance our understanding of SARS-CoV-2 serological testing at the individual and population-level. To achieve this we will develop and implement a large-scale, population- based, flexible platform to assess SARS-CoV-2 sero-prevalence, sero-incidence, risk of sero-conversion and

longevity of antibody response in a large, integrated health system with linked rich demographic, behavioral and clinical data. For Aim 1 we will establish a community cohort of Kaiser Permanente Northern California (KPNC) members; a random sample of community dwelling persons, age 7-years and older, will be invited to

participate in ongoing surveillance of antibody development to assess population-level sero-prevalence and sero-incidence. For Aim 2, we will enroll a cohort of persons who are positive for SARS-CoV-2 PCR or antibodies and will follow them prospectively with repeat SARS-CoV-2 antibody testing for immune surveillance

and to determine longevity of antibody response. For Aim 3, we will establish a data-only cohort of all persons who have been diagnosed with COVID-19 disease, or had SARS-CoV-2 PCR or antibody testing; As of July 15, 2020, there are about 290,000 such persons in KPNC and the number increases daily as we test ~10,000

persons per day. In this cohort, we will assess risk of SARS-CoV-2 re-infection and will have the opportunity to examine interactions with a personal history of cancer or cancer treatment and other clinical factors or comorbid conditions, to determine if these conditions influence the likelihood of development of COVID-19 or

reinfection. For Aim 4, we will establish mechanisms for collaboration with other scientists in the Serological Sciences Network, including mechanisms for additional sample collection. This series of linked studies embedded in a large, integrated health system with a large number of COVID-19 patients and high SARS-

CoV-2 testing capacity will enhance our understanding of the utility of commercially available, large-scale SARS-CoV-2 antibody testing for population-level and individual-level disease control.