ABSTRACT
Understanding the duration of antibodies to the SARS-CoV-2 virus that causes COVID-19 is important to controlling the current pandemic. Participants from the Texas Coronavirus Antibody REsponse Survey (Texas CARES) with at least one nucleocapsid protein antibody test were selected for a longitudinal analysis of antibody duration. A linear mixed model was fit to data from participants (n= 4,553) with one to three antibody tests over 11 months (10/1/2020-9/16/2021), and models fit showed that expected antibody response after COVID-19 infection robustly increases for 100 days post-infection, and predicts individuals may remain antibody positive from natural infection beyond 500 days, depending on age, body mass index, smoking or vaping use, and disease severity (hospitalized or not; symptomatic or not).